This page lists the objects exposed by the Google Visualization API, and the standard methods exposed by all visualizations.
Note: The Google Visualization API namespace is
google.visualization.*
A Note on Arrays
Some browsers don't properly handle trailing commas in JavaScript arrays, so don't use them. Empty values in the middle of an array are fine. So, for example:
data = ['a','b','c', ,]; // BAD
data = ['a','b','c']; // OK
data = ['a','b', ,'d']; // Also OK. The third value is undefined.
DataTable Class
Represents a two-dimensional, mutable table of values. To make a read-only copy of a
DataTable
(optionally filtered to show specific values, rows, or columns), create a
DataView.
Each column is assigned a data type, plus several optional properties including an ID, label, and pattern string.
In addition, you can assign custom properties (name/value pairs) to any cell, row, column, or the entire table. Some visualizations support specific custom properties; for example the Table visualization supports a cell property called 'style', which lets you assign an inline CSS style string to the rendered table cell. A visualization should describe in its documentation any custom properties that it supports.
See also: QueryResponse.getDataTable
Constructor
Syntax
DataTable(opt_data, opt_version)
- opt_data
-
[Optional] Data used to initialize the table. This can either be the JSON returned by
calling
DataTable.toJSON()
on a populated table, or a JavaScript object containing data used to initialize the table. The structure of the JavaScript literal object is described here. If this parameter is not supplied, a new, empty data table will be returned. - opt_version
- [Optional] A numeric value specifying the version of the wire protocol used. This is only used by Chart Tools Datasource implementors. The current version is 0.6.
Details
The DataTable
object is used to hold the data passed into a visualization.
A DataTable
is a basic two-dimensional table. All data in each column must have the
same data type. Each column has a descriptor that includes its data type, a label for that column
(which might be displayed by a visualization), and an ID, which can be used to refer to a specific
column (as an alternative to using column indexes). The DataTable
object also
supports a map of arbitrary properties assigned to a specific value, a row, a column, or the whole
DataTable
. Visualizations can use these to support additional features; for example,
the Table visualization uses
custom properties to let you assign arbitrary class names or styles to individual cells.
Each cell in the table holds a value. Cells can have a null value, or a value of the type specified by its column. Cells optionally can take a "formatted" version of the data; this is a string version of the data, formatted for display by a visualization. A visualization can (but is not required to) use the formatted version for display, but will always use the data itself for any sorting or calculations that it makes (such as determining where on a graph to place a point). An example might be assigning the values "low" "medium", and "high" as formatted values to numeric cell values of 1, 2, and 3.
To add data rows after calling the constructor, you can call either
addRow()
for a single row, or
addRows()
for multiple rows. You can add columns as
well by calling the addColumn()
methods. There are
removal methods for rows and columns as well, but rather than removing rows or columns, consider
creating a DataView
that is a selective view of the DataTable
.
If you change values in a DataTable
after it is passed into a visualization's
draw()
method, the changes will not immediately change the chart. You must call
draw()
again to reflect any changes.
Note: Google Charts does not perform any validation on datatables. (If it did, charts would be slower to render.) If you provide a number where your column is expecting a string, or vice versa, Google Charts will do its level best to interpret the value in a way that makes sense, but will not flag mistakes.
Examples
The following example demonstrates instantiating and populating a DataTable
with a
literal string, with the same data as shown in the JavaScript example above:
var dt = new google.visualization.DataTable({ cols: [{id: 'task', label: 'Task', type: 'string'}, {id: 'hours', label: 'Hours per Day', type: 'number'}], rows: [{c:[{v: 'Work'}, {v: 11}]}, {c:[{v: 'Eat'}, {v: 2}]}, {c:[{v: 'Commute'}, {v: 2}]}, {c:[{v: 'Watch TV'}, {v:2}]}, {c:[{v: 'Sleep'}, {v:7, f:'7.000'}]}] }, 0.6);
The following example creates a new, empty DataTable
and then populates it manually
with the same data as above:
var data = new google.visualization.DataTable(); data.addColumn('string', 'Task'); data.addColumn('number', 'Hours per Day'); data.addRows([ ['Work', 11], ['Eat', 2], ['Commute', 2], ['Watch TV', 2], ['Sleep', {v:7, f:'7.000'}] ]);
You can create a DataTable
either by calling the constructor without parameters and
then adding values by calling the addColumn()
/
addRows()
methods listed below, or by passing in
a populated JavaScript literal object to initialize it. Both methods are described below. Which
one should you use?
-
Creating and populating a table in JavaScript by calling
addColumn()
,addRow()
, andaddRows()
is very readable code. This method is useful when you'll be entering code by hand. It is slower than using object literal notation (described next), but in smaller tables (say, 1,000 cells) you probably won't notice much difference. -
Direct declaration of the
DataTable
object using object-literal notation is considerably faster in large tables. However, it can be a tricky syntax to get right; use this if you can generate the object literal syntax in code, which reduces possibility of errors.
Methods
Method | Return Value | Description |
---|---|---|
OR
|
Number |
Adds a new column to the data table, and returns the index of the new column. All the cells
of the new column are assigned a First signature has the following parameters:
Second signature has a single object parameter with the following members:
See also: getColumnId, getColumnLabel, getColumnType, insertColumn, getColumnRole |
addRow(opt_cellArray) |
Number |
Adds a new row to the data table, and returns the index of the new row.
Examples: data.addRow(); // Add an empty row data.addRow(['Hermione', new Date(1999,0,1)]); // Add a row with a string and a date value. // Add a row with two cells, the second with a formatted value. data.addRow(['Hermione', {v: new Date(1999,0,1), f: 'January First, Nineteen ninety-nine'} ]); data.addRow(['Col1Val', null, 'Col3Val']); // Second column is undefined. data.addRow(['Col1Val', , 'Col3Val']); // Same as previous. |
addRows(numOrArray) |
Number |
Adds new rows to the data table, and returns the index of the last added row. You can call this method to create new empty rows, or with data used to populate the rows, as described below.
Example: data.addRows([ ['Ivan', new Date(1977,2,28)], ['Igor', new Date(1962,7,5)], ['Felix', new Date(1983,11,17)], ['Bob', null] // No date set for Bob. ]); See also: insertRows |
clone() |
DataTable | Returns a clone of the data table. The result is a deep copy of the data table except for the cell properties, row properties, table properties and column properties, which are shallow copies; this means that non-primitive properties are copied by reference, but primitive properties are copied by value. |
getColumnId(columnIndex) |
String |
Returns the identifier of a given column specified by the column index in the underlying
table. For data tables that are retrieved by queries, the column identifier is set by the data source, and can be used to refer to columns when using the query language. See also: Query.setQuery |
getColumnIndex(columnIdentifier) |
String, Number |
Returns the index of a given column specified by the column index, id, or label if it exists
in this table, otherwise -1. When columnIdentifier is a string, it is used to
find the column by its id first, then by its label.See also: getColumnId, getColumnLabel |
getColumnLabel(columnIndex) |
String |
Returns the label of a given column specified by the column index in the underlying table.
The column label is typically displayed as part of the visualization. For example the column label can be displayed as a column header in a table, or as the legend label in a pie chart. For data tables that are retrieved by queries, the column label is set by the data source, or by the label clause of the
query language. See also: setColumnLabel |
getColumnPattern(columnIndex) |
String |
Returns the formatting pattern used to format the values of the specified column.
For data tables that are retrieved by queries, The column pattern is set by the data source,
or by the |
getColumnProperties(columnIndex)
|
Object |
Returns a map of all properties for the specified column. Note that the properties object is
returned by reference, so changing values in the retrieved object changes them in the
|
getColumnProperty(columnIndex, name)
|
Auto |
Returns the value of a named property, or
See also: setColumnProperty setColumnProperties |
getColumnRange(columnIndex) |
Object |
Returns the minimal and maximal values of values in a specified column. The returned object
has properties
|
getColumnRole(columnIndex) |
String | Returns the role of the specified column. |
getColumnType(columnIndex) |
String |
Returns the type of a given column specified by the column index.
The returned column type can be one of the following: |
getDistinctValues(columnIndex) |
Array of objects |
Returns the unique values in a certain column, in ascending order.
The type of the returned objects is the same as that returned by the
|
getFilteredRows(filters) |
Array of objects |
Returns the row indexes for rows that match all of the given filters. The indexes are
returned in ascending order. The output of this method can be used as input to
Another optional property,
Example: |
getFormattedValue(rowIndex, columnIndex)
|
String |
Returns the formatted value of the cell at the given row and column indexes.
For more on formatting column values see the query language reference. See also: setFormattedValue |
getNumberOfColumns() |
Number | Returns the number of columns in the table. |
getNumberOfRows() |
Number | Returns the number of rows in the table. |
getProperties(rowIndex, columnIndex)
|
Object |
Returns a map of all the properties for the specified cell. Note that the properties object
is returned by reference, so changing values in the retrieved object changes them in the
|
getProperty(rowIndex, columnIndex, name)
|
Auto |
Returns the value of a named property, or
See also: setCell setProperties setProperty |
getRowProperties(rowIndex)
|
Object |
Returns a map of all properties for the specified row. Note that the properties object is
returned by reference, so changing values in the retrieved object changes them in the
|
getRowProperty(rowIndex, name)
|
Auto |
Returns the value of a named property, or
See also: setRowProperty setRowProperties |
getSortedRows(sortColumns) |
Array of numbers |
Returns a sorted version of the table without modifying the order of the underlying data.
To permanently sort the underlying data, call
The returned value is an array of numbers, each number is an index of a
Note that the sorting is guaranteed to be stable: this means that if you sort on equal
values of two rows, the same sort will return the rows in the same order every time. Example: To iterate on rows ordered by the third column, use: var rowInds = data.getSortedRows([{column: 2}]); for (var i = 0; i < rowInds.length; i++) { var v = data.getValue(rowInds[i], 2); } |
getTableProperties
|
Object | Returns a map of all properties for the table. |
getTableProperty(name) |
Auto |
Returns the value of a named property, or
See also: setTableProperties setTableProperty |
getValue(rowIndex, columnIndex) |
Object |
Returns the value of the cell at the given row and column indexes.
The type of the returned value depends on the column type (see getColumnType):
|
insertColumn(columnIndex, type [,label [,id]])
|
None |
Inserts a new column to the data table, at the specifid index. All existing columns at or after the specified index are shifted to a higher index.
See also: addColumn |
insertRows(rowIndex, numberOrArray) |
None |
Insert the specified number of rows at the specified row index.
See also: addRows |
removeColumn(columnIndex) |
None |
Removes the column at the specified index.
See also: removeColumns |
removeColumns(columnIndex, numberOfColumns)
|
None |
Removes the specified number of columns starting from the column at the specified index.
See also: removeColumn |
removeRow(rowIndex) |
None |
Removes the row at the specified index.
See also: removeRows |
removeRows(rowIndex, numberOfRows) |
None |
Removes the specified number of rows starting from the row at the specified index.
See also: removeRow |
setCell(rowIndex, columnIndex [, value [, formattedValue [, properties]]])
|
None |
Sets the value, formatted value, and/or properties, of a cell.
See also: setValue(), setFormattedValue(), setProperty(), setProperties(). |
setColumnLabel(columnIndex, label)
|
None |
Sets the label of a column.
