Adobe FLEX 2 - CREATING AND EXTENDING COMPONENTS Manual page 173

Example: Composite component
This section uses an example component, called ModalText and defined in the file
ModalText.as, that combines a Button control and a TextArea control. You use the Button
control to enable or disable text input in the TextArea control.
Defining event listeners for composite components
Custom components implement the
component, as the following example shows:
override protected function createChildren():void {
super.createChildren();
// Create and initialize the TextArea control.
if (!text_mc) {
text_mc = new TextArea();
...
text_mc.addEventListener("change", handleChangeEvent);
addChild(text_mc);
}
// Create and initialize the Button control.
if (!mode_mc) {
mode_mc = new Button();
...
mode_mc.addEventListener("click", handleClickEvent);
addChild(mode_mc);
}
}
The
createChildren()
register an event listener for the
event for the Button
click
class, as the following example shows:
// Handle events that are dispatched by the children.
private function handleChangeEvent(eventObj:Event):void {
dispatchEvent(new Event("change"));
}
// Handle events that are dispatched by the children.
private function handleClickEvent(eventObj:Event):void {
text_mc.editable = !text_mc.editable;
}
You can handle an event dispatched by a child of a composite component in the component.
In this example, the event listener for the Button control's
definition to toggle the
createChildren()
method also contains a call to the
event generated by the
change
control. These event listeners are defined within the ModalText
property of the TextArea control.
editable
method to create children of the
addEventListener()
TextArea
event is defined in the class
click
Example: Creating a composite component
method to
control, and for the
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