Package | mx.charts |
Class | public class CategoryAxis |
Inheritance | CategoryAxis AxisBase EventDispatcher Object |
Implements | IAxis |
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
You are not required to explicitly set the dataProvider
property
on a CategoryAxis. A CategoryAxis used in a chart inherits its
dataProvider
property from the containing chart.
While you can use the same data provider to provide data to the chart and categories to the CategoryAxis, a CategoryAxis can optimize rendering if its data provider is relatively static. If possible, ensure that the categories are relatively static and that changing data is stored in separate data providers.
The dataProvider
property can accept
either an array of strings or an array of records (Objects)
with a property that specifies the category name.
If you specify a categoryField
property,
the CategoryAxis assumes that the data provider is an array of Objects.
If the value of the categoryField
property is null
,
the CategoryAxis assumes that the data provider is an array of Strings.
The <mx:CategoryAxis>
tag inherits all the properties
of its parent classes and adds the following properties:
<mx:CategoryAxis Properties categoryField="null" dataFunction="No default" dataProvider="No default" labelFunction="No default" padding="Default depends on chart type" ticksBetweenLabels="true" />
More examples
Learn more
Property | Defined By | ||
---|---|---|---|
baseline : Number [read-only]
The baseline position for the axis. | CategoryAxis | ||
categoryField : String
Specifies the field of the data provider
containing the text for the labels. | CategoryAxis | ||
chartDataProvider : Object [write-only]
The data provider assigned to the enclosing chart. | AxisBase | ||
constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | ||
dataFunction : Function
Specifies a method that returns the value that should be used as
categoryValue for current item.If this property is set, the return
value of the custom data function takes precedence over
categoryField
The custom dataFunction has the following signature:
function_name (axis:CategoryAxis, item:Object):Object { ... | CategoryAxis | ||
dataProvider : Object
Specifies the data source containing the label names. | CategoryAxis | ||
displayName : String
The name of the axis. | AxisBase | ||
labelFunction : Function
Specifies a function that defines the labels that are generated
for each item in the CategoryAxis's dataProvider. | CategoryAxis | ||
padding : Number
Specifies the padding added to either side of the axis
when rendering data on the screen. | CategoryAxis | ||
ticksBetweenLabels : Boolean
Specifies the location of major tick marks on the axis,
relative to the category labels. | CategoryAxis | ||
title : String
The text for the title displayed along the axis. | AxisBase | ||
unitSize : Number [read-only]
The size of one unit of data as represented by this axis. | AxisBase |
Method | Defined By | ||
---|---|---|---|
Constructor. | CategoryAxis | ||
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object with an EventDispatcher object so that the listener
receives notification of an event. | EventDispatcher | ||
Triggers events that inform the range object
when the chart data has changed. | AxisBase | ||
Dispatches an event into the event flow. | EventDispatcher | ||
Filters a set of values of arbitrary type
to a set of numbers that can be mapped. | CategoryAxis | ||
Formats values for display in DataTips. | CategoryAxis | ||
Determines the range to estimate what the axis labels should be. | CategoryAxis | ||
Gets the labels text that is rendered. | CategoryAxis | ||
Checks whether the EventDispatcher object has any listeners registered for a specific type
of event. | EventDispatcher | ||
Indicates whether an object has a specified property defined. | Object | ||
Maps a position along the axis back to a numeric data value. | CategoryAxis | ||
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | ||
Converts a set of values of arbitrary type
to a set of numbers that can be transformed into screen coordinates. | CategoryAxis | ||
Determines how the axis handles overlapping labels. | CategoryAxis | ||
Indicates whether the specified property exists and is enumerable. | Object | ||
Invoked when an AxisRenderer is unable to cleanly render
the labels without overlap, and would like the Axis object
to reduce the set of labels. | CategoryAxis | ||
Each DataTransform that makes use of an axis
registers itself with that axis. | AxisBase | ||
Removes a listener from the EventDispatcher object. | EventDispatcher | ||
Sets the availability of a dynamic property for loop operations. | Object | ||
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | ||
Returns the string representation of the specified object. | Object | ||
Maps a set of values from data space to screen space. | CategoryAxis | ||
Each DataTransform that makes use of an axis
registers itself with that axis. | AxisBase | ||
Updates the chart. | CategoryAxis | ||
Returns the primitive value of the specified object. | Object | ||
Checks whether an event listener is registered with this EventDispatcher object or any of
its ancestors for the specified event type. | EventDispatcher |
baseline | property |
baseline:Number
[read-only] Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
The baseline position for the axis. Some series, such as ColumnSeries or AreaSeries, use this value to define the base of a filled region when no minimum value is specified.
Implementation
public function get baseline():Number
categoryField | property |
categoryField:String
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Specifies the field of the data provider
containing the text for the labels.
If this property is null
, CategoryAxis assumes
that the dataProvider contains an array of Strings.
The default value is null.