See also: getColumnLabel |
setColumnProperty(columnIndex, name, value)
|
None |
Sets a single column property. Some visualizations support row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also:setColumnProperties getColumnProperty |
setColumnProperties(columnIndex, properties)
|
None |
Sets multiple column properties. Some visualizations support row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setColumnProperty getColumnProperty |
setFormattedValue(rowIndex, columnIndex, formattedValue)
|
None |
Sets the formatted value of a cell.
See also: getFormattedValue |
setProperty(rowIndex, columnIndex, name, value)
|
None |
Sets a cell property. Some visualizations support row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setCell setProperties getProperty |
setProperties(rowIndex, columnIndex, properties)
|
None |
Sets multiple cell properties. Some visualizations support row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setCell setProperty getProperty |
setRowProperty(rowIndex, name, value)
|
None |
Sets a row property. Some visualizations support row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setRowProperties getRowProperty |
setRowProperties(rowIndex, properties)
|
None |
Sets multiple row properties. Some visualizations support row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setRowProperty getRowProperty |
setTableProperty(name, value)
|
None |
Sets a single table property. Some visualizations support table, row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setTableProperties getTableProperty |
setTableProperties(properties) |
None |
Sets multiple table properties. Some visualizations support table, row, column, or cell properties to modify their display or behavior; see the visualization documentation to see what properties are supported.
See also: setTableProperty getTableProperty |
setValue(rowIndex, columnIndex, value) |
None |
Sets the value of a cell. In addition to overwriting any existing cell value, this method will also clear out any formatted value and properties for the cell.
See also: setCell, setFormattedValue, setProperty, setProperties |
sort(sortColumns) |
None |
Sorts the rows, according to the specified sort columns. The DataTable is
modified by this method. See
getSortedRows() for a description of the
sorting details. This method does not return the sorted data.See also: getSortedRows Example: To sort by the third column and then by the second column, use: data.sort([{column: 2}, {column: 1}]);
|
toJSON() |
String |
Returns a JSON representation of the DataTable that can be passed into the
DataTable constructor. For
example:
{"cols":[{"id":"Col1","label":"","type":"date"}], "rows":[ {"c":[{"v":"a"},{"v":"Date(2010,10,6)"}]}, {"c":[{"v":"b"},{"v":"Date(2010,10,7)"}]} ] } |
Format of the Constructor's JavaScript Literal data Parameter
You can initialize a DataTable
by passing a JavaScript string literal object into
the data parameter. We'll call this object the data object. You can code this
object by hand, according to the description below, or you can use a
helper Python library if you know how to
use Python, and your site can use it. However, if you want to construct the object by hand, this
section will describe the syntax.
First, let's show an example of a simple JavaScript object describing a table with three rows and three columns (String, Number, and Date types):
{ cols: [{id: 'A', label: 'NEW A', type: 'string'}, {id: 'B', label: 'B-label', type: 'number'}, {id: 'C', label: 'C-label', type: 'date'} ], rows: [{c:[{v: 'a'}, {v: 1.0, f: 'One'}, {v: new Date(2008, 1, 28, 0, 31, 26), f: '2/28/08 12:31 AM'} ]}, {c:[{v: 'b'}, {v: 2.0, f: 'Two'}, {v: new Date(2008, 2, 30, 0, 31, 26), f: '3/30/08 12:31 AM'} ]}, {c:[{v: 'c'}, {v: 3.0, f: 'Three'}, {v: new Date(2008, 3, 30, 0, 31, 26), f: '4/30/08 12:31 AM'} ]} ], p: {foo: 'hello', bar: 'world!'} }
Now let's describe the syntax:
The data object consists of two required top-level properties, cols
and
rows
, and an optional p
property that is a map of arbitrary values.
Note: All property names and string constants shown are case-sensitive. Also,
properties described as taking a string value should have their value enclosed in quotation marks.
For example, if you wish to specify the type property as being number, it would be expressed like
this: type: 'number'
but the value itself, as numeric, would be expressed like this:
v: 42
cols
Property
cols
is an array of objects describing the ID and type of each column. Each property
is an object with the following properties (case-sensitive):
-
type
[Required] Data type of the data in the column. Supports the following string values (examples include the v: property, described later):-
'boolean' - JavaScript boolean value ('true' or 'false'). Example value:
v:'true'
-
'number' - JavaScript number value. Example values:
v:7
,v:3.14
,v:-55
- 'string' - JavaScript string value. Example value:
v:'hello'
-
'date' - JavaScript Date object (zero-based month), with the time truncated. Example
value:
v:new Date(2008, 0, 15)
-
'datetime' - JavaScript Date object including the time. Example value:
v:new Date(2008, 0, 15, 14, 30, 45)
-
'timeofday' - Array of three numbers and an optional fourth, representing hour
(0 indicates midnight), minute, second, and optional millisecond. Example values:
v:[8, 15, 0]
,v: [6, 12, 1, 144]
-
'boolean' - JavaScript boolean value ('true' or 'false'). Example value:
-
id
[Optional] String ID of the column. Must be unique in the table. Use basic alphanumeric characters, so the host page does not require fancy escapes to access the column in JavaScript. Be careful not to choose a JavaScript keyword. Example:id:'col_1'
-
label
[Optional] String value that some visualizations display for this column. Example:label:'Height'
-
pattern
[Optional] String pattern that was used by a data source to format numeric, date, or time column values. This is for reference only; you probably won't need to read the pattern, and it isn't required to exist. The Google Visualization client does not use this value (it reads the cell's formatted value). If theDataTable
has come from a data source in response to a query with a format clause, the pattern you specified in that clause will probably be returned in this value. The recommended pattern standards are the ICU DecimalFormat and SimpleDateFormat . -
p
[Optional] An object that is a map of custom values applied to the cell. These values can be of any JavaScript type. If your visualization supports any cell-level properties, it will describe them; otherwise, this property will be ignored. Example:p:{style: 'border: 1px solid green;'}
.
cols
Example
cols: [{id: 'A', label: 'NEW A', type: 'string'}, {id: 'B', label: 'B-label', type: 'number'}, {id: 'C', label: 'C-label', type: 'date'}]
The rows
property holds an array of row objects.
Each row object has one required property called c
, which is an array of cells in
that row. It also has an optional p
property that defines a map of arbitrary custom
values to assign to the whole row. If your visualization supports any row-level properties it will
describe them; otherwise, this property will be ignored.
Each cell in the table is described by an object with the following properties:
-
v
[Optional] The cell value. The data type should match the column data type. If the cell is null, thev
property should be null, though it can still havef
andp
properties. -
f
[Optional] A string version of thev
value, formatted for display. Typically the values will match, though they do not need to, so if you specifyDate(2008, 0, 1)
forv
, you should specify "January 1, 2008" or some such string for this property. This value is not checked against thev
value. The visualization will not use this value for calculation, only as a label for display. If omitted, a string version ofv
will be automatically generated using the default formatter. Thef
values can be modified using your own formatter, or set withsetFormattedValue()
orsetCell()
, or retrieved withgetFormattedValue()
. -
p
[Optional] An object that is a map of custom values applied to the cell. These values can be of any JavaScript type. If your visualization supports any cell-level properties, it will describe them. These properties can be retrieved by thegetProperty()
andgetProperties()
methods. Example:p:{style: 'border: 1px solid green;'}
.
Cells in the row array should be in the same order as their column descriptions in
cols
. To indicate a null cell, you can specify null
, leave a blank for a
cell in an array, or omit trailing array members. So, to indicate a row with null for the first
two cells, you could specify [ , , {cell_val}]
or
[null, null, {cell_val}]
.
Here is a sample table object with three columns, filled with three rows of data:
{ cols: [{id: 'A', label: 'NEW A', type: 'string'}, {id: 'B', label: 'B-label', type: 'number'}, {id: 'C', label: 'C-label', type: 'date'} ], rows: [{c:[{v: 'a'}, {v: 1.0, f: 'One'}, {v: new Date(2008, 1, 28, 0, 31, 26), f: '2/28/08 12:31 AM'} ]}, {c:[{v: 'b'}, {v: 2.0, f: 'Two'}, {v: new Date(2008, 2, 30, 0, 31, 26), f: '3/30/08 12:31 AM'} ]}, {c:[{v: 'c'}, {v: 3.0, f: 'Three'}, {v: new Date(2008, 3, 30, 0, 31, 26), f: '4/30/08 12:31 AM'} ]} ] }
p Property
The table-level p
property is a map of custom values applied to the whole
DataTable
. These values can be of any JavaScript type. If your visualization supports
any datatable-level properties, it will describe them; otherwise, this property will be available
for application use.
Example: p:{className: 'myDataTable'}
.
DataView Class
A read-only view of an underlying DataTable. A DataView
allows selection of only a subset of the columns and/or rows. It also allows reordering
columns/rows, and duplicating columns/rows.
A view is a live window on the underlying DataTable
, not a static snapshot of data.
However, you still must be careful when changing the structure of the table
itself, as described here:
-
Adding or removing columns from the underlying table will not be reflected by the view,
and might cause unexpected behavior in the view; you will have to create a new
DataView
from theDataTable
to pick up these changes. -
Adding or removing rows from the underlying table is safe and changes will be
propagated to the view immediately (but you must call
draw()
on any visualizations after this change to have the new row set rendered). Note that if your view has filtered out rows by calling one of thesetRows() or hideRows()
methods, and you add or remove rows from the underlying table, the behavior is unexpected; you must create a newDataView
to reflect the new table. -
Changing cell values in existing cells is safe, and changes are immediately propagated
to the
DataView
(but you must calldraw()
on any visualizations after this change to have the new cell values rendered).
It is also possible to create a DataView
from another DataView
. Note
that whenever an underlying table or view is mentioned, it refers to the level
immediately below this level. In other words, it refers to the data object used to construct this
DataView
.
DataView
also supports calculated columns; these are columns whose value is
calculated on the fly using a function that you supply. So, for example, you can include a column
that is a sum of two preceding columns, or a column that calculates and shows the calendar quarter
of a date from another column. See setColumns()
for more details.
When you modify a DataView
by hiding or showing rows or columns, the visualization
will not be affected until you call draw()
on the visualization again.
You can combine DataView.getFilteredRows()
with DataView.setRows()
to
create a DataView
with an interesting subset of data, as shown here:
var data = new google.visualization.DataTable(); data.addColumn('string', 'Employee Name'); data.addColumn('date', 'Start Date'); data.addRows(6); data.setCell(0, 0, 'Mike'); data.setCell(0, 1, new Date(2008, 1, 28)); data.setCell(1, 0, 'Bob'); data.setCell(1, 1, new Date(2007, 5, 1)); data.setCell(2, 0, 'Alice'); data.setCell(2, 1, new Date(2006, 7, 16)); data.setCell(3, 0, 'Frank'); data.setCell(3, 1, new Date(2007, 11, 28)); data.setCell(4, 0, 'Floyd'); data.setCell(4, 1, new Date(2005, 3, 13)); data.setCell(5, 0, 'Fritz'); data.setCell(5, 1, new Date(2007, 9, 2)); // Create a view that shows everyone hired since 2007. var view = new google.visualization.DataView(data); view.setRows(view.getFilteredRows([{column: 1, minValue: new Date(2007, 0, 1)}])); var table = new google.visualization.Table(document.getElementById('test_dataview')); table.draw(view, {sortColumn: 1});
Constructors
There are two ways to create a new DataView
instance:
Constructor 1
var myView = new google.visualization.DataView(data)
data
-
A
DataTable
orDataView
used to initialize the view. By default, the view contains all the columns and rows in the underlying data table or view, in the original order. To hide or show rows or columns in this view, call the appropriateset...()
orhide...()
methods.
