//Called when application is started.
function OnStart()
{
    app.SetOrientation("Portrait");
    //Create a layout with objects vertically centered.
    lay = app.CreateLayout( "Linear", "VCenter,FillXY" );    
    
    //Create an absolute layout so we can position objects.
    layAbs = app.CreateLayout( "Absolute" );    
    lay.AddChild( layAbs );

    //Create first image.
    img1 = app.CreateImage( null, 0.5, 0.3 );
    img1.SetColor("#66000088");
    img1.SetOnTouchDown(img_OnTouch);
    layAbs.AddChild( img1 );
    
    //Create second image.
    img2 = app.CreateImage( null, 0.5, 0.3 );
    img2.SetColor("#66880000");
    img2.SetPosition( 0.1,0.1 );
    img2.SetOnTouchDown(img_OnTouch);
    layAbs.AddChild( img2  );
 
    //Create third image in middle
    img3 = app.CreateImage( null, 0.5, 0.3 );
    img3.SetColor("#66008800");
    img3.SetPosition( 0.2,0.2 );
    img3.SetOnTouchDown(img_OnTouch);
    layAbs.AddChild( img3,1 );
    
    //Add layout to app.    
    app.AddLayout( lay );
}

//Called when user touches image
function img_OnTouch(){
  childToBack(layAbs, this)
}

function childToBack(layt, obj){
  if( layt.GetChildOrder( obj ) > 0 ){
    layt.RemoveChild(obj);
    layt.AddChild(obj,0);
  }
}