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

Keyboard events

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Maintaining scope

Previously, you used the mx.utils.Delegate class to provide access to the document scope 
within an event handler. You would pass the Delegate object into a call to the 

addEventListener()

 method so that the listener would execute in that scope. This is no 

longer necessary. The event listener’s scope is now the class in which it is declared as a 
function, which is in most cases the scope you should expect; for example:

Flex 1.x:

addEventListener("click", mx.utils.Delegate.create(this, myListener)); 

Flex 2:

addEventListener(MouseEvent.CLICK, myListener); 

Using setCapture()

The 

setCapture()

 method has been removed. This method was added in earlier Beta releases 

of Flex 2 and was used to block events going to other (nested or non-nested) components 
during drag-and-drop operations and a few other interactions. However, in the nested 
situation, if one component called the 

setCapture()

 method, its parents and children could 

not.

If you require this functionality, you should use the capture phase of the event model by 
calling the 

stage.addEventListener("mouseXXX", mouseXXXHandler, true)

 method, 

where 

mouseXXX

 is the mouse event you want to block. You can then emulate the 

setCapture()

 method by calling the 

event.stopPropagation()

 method; however, Adobe 

does not recommend doing this because most components should ignore the event.

The 

removeCapture()

 method has also been removed.

Keyboard events

The 

code

 and 

ascii

 properties of the KeyboardEvent (formerly Event) object are now 

keyCode

 and 

charCode

.

In drag-and-drop examples in Flex 1.x, you could use 

Key.isDown()

 to detect a key that was 

pressed during the operation. In Flex 2, you use the 

shiftKey

, 

ctrlKey

, and 

altKey

 

properties on the KeyboardEvent object to detect keys that are pressed during the operation.