See also:
setColumns(), hideColumns(), setRows(), hideRows().
Constructor 2
This constructor creates a new
DataView
by assigning a serialized DataView
to a DataTable
.
It helps you recreate the DataView
that you serialized using
DataView.toJSON()
.
var myView = google.visualization.DataView.fromJSON(data, viewAsJson)
- data
-
The
DataTable
object that you used to create theDataView
, on which you calledDataView.toJSON()
. If this table is any different from the original table, you will get unpredictable results. - viewAsJson
-
The JSON string returned by
DataView.toJSON()
. This is a description of which rows to show or hide from the data DataTable.
Methods
Method | Return Value | Description |
---|---|---|
See descriptions in DataTable . |
Same as the equivalent DataTable methods, except that row/column indexes refer to
the index in the view and not in the underlying table/view.
|
|
getTableColumnIndex(viewColumnIndex)
|
Number |
Returns the index in the underlying table (or view) of a given column specified by its index
in this view.
Example: If |
getTableRowIndex(viewRowIndex) |
Number |
Returns the index in the underlying table (or view) of a given row specified by its index in
this view.
Example: If |
getViewColumnIndex(tableColumnIndex)
|
Number |
Returns the index in this view that maps to a given column specified by its index in the
underlying table (or view). If more than one such index exists, returns the first (smallest)
one. If no such index exists (the specified column is not in the view), returns -1.
Example: If |
getViewColumns() |
Array of numbers |
Returns the columns in this view, in order. That is, if you call |
getViewRowIndex(tableRowIndex) |
Number |
Returns the index in this view that maps to a given row specified by its index in the
underlying table (or view). If more than one such index exists, returns the first (smallest)
one. If no such index exists (the specified row is not in the view), returns -1.
Example: If |
getViewRows() |
Array of numbers |
Returns the rows in this view, in order. That is, if you call |
hideColumns(columnIndexes) |
none |
Hides the specified columns from the current view.
Example: If you have a table with 10 columns, and you call
|
hideRows(min, max) |
None |
Hides all rows with indexes that lie between min and max (inclusive) from the current view.
This is a convenience syntax for |
hideRows(rowIndexes) |
None |
Hides the specified rows from the current view.
Example: If you have a table with 10 rows, and you call
|
setColumns(columnIndexes) |
None |
Specifies which columns are visible in this view. Any columns not specified will be hidden. This is an array of column indexes in the underlying table/view, or calculated columns. If you don't call this method, the default is to show all columns. The array can also contain duplicates, to show the same column multiple times. Columns will be shown in the order specified.
Examples: // Show some columns directly from the underlying data. // Shows column 3 twice. view.setColumns([3, 4, 3, 2]); // Underlying table has a column specifying a value in centimeters. // The view imports this directly, and creates a calculated column // that converts the value into inches. view.setColumns([1,{calc:cmToInches, type:'number', label:'Height in Inches'}]); function cmToInches(dataTable, rowNum){ return Math.floor(dataTable.getValue(rowNum, 1) / 2.54); } |
setRows(min, max) |
None |
Sets the rows in this view to be all indexes (in the underlying table/view) that lie between
min and max (inclusive). This is a convenience syntax for |
setRows(rowIndexes) |
None |
Sets the visible rows in this view, based on index numbers from the underlying table/view.
Example: To create a view with rows three and zero of an underlying
table/view: |
toDataTable() |
DataTable |
Returns a DataTable object populated with the visible rows and columns of the
DataView .
|
toJSON() |
string |
Returns a string representation of this DataView . Thisstring does not contain the
actual data; it only contains the DataView -specific settings such as visible rows
and columns. You can store this string and pass it to the static
DataView.fromJSON()
constructor to recreate this view. This won't include
generated columns.
|
ChartWrapper Class
A ChartWrapper
class is used to wrap your chart and handle all loading, drawing, and
Datasource querying for your chart. The class exposes convenience methods for setting values on
the chart and drawing it. This class simplifies reading from a data source, because you do not
have to create a query callback handler. You can also use it to save a chart easily for reuse.
Another bonus of using ChartWrapper
is that you can reduce the number of library
loads by using dynamic loading. Additionally, you don't need to load the packages explicitly
since ChartWrapper
will handle looking up and loading the chart packages for you.
See the examples below for details.
However, ChartWrapper
currently only propagates a subset of events thrown by charts:
select, ready, and error. Other events are not transmitted through the ChartWrapper instance; to
get other events, you must call getChart()
and subscribe to events directly on the
chart handle, as shown here:
var wrapper; function drawVisualization() { // Draw a column chart wrapper = new google.visualization.ChartWrapper({ chartType: 'ColumnChart', dataTable: [['Germany', 'USA', 'Brazil', 'Canada', 'France', 'RU'], [700, 300, 400, 500, 600, 800]], options: {'title': 'Countries'}, containerId: 'visualization' }); // Never called. google.visualization.events.addListener(wrapper, 'onmouseover', uselessHandler); // Must wait for the ready event in order to // request the chart and subscribe to 'onmouseover'. google.visualization.events.addListener(wrapper, 'ready', onReady); wrapper.draw(); // Never called function uselessHandler() { alert("I am never called!"); } function onReady() { google.visualization.events.addListener(wrapper.getChart(), 'onmouseover', usefulHandler); } // Called function usefulHandler() { alert("Mouseover event!"); } }
Constructor
ChartWrapper(opt_spec)
- opt_spec
- [Optional] - Either a JSON object defining the chart, or a serialized string version of that object. The format of this object is shown in the drawChart() documentation. If not specified, you must set all the appropriate properties using the set... methods exposed by this object.
Methods
ChartWrapper exposes the following additional methods:
Method | Return Type | Description |
---|---|---|
draw(opt_container_ref) |
None |
Draws the chart. You must call this method after any changes that you make to the chart or data to show the changes.
|
toJSON() |
String | Returns a string version of the JSON representation of the chart. |
clone() |
ChartWrapper | Returns a deep copy of the chart wrapper. |
getDataSourceUrl() |
String | If this chart gets its data from a data source, returns the URL for this data source. Otherwise, returns null. |
getDataTable() |
google.visualization.DataTable |
If this chart gets its data from a locally-defined
Any changes that you make to the returned object will be reflected by the chart the next
time you call |
getChartType() |
String |
The class name of the wrapped chart. If this is a Google chart, the name will not be qualified
with google.visualization . So, for example, if this were a Treemap chart,
it would return "Treemap" rather than "google.visualization.treemap".
|
getChartName() |
String | Returns the chart name assigned by setChartName() . |
getChart() |
Chart object reference |
Returns a reference to the chart created by this ChartWrapper, for example a
google.visualization.BarChart
or a
google.visualization.ColumnChart
.
This will return null until after you have called draw() on the ChartWrapper
object, and it throws a ready event. Methods called on the returned object will be reflected
on the page.
|
getContainerId() |
String | The ID of the chart's DOM container element. |
getQuery() |
String | The query string for this chart, if it has one and queries a data source. |
getRefreshInterval() |
Number | Any refresh interval for this chart, if it queries a data source. Zero indicates no refresh. |
getOption(key, opt_default_val) |
Any type |
Returns the specified chart option value
|
getOptions() |
Object | Returns the options object for this chart. |
getView() |
Object OR Array |
Returns the DataView initializer object, in the same format as
dataview.toJSON() , or an array of such objects.
|
setDataSourceUrl(url) |
None | Sets the URL of a data source to use for this chart. If you also set a data table for this object, the data source URL will be ignored. |
setDataTable(table) |
None | Sets the DataTable for the chart. Pass in one of the following: null; a DataTable object; a JSON representation of a DataTable; or an array following the syntax of arrayToDataTable(). |
setChartType(type) |
None |
Sets the chart type. Pass in the class name of the wrapped chart. If this is a Google chart,
do not qualify it with google.visualization . So, for example, for a pie chart,
pass in "PieChart".
|
setChartName(name) |
None | Sets an arbitrary name for the chart. This is not shown anywhere on the chart, unless a custom chart is explicitly designed to use it. |
setContainerId(id) |
None | Sets the ID of the containing DOM element for the chart. |
setQuery(query_string) |
None | Sets a query string, if this chart queries a data source. You must also set the data source URL if specifying this value. |
setRefreshInterval(interval) |
None | Sets the refresh interval for this chart, if it queries a data source. You must also set a data source URL if specifying this value. Zero indicates no refresh. |
setOption(key, value) |
None |
Sets a single chart option value, where key is the option name and value is
the value. To unset an option, pass in null for the value. Note that key may be a
qualified name, such as 'vAxis.title' .
|
setOptions(options_obj) |
None | Sets a complete options object for a chart. |
setView(view_spec) |
None |
Sets a DataView initializer object, which acts as a filter over the underlying
data. The chart wrapper must have underlying data from a DataTable or a data source to apply
this view to. You can pass in either a string or DataView initializer object,
like that returned by dataview.toJSON() . You can
also pass in an array of DataView initializer objects, in which case the first
DataView in the array is applied to the underlying data to create a new data
table, and the second DataView is applied to the data table resulting from
application of the first DataView , and so on.
|
Events
The ChartWrapper object throws the following events. Note that you must call
ChartWrapper.draw()
before any events will be thrown.
Name | Description | Properties |
---|---|---|
error |
Fired when an error occurs when attempting to render the chart. | id, message |
ready |
The chart is ready for external method calls. If you want to interact with the chart, and call
methods after you draw it, you should set up a listener for this event before you call
the draw method, and call them only after the event was fired.
|
None |
select |
Fired when the user clicks a bar or legend. When a chart element is selected, the
corresponding cell in the data table is selected; when a legend is selected, the corresponding
column in the data table is selected. To learn what has been selected, call
ChartWrapper.getChart().
getSelection() . Note that this will only be thrown
when the underlying chart type throws a selection event.
|
None |
Example
The following two snippets create an equivalent line chart. The first example uses JSON literal notation to define the chart; the second uses ChartWrapper methods to set these values.
