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Flash Player 6.0.79.
Flash MX 2004.
Usage 1:
on(click){
...
}
Usage 2:
listenerObject= new Object();listenerObject.click = function(eventObject){...}radioButtonGroup.addEventListener("click",listenerObject)
Event; broadcast to all registered listeners when the mouse is clicked (pressed and released) over the radio button or if the radio button is selected by using the arrow keys. The event is also broadcast if the Spacebar or arrow keys are pressed when a radio button group has focus, but none of the radio buttons in the group are selected.
The first usage example uses an on() handler and must be attached directly to a RadioButton component 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 radio button myRadioButton, sends "_level0.myRadioButton" to the Output panel:
on(click){
trace(this);
}
The second usage example uses a dispatcher/listener event model. A component instance (radioButtonInstance) dispatches an event (in this case, click) and the event is handled by a function attached to 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. The event object has a set of properties that contains information about the event. You can use these properties to write code that handles the event. Finally, you call the UIEventDispatcher.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 about event objects, see Event Objects.
This example, written on a frame of the Timeline, sends a message to the Output panel when a radio button in the radioGroup is clicked. The first line of code creates a listener object called form. The second line defines a function for the click event on the listener object. Inside the function is a trace action 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. You can access instance properties from the target property (in this example, the RadioButton.selection property is accessed) The last line calls the UIEventDispatcher.addEventListener() method from radioGroup and passes it the click event and the form listener object as parameters, as in the following:
form = new Object();
form.click = function(eventObj){
trace("The selected radio instance is " + eventObj.target.selection);
}
radioGroup.addEventListener("click", form);
The following code also sends a message to the Output panel when radioButtonInstance is clicked. The on() handler must be attached directly to radioButtonInstance, as in the following:
on(click){
trace("radio button component was clicked");
}
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