Developing Android Applications with Adobe AIR

The GestureEvent Class

A GestureEvent is the interpretation of multiple points as a recognizable pattern. The Flash platform offers three gesture classes: GestureEvent, TransformGestureEvent, and PressAndTapGestureEvent. Gestures cannot be detected in sequence. The user must finish the first gesture, lift her fingers, and then start the next gesture.

Here is how to set a listener for the event type you want to receive:

Multitouch.inputMode = MultitouchInputMode.GESTURE;
stage.addEventListener(TransformGestureEvent.GESTURE_ZOOM, onZoom);

Gesture events have a phase property that is used to indicate the progress of the gesture. Its value is BEGIN when the finger is first pressed down; UPDATE while the finger is moving; and END when the finger leaves the screen. Another phase, ALL, is for events such as swipes or two-finger taps, which only return one phase.

A typical use for the phase property is to play one sound when the gesture begins and another sound when it ends:

import flash.ui.MultitouchInputMode;
import flash.events.GesturePhase;
import flash.events.TransformGestureEvent

function onZoom(event:TransformGestureEvent):void {
    if (event.phase == GesturePhase.BEGIN) {
        // play hello sound
    } else if (event.phase == GesturePhase.END) {
        // play good bye sound
    }
}

Gesture events have other properties related to position, as well as some that are relevant to their particular type. One gesture event, TransformGestureEvent, has many types, which we will discuss in the following subsections. ...