<!DOCTYPE html> <html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"/> <title>Google Visualization API Sample</title> <!-- One script tag loads all the required libraries! --> <script type="text/javascript" src='https://www.gstatic.com/charts/loader.js'></script> <script> google.charts.load('current); google.charts.setOnLoadCallback(drawVisualization); function drawVisualization() { var wrap = new google.visualization.ChartWrapper({ 'chartType':'LineChart', 'dataSourceUrl':'http://spreadsheets.google.com/tq?key=pCQbetd-CptGXxxQIG7VFIQ&pub=1', 'containerId':'visualization', 'query':'SELECT A,D WHERE D > 100 ORDER BY D', 'options': {'title':'Population Density (people/km^2)', 'legend':'none'} }); wrap.draw(); } </script> </head> <body> <div id="visualization" style="height: 400px; width: 400px;"></div> </body> </html>
Same chart, now using setter methods:
<!DOCTYPE html> <html> <head> <meta http-equiv='content-type' content='text/html; charset=utf-8'/> <title>Google Visualization API Sample</title> <!-- One script tag loads all the required libraries! --> <script type="text/javascript" src='https://www.gstatic.com/charts/loader.js'></script> <script type="text/javascript"> google.charts.load('current'); google.charts.setOnLoadCallback(drawVisualization); function drawVisualization() { // Define the chart using setters: var wrap = new google.visualization.ChartWrapper(); wrap.setChartType('LineChart'); wrap.setDataSourceUrl('http://spreadsheets.google.com/tq?key=pCQbetd-CptGXxxQIG7VFIQ&pub=1'); wrap.setContainerId('visualization'); wrap.setQuery('SELECT A,D WHERE D > 100 ORDER BY D'); wrap.setOptions({'title':'Population Density (people/km^2)', 'legend':'none'}); wrap.draw(); } </script> </head> <body> <div id='visualization' style='height: 400px; width: 400px;'></div> </body> </html>
ChartEditor Class
The ChartEditor
class is used to open an in-page dialog box that enables a user to
customize a visualization on the fly.
To use ChartEditor:
-
Load the
charteditor
package. Ingoogle.charts.load()
, load the package 'charteditor'. You do not need to load the packages for the chart type that you render in the editor; the chart editor will load any package for you as needed. -
Create a
ChartWrapper
object that defines the chart for the user to customize. This chart will be shown in the dialog, and the user uses the editor to redesign the chart, change chart types, or even change the source data. -
Create a new ChartEditor instance, and register to listen for the "ok"
event. This event is thrown when the user clicks the "OK" button on the
dialog. When received, you should call
ChartEditor.getChartWrapper()
to retrieve the user-modified chart. -
Call
ChartEditor.openDialog()
, passing in theChartWrapper
. This opens the dialog. The dialog buttons enable the user to close the editor. TheChartEditor
instance is available as long as it is in scope; it is not automatically destroyed after the user closes the dialog. - To update the chart in code, call
setChartWrapper()
.
Methods
Method | Return Value | Description |
---|---|---|
openDialog(chartWrapper, opt_options) |
null |
Opens the chart editor as an embedded dialog box on the page. The function returns
immediately; it does not wait for the dialog to be closed. If you do not lose scope of the
instance, you can call
|
getChartWrapper() |
ChartWrapper |
Returns a ChartWrapper representing the chart, with user modifications. |
setChartWrapper(chartWrapper) |
null |
Use this method to update the rendered chart on the editor.
chartWrapper - A |
closeDialog() |
null | Closes the chart editor dialog box. |
Options
The chart editor supports the following options:
Name | Type | Default | Description |
---|---|---|---|
dataSourceInput |
Element handle or 'urlbox' | null |
Use this to enable the user to specify a data source for the chart. This property can be one of two values:
|
Events
The chart editor throws the following events:
Name | Description | Properties |
---|---|---|
ok |
Fired when the user clicks the "OK" button on the dialog. After receiving this
method, you should call getChartWrapper() to retrieve the user-configured chart.
|
none |
cancel |
Fired when the user clicks the "Cancel" button on the dialog. | none |
Example
The following example code opens a chart editor dialog with a populated line chart. If the user
clicks "OK", the edited chart will be saved to the specified <div>
on the page.
<!DOCTYPE html> <html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"/> <title> Google Visualization API Sample </title> <script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script> <script type="text/javascript"> google.charts.load('current', {packages: ['charteditor']}); </script> <script type="text/javascript"> google.charts.setOnLoadCallback(loadEditor); var chartEditor = null; function loadEditor() { // Create the chart to edit. var wrapper = new google.visualization.ChartWrapper({ 'chartType':'LineChart', 'dataSourceUrl':'http://spreadsheets.google.com/tq?key=pCQbetd-CptGXxxQIG7VFIQ&pub=1', 'query':'SELECT A,D WHERE D > 100 ORDER BY D', 'options': {'title':'Population Density (people/km^2)', 'legend':'none'} }); chartEditor = new google.visualization.ChartEditor(); google.visualization.events.addListener(chartEditor, 'ok', redrawChart); chartEditor.openDialog(wrapper, {}); } // On "OK" save the chart to a <div> on the page. function redrawChart(){ chartEditor.getChartWrapper().draw(document.getElementById('vis_div')); } </script> </head> <body> <div id="vis_div" style="height: 400px; width: 600px;"></div> </body> </html>
Data Manipulation Methods
The google.visualization.data
namespace holds static methods to perform SQL-like
operations on DataTable
objects, for example joining them or grouping by column
value.
The google.visualization.data
namespace exposes the following methods:
Method | Description |
---|---|
google.visualization.data.group
|
Performs a SQL GROUP BY action to return a table grouped by values in specified columns. |
google.visualization.data.join
|
Joins two data tables on one or more key columns. |
group()
Takes a populated DataTable
object and performs a SQL-like GROUP BY operation,
returning a table with rows grouped by the specified column values. Note that this does not modify
the input DataTable
.
The returned table includes one row for each combination of values in the specified key columns. Each row includes the key columns, plus one column with an aggregated column value over all rows that match the key combination (for example, a sum or count of all values in the specified column).
The google.visualization.data
namespace includes several useful aggregation values
(for example, sum and
count), but you can define your own (for example,
standardDeviation or secondHighest). Instructions on how to define your own aggregator are given
after the method description.
Syntax
google.visualization.data.group(data_table, keys, columns)
- data_table
-
The input
DataTable
. This will not be modified by callinggroup()
. - keys
-
An array of numbers and/or objects specifying which columns to group by. The result table
includes every column in this array, as well as every column in columns. If a number,
this is a column index of the input
DataTable
to group by. If an object, it will include a function that can modify the specified column (for example, add 1 to the value in that column). The object must have the following properties:- column - A number that is a column index from dt to apply the transformation to.
- modifier - A function that accepts one value (the cell value in that column for each row), and returns the modified value. This function is used to modify the column value to assist in the grouping: for example, by calling a whichQuarter function that calculates a quarter from a date column, so the API can group rows by quarter. The calculated value is displayed in the key columns in the returned table. This function can be declared inline inside this object, or it can be a function that you define elsewhere in your code (it must be within the calling scope). The API provides one simple modifier function; here are instructions on how to create your own, more useful functions. You must know the data type that this function can accept, and call it only on columns of that type. You must also know the return type of this function, and declare it in the type property described next.
- type - The type returned by the function modifier. This should be a JavaScript string type name, for example: 'number' or 'boolean'.
-
label - [Optional] A string label to assign this column in the
returned
DataTable
. -
id - [Optional] A string ID to assign this column in the returned
DataTable
.
Examples:[0]
,[0,2]
,[0,{column:1, modifier:myPlusOneFunc, type:'number'},2]
- columns
-
[Optional] Lets you specify which columns, in addition to key columns, to include in
the output table. Because all rows in the row group are compressed into a single output row,
you must determine what value to display for that row group. For example, you could choose to
show the column value from the first row in the set, or an average of all rows in that group.
columns is an array of objects, with the following properties:
- column - A number specifying the index of the column to show.
- aggregation - A function that accepts an array of all values of this column in this row group and returns a single value to display in the result row. The return value must be of the type specified by the object's type property. Details on creating your own aggregation function are given below. You must know what data types this method accepts and only call it on columns of the appropriate type. The API provides several useful aggregation functions. See Provided Aggregation Functions below for a list, or Creating an aggregation function to learn how to write your own aggregation function.
- type - The return type of the aggregation function. This should be a JavaScript string type name, for example: 'number' or 'boolean'.
- label - [Optional] A string label to apply to this column in the returned table.
- id - [Optional] A string ID to apply to this column in the returned table.
Return Value
A DataTable
with one column for each column listed in keys and one column
for each column listed in columns. The table is sorted by key rows, from left to right.
Example
// This call will group the table by column 0 values. // It will also show column 3, which will be a sum of // values in that column for that row group. var result = google.visualization.data.group( dt, [0], [{'column': 3, 'aggregation': google.visualization.data.sum, 'type': 'number'}] ); *Input table* 1 'john' 'doe' 10 1 'jane' 'doe' 100 3 'jill' 'jones' 50 3 'jack' 'jones' 75 5 'al' 'weisenheimer' 500 *Output table* 1 110 3 125 5 500
Provided Modifier Functions
The API provides the following modifier functions that you can pass into the keys. modifier parameter to customize grouping behavior.
Function | Input Array Type | Return Type | Description |
---|---|---|---|
google.visualization.data.month |
Date | number | Given a date, it will return the zero-based month value (0, 1, 2, and so on). |
Provided Aggregation Functions
The API provides the following aggregation functions that you can pass into the columns. aggregation parameter array.
Function | Input Array Type | Return Type | Description |
---|---|---|---|
google.visualization.data.avg |
number | number | The average value of the array passed in. |
google.visualization.data.count |
any type | number | The count of rows in the group. Null and duplicate values are counted. |
google.visualization.data.max |
number, string, Date | number, string, Date, null | The maximum value in the array. For strings, this is the first item in an lexicographically sorted list; for Date values, it is the latest date. Nulls are ignored. Returns null if there is no maximum. |
google.visualization.data.min |
number, string, Date | number, string, Date, null | The minimum value in the array. For strings, this is the last item in an lexicographically sorted list; for Date values, it is the earliest date. Nulls are ignored. Returns null if if there is no minimum. |
google.visualization.data.sum |
number | number | The sum of all values in the array. |
Creating a modifier function
You can create a modifier function to perform a simple transformation onkey values before the
group()
function groups your rows. This function takes a single cell value, performs
an action on it (for example, adds 1 to the value), and returns it. The input and return types
need not be the same type, but the caller must know the input and output types. Here's an example
of a function that accepts a date and returns the quarter:
// Input type: Date // Return type: number (1-4) function getQuarter(someDate) { return Math.floor(someDate.getMonth()/3) + 1; }
Creating an aggregation function
You can create an aggregation function that accepts a set of column values in a row group and returns a single number: for example, returning a count or average of values. Here is an implementation of the provided count aggregation function, which returns a count of how many rows are in the row group:
// Input type: Array of any type // Return type: number function count(values) { return values.length; }
join()
This method joins two data tables (DataTable
or DataView
objects) into a
single results table, similar to a SQL JOIN statement. You specify one or more column pairs
(key columns) between the two tables, and the output table includes the rows according to
a join method that you specify: only rows where both keys match; all rows from one table; or all
rows from both tables, whether or not the keys match. The results table includes only the key
columns, plus any additional columns that you specify. Note that dt2 cannot have
duplicate keys, but dt1 can. The term "key" means the combination of all key
column values, not a specific key column value; so if a row has cell values A | B | C and columns
0 and 1 are key columns, then the key for that row is AB.
Syntax
google.visualization.data.join(dt1, dt2, joinMethod, keys, dt1Columns, dt2Columns);
- dt1
- A populated
DataTable
to join with dt2. - dt2
-
A populated
DataTable
to join with dt1. This table cannot have multiple identical keys (where a key is a combination of key column values). - joinMethod
-
A string specifying the join type. If dt1 has multiple rows that match a dt2
row, the output table will include all matching dt1 rows. Choose from the following
values:
- 'full' - The output table includes all rows from both tables, regardless of whether keys match. Unmatched rows will have null cell entries; matched rows are joined.
