ActionScript 2.0 Components Language Reference 
ActionScript 2.0 Components Language Reference |
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| DateChooser component > DateChooser.change | |||
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Flash Player 6 (6.0.79.0).
Flash MX Professional 2004.
Usage 1:
var listenerObject:Object= new Object();listenerObject.change = function(eventObject:Object) {// ...};dateChooserInstance.addEventListener("change",listenerObject);
Usage 2:
on (change) {
//...
}
Event; broadcast to all registered listeners when a date is selected.
The first usage example uses a dispatcher/listener event model. A component instance (dataChooserInstance) dispatches an event (in this case, change) and the event is handled by a function, also called a handler, on a listener object (listenerObject) that you create. You define a method with the same name as the event on the listener object; the method is called when the event is triggered. When the event is triggered, it automatically passes an event object (eventObject) to the listener object method. Each event object has properties that contain information about the event. You can use these properties to write code that handles the event. Finally, you call the EventDispatcher.addEventListener() method on the component instance that broadcasts the event to register the listener with the instance. When the instance dispatches the event, the listener is called.
For more information, see EventDispatcher class.
The second usage example uses an on() handler and must be attached directly to a DateChooser instance. The keyword this, used inside an on() handler attached to a component, refers to the component instance. For example, the following code, attached to the date chooser my_dc, sends "_level0.my_dc" to the Output panel:
on (change) {
trace(this);
}
This example, written on a frame of the timeline, sends a message to the Output panel when a DateChooser instance called my_dc is changed. The first line of code creates a listener object called form. The second line defines a function for the change event on the listener object. Inside the function is a trace() statement that uses the event object that is automatically passed to the function, in this example eventObj, to generate a message. The target property of an event object is the component that generated the event (in this example, my_dc).
// Create listener object.
var dcListener:Object = new Object();
dcListener.change = function(evt_obj:Object) {
var thisDate:Date = evt_obj.target.selectedDate;
trace("date selected: " + thisDate);
};
// Add listener object to date chooser.
my_dc.addEventListener("change", dcListener);
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