Implementation
public function get categoryField():String
public function set categoryField(value:String):void
dataFunction | property |
dataFunction:Function
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Specifies a method that returns the value that should be used as
categoryValue for current item.If this property is set, the return
value of the custom data function takes precedence over
categoryField
The custom dataFunction
has the following signature:
function_name (axis:CategoryAxis, item:Object):Object { ... }
axis
is the current axis that uses this dataFunction
item
is the item in the dataProvider that is considered.
This function returns an object.
An example usage of a customized dataFunction
is to return a value
from a dataProvider that has items with nested fields
Implementation
public function get dataFunction():Function
public function set dataFunction(value:Function):void
Example
How to use this example
public function myFunction(axis:CategoryAxis,item:Object):Object { return(item.Country.State); }
dataProvider | property |
dataProvider:Object
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Specifies the data source containing the label names.
The dataProvider
can be an Array of Strings, an Array of Objects,
or any object that implements the IList or ICollectionView interface.
If the dataProvider
is an Array of Strings,
ensure that the categoryField
property
is set to null
.
If the dataProvider is an Array of Objects,
set the categoryField
property
to the name of the field that contains the label text.
Implementation
public function get dataProvider():Object
public function set dataProvider(value:Object):void
labelFunction | property |
labelFunction:Function
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Specifies a function that defines the labels that are generated
for each item in the CategoryAxis's dataProvider
.
If no labelFunction
is provided,
the axis labels default to the value of the category itself.
The labelFunction
method for a CategoryAxis
has the following signature:
function function_name(categoryValue:Object, previousCategoryValue:Object, axis:CategoryAxis, categoryItem:Object):String { ... }
Where:
categoryValue
is the value of the category to be represented.previousCategoryValue
is the value of the previous category on the axis.axis
is the CategoryAxis being rendered.categoryItem
is the item from thedataProvider
that is being represented.
Flex displays the returned String as the axis label.
If the categoryField
property is not set, the value
will be the same as the categoryValue
property.
Implementation
public function get labelFunction():Function
public function set labelFunction(value:Function):void
padding | property |
padding:Number
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Specifies the padding added to either side of the axis when rendering data on the screen. Set to 0 to map the first category to the very beginning of the axis and the last category to the end. Set to 0.5 to leave padding of half the width of a category on the axis between the beginning of the axis and the first category and between the last category and the end of the axis.
This is useful for chart types that render beyond the bounds of the category, such as columns and bars. However, when used as the horizontalAxis in a LineChart or AreaChart, it is reset to 0.
The default value is 0.5.
Implementation
public function get padding():Number
public function set padding(value:Number):void
ticksBetweenLabels | property |
ticksBetweenLabels:Boolean
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Specifies the location of major tick marks on the axis,
relative to the category labels.
If true
, tick marks (and any associated grid lines)
appear between the categories.
If false
, tick marks appear in the middle of the category,
aligned with the label.
Implementation
public function get ticksBetweenLabels():Boolean
public function set ticksBetweenLabels(value:Boolean):void
CategoryAxis | () | Constructor |
public function CategoryAxis()
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Constructor.
filterCache | () | method |
public function filterCache(cache:Array, field:String, filteredField:String):void
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Filters a set of values of arbitrary type to a set of numbers that can be mapped.
Parameters
cache:Array — An Array of objects where converted values
are read from and stored.
| |
field:String — The field of the objects in the cache Array
containing the pre-filtered values.
| |
filteredField:String — The field of the objects in the cache Array
where filtered values should be stored.
|
formatForScreen | () | method |
public function formatForScreen(value:Object):String
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Formats values for display in DataTips. Returns a user-readable string.
Parameters
value:Object — The value to convert to a String.
|
String — The text of the DataTip.
|
getLabelEstimate | () | method |
public function getLabelEstimate():AxisLabelSet
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Determines the range to estimate what the axis labels should be.
The axis almost immediately calls the getLabels()
method
to get the real values.
The axis uses the estimated values to adjust chart margins,
so any difference between the estimated labels and actual labels
(returned from the getLabels()
method) results in scaling
the labels to fit.
An axis need only return the minimum and maximum labels when returning an estimate. If the label set is fairly static, without depending on the size of the axis being rendered on screen, an axis can return the entire label set from this function, and mark the estimate as accurate.
ReturnsAxisLabelSet — An Array of AxisLabel objects.
|
getLabels | () | method |
public function getLabels(minimumAxisLength:Number):AxisLabelSet
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Gets the labels text that is rendered. When Flex calls this method, the axis has already determined the minimum length of the label.
Parameters
minimumAxisLength:Number — The minimum length of the axis, in pixels.
The axis can be longer than this value, but not shorter.
|
AxisLabelSet — An array of AxisLabel objects.
|
invertTransform | () | method |
public function invertTransform(value:Number):Object
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Maps a position along the axis back to a numeric data value.
Parameters
value:Number — The bound of the axis.