- 'inner' - The full join filtered to include only rows where the keys match.
- 'left' - The output table includes all rows from dt1, whether or not there are any matching rows from dt2.
- 'right' - The output table includes all rows from dt2, whether or not there are any matching rows from dt1.
- keys
-
An array of key columns to compare from both tables. Each pair is a two element array, the first
is a key in dt1, the second is a key in dt2. This array can specify columns
by their index, id, or label, see
getColumnIndex
.
Columns must be the same type in both tables. All specified keys must match according to the rule given by joinMethod in order to include a row from the table. Key columns are always included in the output table. Only dt1, the left-hand table, can include duplicate keys; keys in dt2 must be unique. The term "key" here means a unique set of key columns, not individual column values. For example, if your key columns were A and B, the following table would have only unique key values (and could thus be used as dt2):A B Jen Red Jen Blue Fred Red [[0,0], [2,1]]
compares values from the first column in both tables as well as the third column from dt1 with the second column from dt2. - dt1Columns
-
An array of columns from dt1 to include in the output table, in addition to
dt1's key columns. This array can specify columns by their index, id, or label, see
getColumnIndex
. - dt2Columns
-
An array of columns from dt2 to include in the output table, in addition to
dt2's key columns. This array can specify columns by their index, id, or label, see
getColumnIndex
.
Return Value
A DataTable
with the key columns, dt1Columns, and dt2Columns. This
table is sorted by the key columns, from left to right. When joinMethod is 'inner', all
key cells should be populated. For other join methods, if no matching key is found, the table will
have a null for any unmatched key cells.
Examples
*Tables* dt1 dt2 bob | 111 | red bob | 111 | point bob | 111 | green ellyn | 222 | square bob | 333 | orange jane | 555 | circle fred | 555 | blue jane | 777 | triangle jane | 777 | yellow fred | 666 | dodecahedron * Note that right table has duplicate Jane entries, but the key we will use is * columns 0 and 1. The left table has duplicate key values, but that is * allowed. *Inner join* google.visualization.data.join(dt1, dt2, 'inner', [[0,0],[1,1]], [2], [2]); bob | 111 | red | point bob | 111 | green | point jane | 777 | yellow | triangle * Note that both rows from dt1 are included and matched to * the equivalent dt2 row. *Full join* google.visualization.data.join(dt1, dt2, 'full', [[0,0],[1,1]], [2], [2]); bob | 111 | red | point bob | 111 | green | point bob | 333 | orange | null ellyn | 222 | null | square fred | 555 | blue | null fred | 666 | null | dodecahedron jane | 555 | null | circle jane | 777 | yellow | triangle *Left join* google.visualization.data.join(dt1, dt2, 'left', [[0,0],[1,1]], [2], [2]); bob | 111 | red | point bob | 111 | green | point bob | 333 | orange | null fred | 555 | blue | null jane | 777 | yellow | triangle *Right join* google.visualization.data.join(dt1, dt2, 'right', [[0,0],[1,1]], [2], [2]); bob | 111 | red | point bob | 111 | green | point ellyn | 222 | null | square fred | 666 | null | dodecahedron jane | 555 | null | circle jane | 777 | yellow | triangle
Formatters
The Google Visualization API provides formatters that can be used to reformat data in a visualization. These formatters change the formatted value of the specified column in all rows. Note that:
- Formatters modify only the formatted values, not the underlying values. For example, the displayed value would be "$1,000.00" but the underlying value would still be "1000".
- Formatters only affect one column at a time; to reformat multiple columns, apply a formatter to each column that you want to change.
- If you also use user-defined formatters, certain Google Visualization formatters will override all user-defined formatters.
- Get your populated
DataTable
object. - For each column that you want to reformat:
- Create an object that specifies all the options for your formatter. This is a basic JavaScript object with a set of properties and values. Look at your formatter's documentation to see what properties are supported. (Optionally, you can pass in an object literal notation object specifying your options.)
- Create your formatter, passing in your options object.
-
Call
formatter
.format(table, colIndex)
, passing in theDataTable
and the (zero-based) column number of the data to reformat. Note that you can only apply a single formatter to each column; applying a second formatter will simply overwrite the effects of the first.
Important: Many formatters require HTML tags to display special formatting; if your visualization supports anallowHtml
option, you should set it to true.
- options - A generic JavaScript object that specifies the options for that formatter. This object is a generic object with property/value pairs with properties specific to that formatter. See the documentationfor your specific formatter to learn what options are supported. Here are two example ways to call the constructor for the DateFormat object, passing in two properties:
-
data - A
DataTable
containing the data to reformat. You cannot use a DataView here. - colIndex - The zero-based index of the column to format. To format multiple columns, you must call this method multiple times, with different colIndex values.
- from - [String, Number, Date, DateTime, or TimeOfDay] The lower boundary (inclusive) of the range, or null. If null, it will match -∞. String boundaries are compared alphabetically against string values.
- to - [String, Number, Date, DateTime, or TimeOfDay] The high boundary (non-inclusive) of the range, or null. If null, it will match +∞. String boundaries are compared alphabetically against string values.
- color - The color to apply to text in matching cells. Values can be either '#RRGGBB' values or defined color constants, (example: '#FF0000' or 'red').
- bgcolor - The color to apply to the background of matching cells. Values can be either '#RRGGBB' values or defined color constants, (example: '#FF0000' or 'red').
- from - [Number, Date, DateTime, or TimeOfDay] The lower boundary (inclusive) of the range, or null. If null, it will match -∞.
- to - [Number, Date, DateTime, or TimeOfDay] The higher boundary (non-inclusive) of the range, or null. If null, it will match +∞.
- color - The color to apply to text in matching cells. This color is the same for all cells, no matter what their value.
- fromBgColor - The background color for cells holding values at the low end of the gradient. Values can be either '#RRGGBB' values or defined color constants, (example: '#FF0000' or 'red').
- toBgColor - The background color for cells holding values at the high end of the gradient. Values can be either '#RRGGBB' values or defined color constants, (example: '#FF0000' or 'red').
- 'short' - Short format: e.g., "2/28/16"
- 'medium' - Medium format: e.g., "Feb 28, 2016"
- 'long' - Long format: e.g., "February 28, 2016"
- M produces 1
- MM produces 01
- MMM produces Jan
- MMMM produces January
- E produces T
- EE or EEE Produce Tu or Tues
- EEEE Produces Tuesday
- dataTable - The DataTable on which to operate.
- srcColumnIndices - An array of one or more (zero-based) column indices to pull as the sources from the underlying DataTable. This will be used as a data source for the pattern parameter in the constructor. The column numbers do not have to be in sorted order.
- opt_dstColumnIndex - [optional] The destination column to place the output of the pattern manipulation. If not specified, the first element in srcColumIndices will be used as the destination.
- Preference
_table_query_url
is used to set the Query data source URL. -
Preference
_table_query_refresh_interval
is used to set the Query refresh interval (in seconds). - Query - Wraps the outgoing data request.
- QueryResponse - Handles the response from the data source.
- dataSourceUrl
- [Required, String] URL to send the query to. See the Charts and Spreadsheets documentation for Google Spreadsheets.
- opt_options
-
[Optional, Object] A map of options for the request. Note: If you are
accessing a
restricted data source
,
you should not use this parameter. Here are the supported properties:
-
sendMethod - [Optional, String] Specifies the method to use to
send the query. Choose one of the following string values:
- 'xhr' - Send the query using XmlHttpRequest.
- 'scriptInjection' - Send the query using script injection.
-
'makeRequest' - [Available only for gadgets, which are
deprecated] Send the query using the Gadget API
makeRequest()
method. If specified, you should also specify makeRequestParams. -
'auto' - Use the method specified by the
tqrt
URL parameter from the data source URL.tqrt
can have the following values: 'xhr', 'scriptInjection', or 'makeRequest'. Iftqrt
is missing or has an invalid value, the default is 'xhr' for same-domain requests and 'scriptInjection' for cross-domain requests.
-
makeRequestParams - [Object] A map of parameters for a
makeRequest()
query. Used and required only if sendMethod is 'makeRequest'.
-
sendMethod - [Optional, String] Specifies the method to use to
send the query. Choose one of the following string values:
-
access_denied
The user does not have permissions to access the data source. invalid_query
The specified query has a syntax error.-
data_truncated
One or more data rows that match the query selection were not returned due to output size limits. (warning). timeout
The query did not respond within the expected time.- container - The DOM element into which to insert the error message. If the container cannot be found, the function will throw a JavaScript error.
- message - A string message to display.
- opt_detailedMessage - An optional detailed message string. By default, this is mouseover text, but that can be changed in the opt_options.showInToolTip property described below.
-
opt_options - An optional object with properties that set various display options
for the message. The following options are supported:
- showInTooltip - A boolean value where true shows the detailed message only as tooltip text, and false shows the detailed message in the container body after the short message. Default value is true.
- type - A string describing the error type, which determines which css styles should be applied to this message. The supported values are 'error' and 'warning'. Default value is 'error'.
-
style - A style string for the error message. This style will
override any styles applied to the warning type (opt_options.type). Example:
'background-color: #33ff99; padding: 2px;'
Default value is an empty string. - removable - A boolean value, where true means that the message can be closed by a mouse click from the user. Default value is false.
- container - The DOM element into which to insert the error message. If the container cannot be found, the function will throw a JavaScript error.
- response - A QueryResponse object received by your query handler in response to a query. If this is null, the method will throw a JavaScript error.
-
id - The string ID of an error created using
addError()
oraddErrorFromQueryResponse()
. - container - The DOM element holding the error strings to remove. If the container cannot be found, the function will throw a JavaScript error.
-
errorId - String ID of an error created using
addError()
oraddErrorFromQueryResponse()
. - google.visualization.events.addListener() and google.visualization.events.addOneTimeListener() listen for events.
- google.visualization.events.removeListener() removes an existing listener
- google.visualization.events.removeAllListeners() removes all listeners of a specific chart
- google.visualization.events.trigger() fires an event.
- source_visualization
- A handle to the source visualization instance.
- event_name
- The string name of the event to listen for. A visualization should document which events it throws.
- handling_function
- The name of the local JavaScript function to call when source_visualization fires the event_name event. The handling function will be passed any event arguments as parameters.
- listener_handler
- The listener handler to remove, as returned by google.visualization.events.addListener().
- source_visualization
- A handle to the source visualization instance from which all event listeners should be removed.
- source_visualization
-
A handle to the source visualization instance. If you are calling this function from within a
method defined by the sending visualization, you can simply pass in the
this
keyword. - event_name
- A string name to call the event. You can choose any string value that you want.
- event_args
- [optional] A map of name/value pairs to pass to the receiving method. For example: {message: "Hello there!", score: 10, name: "Fred"}. You can pass null if no events are needed; the receiver should be prepared to accept null for this parameter.
- Constructor
- draw()
- getAction() [optional]
- getSelection() [optional]
- removeAction() [optional]
- setAction() [optional]
- setSelection() [optional]
- dom_element
- A pointer to a DOM element where the visualization should be embedded.
- data
-
A
DataTable
orDataView
holding the data to use to draw the chart. There is no standard method for extracting aDataTable
from a chart. - options
-
[Optional] A map of name/value pairs of custom options. Examples include height and
width, background colors, and captions. The visualization documentation should list which
options are available, and should support default options if you do not specify this parameter.
