Screen  - AS3

package
{
    import flash.display.Screen;
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.events.KeyboardEvent;
    import flash.geom.Rectangle;
    import flash.ui.Keyboard;

    public class DockingWindow extends Sprite
    {
        private const dockedWidth:uint = 80;
        private const dockedHeight:uint = 80;
        
        public function DockingWindow():void{
            stage.align = StageAlign.TOP_LEFT;
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.addEventListener(KeyboardEvent.KEY_DOWN,onKey);
            dockLeft();
        }
        
        private function onKey(event:KeyboardEvent):void{
            switch(event.keyCode){
                case Keyboard.LEFT :
                    dockLeft();
                    break;
                case Keyboard.RIGHT :
                    dockRight();
                    break;
                case Keyboard.UP :
                    dockTop();
                    break;
                case Keyboard.DOWN :
                    dockBottom();
                    break;
                case Keyboard.SPACE :
                    stage.nativeWindow.close();
            }    
        }
        
        public function dockLeft():void{
            var screen:Screen = getCurrentScreen();
            stage.nativeWindow.x = screen.visibleBounds.left;
            stage.nativeWindow.y = screen.visibleBounds.top;
            stage.nativeWindow.height = screen.visibleBounds.height;
            stage.stageWidth = dockedWidth;
            drawContent();
        }
        
        public function dockRight():void{
            var screen:Screen = getCurrentScreen();
            stage.nativeWindow.x = screen.visibleBounds.width - dockedWidth;            
            stage.nativeWindow.y = screen.visibleBounds.top;
            stage.stageWidth = dockedWidth;
            stage.nativeWindow.height = screen.visibleBounds.height;
            drawContent();
        }
        
        public function dockTop():void{
            var screen:Screen = getCurrentScreen();
            stage.nativeWindow.x = screen.visibleBounds.left;
            stage.nativeWindow.y = screen.visibleBounds.top;
            stage.nativeWindow.width = screen.visibleBounds.width;
            stage.stageHeight = dockedHeight;
            drawContent();
        }
        
        public function dockBottom():void{
            var screen:Screen = getCurrentScreen();
            stage.nativeWindow.x = screen.visibleBounds.left;
            stage.nativeWindow.y = screen.visibleBounds.height - dockedHeight;
            stage.nativeWindow.width = screen.visibleBounds.width;
            stage.stageHeight = dockedHeight;    
            drawContent();        
        }
        
        private function getCurrentScreen():Screen{
            return Screen.getScreensForRectangle(stage.nativeWindow.bounds)[0];
        }
        
        private function drawContent():void{
            const size:int = 60;
            const pad:int = 10;
            var numHSquares:int = Math.floor(stage.stageWidth/(size + pad));
            var numVSquares:int = Math.floor(stage.stageHeight/(size + pad));
            with (graphics){
                clear();
                lineStyle(1);
                beginFill(0x3462d5,.7);
                for(var i:int = 0; i < numHSquares; i++){
                    for(var j:int = 0; j < numVSquares; j++){                
                            drawRect((i * (size + pad)) + pad, (j * (size + pad)) + pad, size, size);
                    }
                }
                endFill();
            }
        }
    }
}