Macromedia flex 2 Manuale

Metadata tags

53

You can specify the event name, as the following example shows:

[Bindable(event="changeShortNames")]
public function set shortNames(val:Boolean):void {

...
// Create and dispatch event. 
dispatchEvent(new Event("changeShortNames"));

}

// Get method. 
public function get shortNames():Boolean {

...

}

In this case, you are responsible for generating and dispatching the event, typically in the 
setter method. You can specify a 

[Bindable]

 tag that includes the 

event

 specification to 

name the event, even when you already specified the 

[Bindable]

 tag at the class level. 

The following example makes the 

maxFontSize

 and 

minFontSize

 properties that you 

defined as variables that can be used as the sources for data bindings:

// Define public vars for tracking font size.
[Bindable]
public var maxFontSize:Number = 15;
[Bindable]
public var minFontSize:Number = 5;

In the following example, you make a public property that you defined by using a setter and a 
getter method that is usable as the source for data binding The 

[Bindable]

 metadata tag 

includes the name of the event broadcast by the setter method when the property changes:

// Define private variable.
private var _maxFontSize:Number = 15;

[Bindable(event="maxFontSizeChanged")]
// Define public getter method.
public function get maxFontSize():Number {

return _maxFontSize;

}

if (value <= 30) {

_maxFontSize = value;

} else _maxFontSize = 30;

// Create event object. 
var eventObj:Event = new Event("maxFontSizeChanged");
dispatchEvent(eventObj);

}