Macromedia flex 2-migrating applications to flex 2 Manual De Usuario

Binding from a property

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The Flex compiler automatically generates an event named 

propertyChange

 for all public 

properties so the properties can be used as the source of a data binding expression. In this case, 
specifying the 

[Bindable]

 metadata tag with no event is the same as specifying the following:

[Bindable(event="propertyChange")]

Binding from a single property

To make a single property usable as the source for a data binding expression, add the 

[Bindable]

 metadata tag before the property declaration. The property can be public, 

protected, or private. 

Flex 1.5:

var foo:String; // You could bind to this in 1.5

Flex 2:

[Bindable]
public var foo:String;

The Flex compiler automatically generates an event named 

propertyChange

 for all public 

properties so the properties can be used as the source of a data binding expression. In this case, 
specifying the 

[Bindable]

 metadata tag with no event is the same as specifying the following:

[Bindable(event="propertyChange")]

Binding from a property defined by a setter and getter 
method

In Flex 1.5, you used the 

[ChangeEvent]

 metadata tag on setter/getter pairs. In Flex 2, you 

replace the 

[ChangeEvent]

 metadata tag with the 

[Bindable]

 metadata tag and dispatch the 

event in the method. This strategy also applies to other methods that dispatched custom 
events.

Flex 1.5:

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

return _maxFontSize;

}

Flex 2:

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

return _maxFontSize;

}