This parameter should be between 0 and 1,
with 0 representing the minimum bound of the axis, and 1 the maximum.
|
Object — An object containing the transformed value.
|
mapCache | () | method |
public function mapCache(cache:Array, field:String, convertedField:String, indexValues:Boolean = false):void
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Converts a set of values of arbitrary type to a set of numbers that can be transformed into screen coordinates.
Parameters
cache:Array — An Array of objects where converted values
are read from and stored.
| |
field:String — The field of the objects in the cache Array
containing the pre-converted values.
| |
convertedField:String — The field of the objects in the cache Array
where converted values should be stored.
| |
indexValues:Boolean (default = false ) — This parameter is true if the values being mapped
are index values, and false if they are natural data values.
|
preferDropLabels | () | method |
public function preferDropLabels():Boolean
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Determines how the axis handles overlapping labels.
Typically, numeric ranges return true
,
while discrete value-based ranges do not.
You can can override this property by setting it directly on the axis.
Boolean — true if labels can be dropped without loss of data;
otherwise, false .
|
reduceLabels | () | method |
public function reduceLabels(intervalStart:AxisLabel, intervalEnd:AxisLabel):AxisLabelSet
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Invoked when an AxisRenderer is unable to cleanly render the labels without overlap, and would like the Axis object to reduce the set of labels. The method is passed the two labels that are overlapping.
Parameters
intervalStart:AxisLabel — The start of the interval where labels overlap.
| |
intervalEnd:AxisLabel — The end of the interval where labels overlap.
|
AxisLabelSet — A new label set that resolves the overlap by reducing
the number of labels.
|
transformCache | () | method |
public function transformCache(cache:Array, field:String, convertedField:String):void
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Maps a set of values from data space to screen space.
Parameters
cache:Array — An Array of objects where mapped values
are read from and stored.
| |
field:String — The field of the objects in the cache Array
containing the pre-mapped values.
| |
convertedField:String — The field of the objects in the cache Array
where mapped values should be stored.
|
update | () | method |
public function update():void
Language Version: | ActionScript 3.0 |
Product Version: | Flex 3 |
Runtime Versions: | Flash Player 9, AIR 1.1 |
Updates the chart. This can be called multiple times per frame.
<?xml version="1.0"?> <!-- Simple example to demonstrate the HLOCChart control. --> <s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark" xmlns:mx="library://ns.adobe.com/flex/mx"> <fx:Script> <![CDATA[ import mx.collections.ArrayCollection; [Bindable] private var stockDataAC:ArrayCollection = new ArrayCollection( [ { Date: "25-Jul", Open: 40.55, High: 40.75, Low: 40.24, Close:40.31}, { Date: "26-Jul", Open: 40.15, High: 40.78, Low: 39.97, Close:40.34}, { Date: "27-Jul", Open: 40.38, High: 40.66, Low: 40, Close:40.63}, { Date: "28-Jul", Open: 40.49, High: 40.99, Low: 40.3, Close:40.98}, { Date: "29-Jul", Open: 40.13, High: 40.4, Low: 39.65, Close:39.95}, { Date: "1-Aug", Open: 39.00, High: 39.50, Low: 38.7, Close:38.6}, { Date: "2-Aug", Open: 38.68, High: 39.34, Low: 37.75, Close:38.84}, { Date: "3-Aug", Open: 38.76, High: 38.76, Low: 38.03, Close:38.12}, { Date: "4-Aug", Open: 37.98, High: 37.98, Low: 36.56, Close:36.69}, { Date: "5-Aug", Open: 36.61, High: 37, Low: 36.48, Close:36.86} ]); ]]> </fx:Script> <fx:Declarations> <!-- Define custom Stroke for the wick and ticks. --> <mx:SolidColorStroke id="s1" color="0x000000" weight="5" joints="bevel" caps="square"/> </fx:Declarations> <mx:Panel title="HLOCChart Control Example" height="100%" width="100%"> <mx:HLOCChart id="hlocchart" height="100%" width="100%" paddingRight="5" paddingLeft="5" showDataTips="true" dataProvider="{stockDataAC}"> <mx:verticalAxis> <mx:LinearAxis id="vaxis" baseAtZero="false" title="Price"/> </mx:verticalAxis> <mx:horizontalAxis> <mx:CategoryAxis id="haxis" categoryField="Date" title="Date"/> </mx:horizontalAxis> <mx:horizontalAxisRenderers> <mx:AxisRenderer axis="{haxis}" canDropLabels="true"/> </mx:horizontalAxisRenderers> <mx:series> <mx:HLOCSeries openField="Open" highField="High" lowField="Low" closeField="Close" stroke="{s1}" openTickStroke="{s1}" closeTickStroke="{s1}" openTickLength="7" closeTickLength="7" /> </mx:series> </mx:HLOCChart> </mx:Panel> </s:Application>
Thu Dec 6 2018, 01:12 PM -08:00