You can use the JavaScript object literal syntax to pass in an options map: e.g.,
{x:100, y:200, title:'An Example'}
- selection_array
-
An array of objects, each with a numeric row and/or column property.
row
andcolumn
are the zero-based row or column number of an item in the data table to select. To select a whole column, setrow
to null; to select a whole row, setcolumn
to null. Example:setSelection([{row:0,column:1},{row:1, column:null}])
selects the cell at (0,1) and the entire row 1. - twoDArray
- A two-dimensional array, where each row represents a row in the data table. If opt_firstRowIsData is false (the default), the first row will be interpreted as header labels. The data types of each column are interpreted automatically from the data given. If a cell has no value, specify a null or empty value as appropriate.
- opt_firstRowIsData
- Whether the first row defines a header row or not. If true, all rows are assumed to be data. If false, the first row is assumed to be a header row, and the values are assigned as column labels. Default is false.
- chart_JSON_or_object
- Either a JSON literal string or a JavaScript object, with the following properties (case-sensitive):
The actual formatting applied to the data is derived from the locale the API has been loaded with. For more details, see loading charts with a specific locale .
Important: Formatters can only be used with a DataTable
; they cannot
be used with a DataView
(DataView
objects are read-only).
Here are the general steps for using a formatter:
Here is an example of changing the formatted date values of a date column to use a long date format ("January 1, 2009"):
var data = new google.visualization.DataTable(); data.addColumn('string', 'Employee Name'); data.addColumn('date', 'Start Date'); data.addRows(3); data.setCell(0, 0, 'Mike'); data.setCell(0, 1, new Date(2008, 1, 28)); data.setCell(1, 0, 'Bob'); data.setCell(1, 1, new Date(2007, 5, 1)); data.setCell(2, 0, 'Alice'); data.setCell(2, 1, new Date(2006, 7, 16)); // Create a formatter. // This example uses object literal notation to define the options. var formatter = new google.visualization.DateFormat({formatType: 'long'}); // Reformat our data. formatter.format(data, 1); // Draw our data var table = new google.visualization.Table(document.getElementById('dateformat_div')); table.draw(data, {showRowNumber: true});
Most formatters expose the following two methods:
Method | Description |
---|---|
google.visualization.formatter_name(options) |
Constructor, where formatter_name is a specfic formatterclass name. // Object literal technique var formatter = new google.visualization.DateFormat({formatType: 'long', timeZone: -5}); // Equivalent property setting technique var options = new Object(); options['formatType'] = 'long'; options['timeZone'] = -5; var formatter = new google.visualization.DateFormat(options); |
format(data, colIndex) |
Reformats the data in the specified column. |
The Google Visualization API provides the following formatters:
Formatter Name | Description |
---|---|
ArrowFormat | Adds an up or down arrow, indicating whether the cell value is above or below a specified value. |
BarFormat | Adds a colored bar, the direction and color of which indicates whether the cell value is above or below a specified value. |
ColorFormat | Colors a cell according to whether the values fall within a specified range. |
DateFormat | Formats a Date or DateTime value in several different ways, including "January 1, 2009," "1/1/09" and "Jan 1, 2009." |
NumberFormat | Formats various aspects of numeric values. |
PatternFormat | Concatenates cell values on the same row into a specified cell, along with arbitrary text. |
ArrowFormat
Adds an up or down arrow to a numeric cell, depending on whether the value is above or below a specified base value. If equal to the base value, no arrow is shown.
Options
ArrowFormat
supports the following options, passed in to the constructor:
Option | Description |
---|---|
base |
A number indicating the base value, used to compare against the cell value. If the cell value is higher, the cell will include a green up arrow; if the cell value is lower, it will include a red down arrow; if the same, no arrow. |
Sample code
var data = new google.visualization.DataTable(); data.addColumn('string', 'Department'); data.addColumn('number', 'Revenues Change'); data.addRows([ ['Shoes', {v:12, f:'12.0%'}], ['Sports', {v:-7.3, f:'-7.3%'}], ['Toys', {v:0, f:'0%'}], ['Electronics', {v:-2.1, f:'-2.1%'}], ['Food', {v:22, f:'22.0%'}] ]); var table = new google.visualization.Table(document.getElementById('arrowformat_div')); var formatter = new google.visualization.ArrowFormat(); formatter.format(data, 1); // Apply formatter to second column table.draw(data, {allowHtml: true, showRowNumber: true});
BarFormat
Adds a colored bar to a numeric cell indicating whether the cell value is above or below a specified base value.
Options
BarFormat
supports the following options, passed in to the constructor:
Option | ExampleDescription |
---|---|
base |
A number that is the base value to compare the cell value against. If the cell value is higher, it will be drawn to the right of the base; if lower, it will be drawn to the left. Default value is 0. |
colorNegative |
A string indicating the negative value section of bars. Possible values are 'red', 'green' and 'blue'; default value is 'red'. |
colorPositive |
A string indicating the color of the positive value section of bars. Possible values are 'red', 'green' and 'blue'. Default is 'blue'. |
drawZeroLine |
A boolean indicating if to draw a 1 pixel dark base line when negative values are present. The dark line is there to enhance visual scanning of the bars. Default value is 'false'. |
max |
The maximum number value for the bar range. Default value is the highest value in the table. |
min |
The minimum number value for the bar range. Default value is the lowest value in the table. |
showValue |
If true, shows values and bars; if false, shows only bars. Default value is true. |
width |
Thickness of each bar, in pixels. Default value is 100. |
Sample code
var data = new google.visualization.DataTable(); data.addColumn('string', 'Department'); data.addColumn('number', 'Revenues'); data.addRows([ ['Shoes', 10700], ['Sports', -15400], ['Toys', 12500], ['Electronics', -2100], ['Food', 22600], ['Art', 1100] ]); var table = new google.visualization.Table(document.getElementById('barformat_div')); var formatter = new google.visualization.BarFormat({width: 120}); formatter.format(data, 1); // Apply formatter to second column table.draw(data, {allowHtml: true, showRowNumber: true, width: '100%', height: '100%'});
ColorFormat
Assigns colors to the foreground or background of a numeric cell,
depending on the cell value. This formatter is an unusual, in that
it doesn't take its options in the constructor. Instead, you should
call addRange()
or addGradientRange()
as
many times as you want, to add color ranges, before
calling format()
. Colors can be specified in any
acceptable HTML format, for example "black",
"#000000", or "#000".
Methods
ColorFormat
supports the following methods:
Method | Description |
---|---|
google.visualization.ColorFormat() |
Constructor. Takes no arguments. |
addRange(from, to, color, bgcolor) |
Specifies a foreground color and/or background color to a cell, depending on the cell value. Any cell with a value in the specified from—to range will be assigned color and bgcolor. It is important to realize that the range is non-inclusive, because creating a range from 1—1,000 and a second from 1,000— 2,000 will not cover the value 1,000! |
addGradientRange(from, to, color, fromBgColor,
toBgColor)
|
Assigns a background color from a range, according to the cell value. The color is scaled to
match the cell's value within a range from a lower boundary color to an upper boundary
color. Note that this method cannot compare string values, as
|
format(dataTable, columnIndex) |
The standard format() method to apply formatting to the specified column. |
Sample code
var data = new google.visualization.DataTable(); data.addColumn('string', 'Department'); data.addColumn('number', 'Revenues'); data.addRows([ ['Shoes', 10700], ['Sports', -15400], ['Toys', 12500], ['Electronics', -2100], ['Food', 22600], ['Art', 1100] ]); var table = new google.visualization.Table(document.getElementById('colorformat_div')); var formatter = new google.visualization.ColorFormat(); formatter.addRange(-20000, 0, 'white', 'orange'); formatter.addRange(20000, null, 'red', '#33ff33'); formatter.format(data, 1); // Apply formatter to second column table.draw(data, {allowHtml: true, showRowNumber: true, width: '100%', height: '100%'});
DateFormat
Formats a JavaScript Date
value in a variety of ways, including "January 1,
2016," "1/1/16" and "Jan 1, 2016".
Options
DateFormat
supports the following options, passed in to the constructor:
Option | Description |
---|---|
formatType |
A quick formatting option for the date. The following string values are supported, reformatting the date February 28, 2016 as shown: You cannot specify both |
pattern |
A custom format pattern to apply to the value, similar to the
ICU date and time format.
For example:
You cannot specify both |
timeZone |
The time zone in which to display the date value. This is a numeric value, indicating GMT +
this number of time zones (can be negative). Date object are created by default with the
assumed time zone of the computer on which they are created; this option is used to display
that value in a different time zone. For example, if you created a Date object of 5pm noon on
a computer located in Greenwich, England, and specified timeZone to be -5
(options['timeZone'] = -5 , or Eastern Pacific Time in the US), the value
displayed would be 12 noon.
|
Methods
DateFormat
supports the following methods:
Method | Description |
---|---|
google.visualization.DateFormat(options) |
Constructor. See the options section above for more info. |
format(dataTable, columnIndex) |
The standard format() method to apply formatting to the
specified column. |
formatValue(value) |
Returns the formatted value of a given value.
This method does not require a |
Sample code
function drawDateFormatTable() { var data = new google.visualization.DataTable(); data.addColumn('string', 'Employee Name'); data.addColumn('date', 'Start Date (Long)'); data.addColumn('date', 'Start Date (Medium)'); data.addColumn('date', 'Start Date (Short)'); data.addRows([ ['Mike', new Date(2008, 1, 28, 0, 31, 26), new Date(2008, 1, 28, 0, 31, 26), new Date(2008, 1, 28, 0, 31, 26)], ['Bob', new Date(2007, 5, 1, 0), new Date(2007, 5, 1, 0), new Date(2007, 5, 1, 0)], ['Alice', new Date(2006, 7, 16), new Date(2006, 7, 16), new Date(2006, 7, 16)] ]); // Create three formatters in three styles. var formatter_long = new google.visualization.DateFormat({formatType: 'long'}); var formatter_medium = new google.visualization.DateFormat({formatType: 'medium'}); var formatter_short = new google.visualization.DateFormat({formatType: 'short'}); // Reformat our data. formatter_long.format(data, 1); formatter_medium.format(data,2); formatter_short.format(data, 3); // Draw our data var table = new google.visualization.Table(document.getElementById('dateformat_div')); table.draw(data, {showRowNumber: true, width: '100%', height: '100%'}); }
More About Date Patterns
Here are some more details on what patterns are supported:
The patterns are similar to the ICU
date and time format, but the following patterns are not yet supported: A e D F g Y u w W. To
avoid collision with patterns, any literal text you want to appear in the output should be
surrounded by single quotes, except for the single quote, which should be doubled: e.g.,
"K 'o''clock.'"
.
