ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Display programming
Stage dimension changes
When the stage dimensions change, the stage contents are scaled and repositioned as specified by the scaleMode and
align properties of the Stage object. In most cases, relying on the automatic behavior provided by the Stage
scaleMode settings does not produce good results. Instead you must re-layout or redraw your graphics and
components to support more than one aspect ratio. (Providing flexible layout logic also means that your application
will work better across devices with different screen sizes and aspect ratios.)
The following illustration demonstrates the effects of the different scaleMode settings when rotating a typical mobile
device:
Rotation from landscape to portrait aspect ratio
The illustration demonstrates the scaling behavior that occurs when rotating from a landscape aspect ratio to a portrait
aspect ratio with different scale modes. Rotating from portrait to landscape causes a similar set of effects.
Orientation change events
The Stage object dispatches two types of events that you can use to detect and react to orientation changes. Both stage
resize and orientationChange events are dispatched when auto-orientation is enabled.
The resize event is the best event to use when you are relying on auto-orientation to keep the display upright. When
the stage dispatches a resize event, relayout or redraw your content, as needed. The resize event is only dispatched
when the stage scale mode is set to noScale.
The orientationChange event can also be used to detect orientation changes. The orientationChange event is only
dispatched when auto-orientation is enabled.
Note: On some mobile platforms, the stage dispatches a cancelable orientationChanging event before dispatching the
resize or orientationChange events. Since the event is not supported on all platforms, avoid relying on it.
Last updated 6/6/2012
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