ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Touch, multitouch and gesture input
Touch event handling
Flash Player 10.1 and later, Adobe AIR 2 and later
Basic touch events are handled the same way you handle other events, like mouse events, in ActionScript. You can
listen for a series of touch events defined by the event type constants in the TouchEvent class.
Note: For multiple touch point input (such as touching a device with more than one finger), the first point of contact
dispatches a mouse event and a touch event.
To handle a basic touch event:
1 Set your application to handle touch events by setting the flash.ui.Multitouch.inputMode property to
MultitouchInputMode.TOUCH_POINT.
2 Attach an event listener to an instance of a class that inherits properties from the InteractiveObject class, such as
Sprite or TextField.
3 Specify the type of touch event to handle.
4 Call an event handler function to do something in response to the event.
For example, the following code displays a message when the square drawn on mySprite is tapped on a touch-enabled
screen:
Multitouch.inputMode=MultitouchInputMode.TOUCH_POINT;
var mySprite:Sprite = new Sprite();
var myTextField:TextField = new TextField();
mySprite.graphics.beginFill(0x336699);
mySprite.graphics.drawRect(0,0,40,40);
addChild(mySprite);
mySprite.addEventListener(TouchEvent.TOUCH_TAP, taphandler);
function taphandler(evt:TouchEvent): void {
myTextField.text = "I've been tapped";
myTextField.y = 50;
addChild(myTextField);
}
Touch Event properties
When an event occurs, an event object is created. The TouchEvent object contains information about the location and
conditions of the touch event. You can use the properties of the event object to retrieve that information.
For example, the following code creates a TouchEvent object evt, and then displays the stageX property of the event
object (the x-coordinate of the point in the Stage space that the touch occurred) in the text field:
Last updated 6/6/2012
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