Pattern | Description | Example Output |
---|---|---|
GG | Era designator. | "AD" |
yy or yyyy | year. | 1996 |
M |
Month in year. For January: |
"July" "07" |
d | Day in month. Extra 'd' values will add leading zeros. | 10 |
h | Hour in 12 hour scale. Extra 'h' values will add leading zeros. | 12 |
H | Hour in 24 hour scale. Extra Hk' values will add leading zeros. | 0 |
m | Minute in hour. Extra 'M' values will add leading zeros. | 30 |
s | Second in minute. Extra 's' values will add leading zeros. | 55 |
S | Fractional second. Extra 'S' values will be padded on the right with zeros. | 978 |
E |
Day of week. Following outputs for "Tuesday": |
"Tues" "Tuesday" |
aa | AM/PM | "PM" |
k | Hour in day (1~24). Extra 'k' values will add leading zeros. | 24 |
K | Hour in AM/PM (0~11). Extra 'k' values will add leading zeros. | 0 |
z | Time zone. For time zone 5, produces "UTC+5" |
"UTC+5" |
Z |
Time zone in RFC 822 format. For time zone -5: Z, ZZ, ZZZ produce -0500 ZZZZ and more produce "GMT -05:00" |
"-0800" "GMT -05:00" |
v | Time zone (generic). |
"Etc/GMT-5" |
' | escape for text | 'Date=' |
'' | single quote | ''yy |
NumberFormat
Describes how numeric columns should be formatted. Formatting options include specifying a prefix symbol (such as a dollar sign) or the punctuation to use as a thousands marker.
Options
NumberFormat
supports the following options, passed in to the constructor:
Option | Description |
---|---|
decimalSymbol |
A character to use as the decimal marker. The default is a dot (.). |
fractionDigits |
A number specifying how many digits to display after the decimal. The default is 2. If you specify more digits than the number contains, it will display zeros for the smaller values. Truncated values will be rounded (5 rounded up). |
groupingSymbol |
A character to be used to group digits to the left of the decimal into sets of three. Default is a comma (,). |
negativeColor |
The text color for negative values. No default value. Values can be any acceptable HTML color value, such as "red" or "#FF0000". |
negativeParens |
A boolean, where true indicates that negative values should be surrounded by parentheses. Default is true. |
pattern |
A format string. When provided, all other options are ignored, except
The format string is a subset of the
ICU pattern set
.
For instance, |
prefix |
A string prefix for the value, for example "$". |
suffix |
A string suffix for the value, for example "%". |
Methods
NumberFormat
supports the following methods:
Method | Description |
---|---|
google.visualization.NumberFormat(options) |
Constructor. See the options section above for more info. |
format(dataTable, columnIndex) |
The standard format() method to apply formatting to the specified column. |
formatValue(value) |
Returns the formatted value of a given value. This method does not require a
|
Sample code
var data = new google.visualization.DataTable(); data.addColumn('string', 'Department'); data.addColumn('number', 'Revenues'); data.addRows([ ['Shoes', 10700], ['Sports', -15400], ['Toys', 12500], ['Electronics', -2100], ['Food', 22600], ['Art', 1100] ]); var table = new google.visualization.Table(document.getElementById('numberformat_div')); var formatter = new google.visualization.NumberFormat( {prefix: '$', negativeColor: 'red', negativeParens: true}); formatter.format(data, 1); // Apply formatter to second column table.draw(data, {allowHtml: true, showRowNumber: true, width: '100%', height: '100%'});
PatternFormat
Enables you to merge the values of designated columns into a single
column, along with arbitrary text. So, for example, if you had a
column for first name and a column for last name, you could populate
a third column with {last name}, {first name}. This formatter does
not follow the conventions for the constructor and
the format()
method. See the Methods section below for
instructions.
Methods
PatternFormat
supports the following methods:
Method | Description |
---|---|
google.visualization.PatternFormat(pattern) |
Constructor. Does not take an options object. Instead, it takes a string pattern
parameter. This is a string that describes which column values to put into the destination
column, along with any arbitrary text. Embed placeholders in your string to indicate a value
from another column to embed. The placeholders are
Sample codeThe following example demonstrates a constructor for a pattern
that creates an anchor element, with the first and second elements taken from the
var formatter = new google.visualization.PatternFormat( '<a href="mailto:{1}">{0}</a>'); |
format(dataTable, srcColumnIndices,
opt_dstColumnIndex)
|
The standard formatting call, with a few additional parameters: See the formatting examples after the table. |
Here are a few example inputs and outputs for a four-column table.
Row before formatting (4 columns, last is blank): John | Paul | Jones | [empty] var formatter = new google.visualization.PatternFormat("{0} {1} {2}"); formatter.format(data, [0,1,2], 3); Output: John | Paul | Jones | John Paul Jones var formatter = new google.visualization.PatternFormat("{1}, {0}"); formatter.format(data, [0,2], 3); Output: John | Paul | Jones | Jones, John
Sample code
The following example demonstrates how to combine data from two columns to create an email address. It uses a DataView object to hide the original source columns:
var data = new google.visualization.DataTable(); data.addColumn('string', 'Name'); data.addColumn('string', 'Email'); data.addRows([ ['John Lennon', '[email protected]'], ['Paul McCartney', '[email protected]'], ['George Harrison', '[email protected]'], ['Ringo Starr', '[email protected]'] ]); var table = new google.visualization.Table(document.getElementById('patternformat_div')); var formatter = new google.visualization.PatternFormat( '<a href="mailto:{1}">{0}</a>'); // Apply formatter and set the formatted value of the first column. formatter.format(data, [0, 1]); var view = new google.visualization.DataView(data); view.setColumns([0]); // Create a view with the first column only. table.draw(view, {allowHtml: true, showRowNumber: true, width: '100%', height: '100%'});
GadgetHelper
A helper class to simplify writing Gadgets that use the Google Visualization API.
Constructor
google.visualization.GadgetHelper()
Methods
Method | Return Value | Description |
---|---|---|
createQueryFromPrefs(prefs) |
google.visualization.Query |
Static. Create a new instance of google.visualization.Query and set its
properties according to values from the gadget preferences. The type of parameter
prefs is _IG_Prefs
|
validateResponse(response) |
Boolean |
Static. Parameter response is of type
google.visualization.QueryResponse. Returns true if
the response contains data. Returns false if the query execution failed and the
response does not contain data. If an error occurred, this method displays an error message.
|
Query Classes
The following objects are available to send queries for data to an external data source, such as Google Spreadsheets.
Query
Represents a query that is sent to a data source.
Constructor
google.visualization.Query(dataSourceUrl, opt_options)
Parameters
Methods
Method | Return Value | Description |
---|---|---|
abort() |
None |
Stops the automated query sending that was started with setRefreshInterval() .
|
setRefreshInterval(seconds)
|
None |
Sets the query to automatically call the If you use this method, you should call it before calling the
Cancel this method either by calling it again with zero (the default), or by calling
|
setTimeout(seconds) |
None |
Sets the number of seconds to wait for the data source to respond before raising a timeout
error. seconds is a number greater than zero. The default timeout is 30 seconds. This method, if used, should be called before calling the send method.
|
setQuery(string) |
None |
Sets the query string. The value of the string parameter should be a valid
query. This method, if used, should be called before calling the send method.
Learn more about the Query language.
|
send(callback) |
None |
Sends the query to the data source. callback should be a function that will be
called when the data source responds. The callback function will receive a single parameter of
type google.visualization.QueryResponse.
|
QueryResponse
Represents a response of a query execution as received from the data source. An instance of this class is passed as an argument to the callback function that was set when Query.send was called.
Methods
Method | Return Value | Description |
---|---|---|
getDataTable() |
DataTable |
Returns the data table as returned by the data source. Returns null if the query
execution failed and no data was returned.
|
getDetailedMessage() |
String | Returns a detailed error message for queries that failed. If the query execution was successful, this method returns an empty string. The message returned is a message that is intended for developers, and may contain technical information, for example 'Column {salary} does not exist'. |
getMessage() |
String | Returns a short error message for queries that failed. If the query execution was successful, this method returns an empty string. The message returned is a short message that is intended for end users, for example 'Invalid Query' or 'Access Denied'. |
getReasons() |
Array of strings |
Returns an array of zero of more entries. Each entry is a short string with an error or
warning code that was raised while executing the query. Possible codes:
|
hasWarning() |
Boolean | Returns true if the query execution has any warning messages. |
isError() |
Boolean |
Returns true if the query execution failed, and the response does not contain
any data table. Returns <false> if the query execution was successful and the response
contains a data table.
|
Error Display
The API provides several functions to help you display custom error messages to your users. To
use these functions, provide a container element on the page (typically a
<div>
), into which the API will draw a formatted error message. This container
can be either the visualization container element, or a container just for errors. If you specify
the visualization containe element, the error message will be displayed above the visualization.
Then call the appropriate function below to show, or remove, the error message.
All functions are static functions in the namespace google.visualization.errors
.
Many visualizations can throw an error event; see error event below to learn more about that.
You can see an example custom error in the Query Wrapper Example.
Function | Return Value | Description |
---|---|---|
addError(container, message, opt_detailedMessage,
opt_options)
|
String ID value that identifies the error object created. This is a unique value on the page, and can be used to remove the error or find its containing element. |
Adds an error display block to the specified page element, with specified text and formatting. |
addErrorFromQueryResponse(container, response) |
String ID value that identifies the error object created, or null if the response didn't indicate an error. This is a unique value on the page, and can be used to remove the error or find its containing element. |
Pass a query response and error message container to this method: if the query response
indicates a query error, displays an error message in the specified page element. If the
query response is null, the method will throw a JavaScript error. Pass your
QueryResponse received in your query handler to this message to
display an error. It will also set the style of the display appropriate to the type (error
or warning, similar to |
removeError(id) |
Boolean: true if the error was removed; false otherwise. |
Removes the error specified by ID from the page. |
removeAll(container) |
None |
Removes all error blocks from a specified container. If the specified container does not exist, this will throw an error. |
getContainer(errorId) |
Handle to a DOM element holding the error specified, or null if it could not be found. |
Retrieves a handle to the container element holding the error specified by errorID. |
Events
Most visualizations fire events to indicate something has occurred. As a user of the chart, you would often want to listen to these events. If you code your own visualization, you might also want to trigger such events on your own.
The following methods enable developers to listen to events, remove existing event handlers or trigger events from inside a visualization.
addListener()
Call this method to register to receive events fired by a visualization hosted on your page. You should document what event arguments, if any, will be passed to the handling function.
google.visualization.events.addListener(source_visualization, event_name, handling_function)
Returns
A listener handler for the new listener. The handler can be used to later remove this listener if needed by calling google.visualization.events.removeListener().
Example
Here is an example of registering to receive the selection event
var table = new google.visualization.Table(document.getElementById('table_div')); table.draw(data, options); google.visualization.events.addListener(table, 'select', selectHandler); function selectHandler() { alert('A table row was selected'); }
addOneTimeListener()
This is identical to addListener()
, but is intended for events that should only be
listened to once. Subsequent throws of the event will not invoke the handling function.
An example of when this is useful: every draw causes a ready
event to be thrown. If
you want only the first ready
to execute your code, you'll want
addOneTimeListener
rather than addListener
.
removeListener()
Call this method to unregister an existing event listener.
google.visualization.events.removeListener(listener_handler)
removeAllListeners()
Call this method to unregister all event listeners of a specific visualization instance.
google.visualization.events.removeAllListeners(source_visualization)
trigger()
Called by visualization implementers. Call this method from your visualization to fire an event with an arbitrary name and set of values.
google.visualization.events.trigger(source_visualization, event_name, event_args)
Example
Here is an example of a visualization that throws a method named "select" when its onclick method is called. It does not pass back any values.
