<window orientation="any" />Device Rotation
A very cool feature of today’s smartphones and tablets is that they recognize the orientation of the device in the physical world and may update the user interface accordingly.
To detect orientation changes in Starling, you may need to update your Lime project.xml configuration file.
Make sure that it defines the orientation setting in the <window> tag:
The value may be set to portrait, landscape, or any.
When that’s in place, you can listen for a RESIZE event on the Starling stage.
It is dispatched whenever the orientation changes.
After all, an orientation change always causes the stage size to change, as well (exchanging width and height).
Update the dimensions of the Starling viewPort and stage in the corresponding event handler.
stage.addEventListener(Event.RESIZE, onResize);
private function onResize(event:ResizeEvent):Void (1)
{
updateViewPort(event.width, event.height);
updatePositions(event.width, event.height);
}
private function updateViewPort(width:Int, height:Int):Void (2)
{
var current:Starling = Starling.current;
var scale:Float = current.contentScaleFactor;
stage.stageWidth = width / scale;
stage.stageHeight = height / scale;
current.viewPort.width = stage.stageWidth * scale;
current.viewPort.height = stage.stageHeight * scale;
}
private function updatePositions(width:Int, height:Int):Void (3)
{
// Update the positions of the objects that make up your game.
}| 1 | This event handler is called when the device rotates. |
| 2 | Updates the size of stage and viewPort depending on the current screen size in pixels. |
| 3 | Updates your user interface so that it fits the new orientation. |
Note that we had to update viewPort and stage size manually in the event listener. Per default, they will remain unchanged, which means that your application will appear cropped. The code above fixes that; it works for every scale factor.
The last part is going to be much harder: updating your user interface so that it fits into the new stage dimensions. This does not make sense for all games — but if it does, you should consider the additional effort. Your users will appreciate it!
| The Scaffold project included with Starling contains a possible implementation of this feature. |