MyVisualization.prototype.onclick = function(rowIndex) { this.highlightRow(this.selectedRow, false); // Clear previous selection this.highlightRow(rowIndex, true); // Highlight new selection // Save the selected row index in case getSelection is called. this.selectedRow = rowIndex; // Trigger a select event. google.visualization.events.trigger(this, 'select', null); }
Standard Visualization Methods and Properties
Every visualization should expose the following set of required and optional methods and properties. However, note that there is no type checking to enforce these standards, so you should read the documentation for each visualization.
Note: These methods are in the namespace of the visualization, not the google.visualization namespace.
Constructor
The constructor should have the name of your visualization class, and return an instance of that class.
visualization_class_name(dom_element)
Example
var org = new google.visualization.OrgChart(document.getElementById('org_div'));
draw()
Draws the visualization on the page. Behind the scenes this can be fetching a graphic from a server or creating the graphic on the page using the linked visualization code. You should call this method every time the data or options change. The object should be drawn inside the DOM element passed into the constructor.
draw(data[, options])
Example
chart.draw(myData, {width: 400, height: 240, is3D: true, title: 'My Daily Activities'});
getAction()
This is optionally exposed by visualizations that have tooltips and allow tooltip actions.
Returns the tooltip action object with the requested actionID
.
Example:
// Returns the action object with the ID 'alertAction'. chart.getAction('alertAction');
getSelection()
This is optionally exposed by visualizations that want to let you access the currently selected data in the graphic.
selection_array getSelection()
Returns
selection_array An array of selected objects, each one describing a data
element in the underlying table used to create the visualization (a DataView
or
a DataTable
). Each object has properties row
and/or column
,
with the index of the row and/or column of the selected item in the underlying
DataTable
. If the row
property is null, then the selection is a column;
if the column
property is null, then the selection is a row; if both are non-null,
then it is a specific data item. You can call the
DataTable.getValue()
method to get the value of the
selected item. The retrieved array can be passed into
setSelection()
.
Example
function myClickHandler(){ var selection = myVis.getSelection(); var message = ''; for (var i = 0; i < selection.length; i++) { var item = selection[i]; if (item.row != null && item.column != null) { message += '{row:' + item.row + ',column:' + item.column + '}'; } else if (item.row != null) { message += '{row:' + item.row + '}'; } else if (item.column != null) { message += '{column:' + item.column + '}'; } } if (message == '') { message = 'nothing'; } alert('You selected ' + message); }
removeAction()
This is optionally exposed by visualizations that have tooltips and allow tooltip actions.
Removes the tooltip action object with the requested actionID
from your chart.
Example:
// Removes an action from chart with the ID of 'alertAction'. chart.removeAction('alertAction');
setAction()
This is optionally exposed by visualizations that have tooltips and allow tooltip actions. It works only for core charts (bar, column, line, area, scatter, combo, bubble, pie, donut, candlestick, histogram, stepped area).
Sets a tooltip action to be executed when the user clicks on the action text.
setAction(action object)
The setAction
method takes an object as its action parameter. This object should
specify 3 properties: id
— the ID of the action being set, text
—the text that should appear in the tooltip for the action, and action
— the function that should be run when a user clicks on the action text.
Any and all tooltip actions should be set prior to calling the chart's draw()
method.
Example:
// Sets a tooltip action which will pop an alert box on the screen when triggered. chart.setAction({ id: 'alertAction', text: 'Trigger Alert', action: function() { alert('You have triggered an alert'); } });
The setAction
method can also define two additional properties: visible
and enabled
. These properties should be functions that return boolean
values indicating if the tooltip action will be visible and/or enabled.
Example:
// The visible/enabled functions can contain any logic to determine their state // as long as they return boolean values. chart.setAction({ id: 'alertAction', text: 'Trigger Alert', action: function() { alert('You have triggered an alert'); }, visible: function() { return true; }, enabled: function() { return true; } });
setSelection()
Optionally selects a data entry in the visualization—for example, a point in an area chart, or a bar
in a bar chart. When this method is called, the visualization should visually indicate what the
new selection is. The implementation of setSelection()
should not fire a
"select" event. Visualizations may ignore part of the selection. For example, a table
that can show only selected rows may ignore cell or column elements in its
setSelection()
implementation, or it can select the entire row.
Every time this method is called, all selected items are deselected, and the new selection list
passed in should be applied. There is no explicit way to deselect individual items; to deselect
individual items, call setSelection()
with the items to remain selected; to
deselect all elements, call setSelection()
, setSelection(null)
,
or setSelection([])
.
setSelection(selection_array)
Assorted Static Methods
This section contains various useful methods exposed in the google.visualization
namespace.
arrayToDataTable()
This method takes in a two-dimensional array and converts it to a DataTable.
The column data types are determined automatically by the data provided. Column data types can
also be specified using the object literal notation in the first row (the column header row) of
the array (i.e. {label: 'Start Date', type: 'date'}
).
Optional data roles may be used as well, but they
must be defined explicitly using object literal notation. Object literal notation may also be
used for any cell, allowing you to define Cell Objects).
Syntax
google.visualization.arrayToDataTable(twoDArray, opt_firstRowIsData)
Returns
A new DataTable
.
Examples
The following code demonstrates three ways to create the same DataTable
object:
// Version 1: arrayToDataTable method var data2 = google.visualization.arrayToDataTable([ [{label: 'Country', type: 'string'}, {label: 'Population', type: 'number'}, {label: 'Area', type: 'number'}, {type: 'string', role: 'annotation'}], ['CN', 1324, 9640821, 'Annotated'], ['IN', 1133, 3287263, 'Annotated'], ['US', 304, 9629091, 'Annotated'], ['ID', 232, 1904569, 'Annotated'], ['BR', 187, 8514877, 'Annotated'] ]); // Version 2: DataTable.addRows var data3 = new google.visualization.DataTable(); data3.addColumn('string','Country'); data3.addColumn('number','Population'); data3.addColumn('number','Area'); data3.addRows([ ['CN', 1324, 9640821], ['IN', 1133, 3287263], ['US', 304, 9629091], ['ID', 232, 1904569], ['BR', 187, 8514877] ]); // Version 3: DataTable.setValue var data = new google.visualization.DataTable(); data.addColumn('string','Country'); data.addColumn('number', 'Population'); data.addColumn('number', 'Area'); data.addRows(5); data.setValue(0, 0, 'CN'); data.setValue(0, 1, 1324); data.setValue(0, 2, 9640821); data.setValue(1, 0, 'IN'); data.setValue(1, 1, 1133); data.setValue(1, 2, 3287263); data.setValue(2, 0, 'US'); data.setValue(2, 1, 304); data.setValue(2, 2, 9629091); data.setValue(3, 0, 'ID'); data.setValue(3, 1, 232); data.setValue(3, 2, 1904569); data.setValue(4, 0, 'BR'); data.setValue(4, 1, 187); data.setValue(4, 2, 8514877);
drawChart()
This method creates a chart in a single call. The advantage of using this method is that it requires slightly less code, and you can serialize and save visualizations as text strings for reuse. This method does not return a handle to the created chart, so you cannot assign method listeners to catch chart events.
Syntax
google.visualization.drawChart(chart_JSON_or_object)
Property | Type | Required | Default | Description |
---|---|---|---|---|
chartType | String | Required | none |
The class name of the visualization. The google.visualization package name can
be omitted for Google charts. If the appropriate visualization library has not already been
loaded, this method will load the library for you if this is a Google visualization; you must
load third party visualizations explicitly. Examples: Table ,
PieChart , example.com.CrazyChart .
|
containerId | String | Required | none | The ID of the DOM element on your page that will host the visualization. |
options | Object | Optional | none |
An object describing the options for the visualization. You can use either JavaScript literal
notation, or provide a handle to the object. Example:
"options": {"width": 400, "height": 240,
"is3D": true, "title": "Company Performance"}
|
dataTable | Object | Optional | None |
A DataTable used to populate the visualization. This can be a literal JSON string
representation of a DataTable, as described above, or a handle to a
populated google.visualization.DataTable object, or a 2-dimensional array like
that accepted by
arrayToDataTable(opt_firstRowIsData=false)
.
You must specify either this property or the dataSourceUrl property.
|
dataSourceUrl | String | Optional | None |
A data source query to populate the chart data (for example, a
Google Spreadsheet). You must specify
either this property or the dataTable property.
|
query | String | Optional | None |
If specifying dataSourceUrl , you can optionally specify a SQL-like query string
using the Visualization query language
to filter or manipulate the data.
|
refreshInterval | Number | Optional | None |
How often, in seconds, the visualization should refresh its query source. Use this only when
specifying dataSourceUrl .
|
view | Object OR Array | Optional | None |
Sets a DataView initializer object, which acts as a filter over the underlying
data, as defined by either the dataTable or dataSourceUrl parameter.
You can pass in either a string or DataView initializer object, like that
returned by dataview.toJSON() .
Example: "view": {"columns": [1, 2]} You
can also pass in an array of DataView initializer objects, in which case the
first DataView in the array is applied to the underlying data to create a new
data table, and the second DataView is applied to the data table resulting from
application of the first DataView , and so on.
|
Examples
Creates a table chart based on a spreadsheet data source, and includes the query SELECT A,D WHERE D > 100 ORDER BY D
<script type="text/javascript"> google.charts.load('current'); // Note: No need to specify chart packages. function drawVisualization() { google.visualization.drawChart({ "containerId": "visualization_div", "dataSourceUrl": "https://spreadsheets.google.com/a/google.com/tq?key=pCQbetd-CptGXxxQIG7VFIQ&pub=1", "query":"SELECT A,D WHERE D > 100 ORDER BY D", "refreshInterval": 5, "chartType": "Table", "options": { "alternatingRowStyle": true, "showRowNumber" : true } }); } google.charts.setOnLoadCallback(drawVisualization); </script>
This next example creates the same table, but creates a DataTable
locally:
<script type='text/javascript'> google.charts.load('current'); function drawVisualization() { var dataTable = [ ["Country", "Population Density"], ["Indonesia", 117], ["China", 137], ["Nigeria", 142], ["Pakistan", 198], ["India", 336], ["Japan", 339], ["Bangladesh", 1045] ]; google.visualization.drawChart({ "containerId": "visualization_div", "dataTable": dataTable, "refreshInterval": 5, "chartType": "Table", "options": { "alternatingRowStyle": true, "showRowNumber" : true, } }); } google.charts.setOnLoadCallback(drawVisualization); </script>
This example passes in a JSON string representation of the chart, which you might have loaded from a file:
<script type="text/javascript"> google.charts.load('current'); var myStoredString = '{"containerId": "visualization_div",' + '"dataSourceUrl": "https://spreadsheets.google.com/a/google.com/tq?key=pCQbetd-CptGXxxQIG7VFIQ&pub=1",' + '"query":"SELECT A,D WHERE D > 100 ORDER BY D",' + '"refreshInterval": 5,' + '"chartType": "Table",' + '"options": {' + ' "alternatingRowStyle": true,' + ' "showRowNumber" : true' + '}' + '}'; function drawVisualization() { google.visualization.drawChart(myStoredString); } google.charts.setOnLoadCallback(drawVisualization); </script>
drawToolbar()
This is the constructor for the toolbar element that can be attached to many visualizations. This toolbar enables the user to export the visualization data into different formats, or to provide an embeddable version of the visualization for use in different places. See the toolbar page for more information and a code example.