function onSourceDownloadProgressChanged(sender, eventArgs) {
   // var textBlock = sender.findName("txtInit");
    var canvas = sender.findName("backGround");
    var bg = sender.findName("bg2");

    var rectContainer = sender.findName("rectContainer");
    var rectFill = sender.findName("rectFill");
    var rectFillTransform = sender.findName("rectFillTransform");

    canvas.width = document.body.clientWidth;
    canvas.height = document.body.clientHeight;
    var totalWidth = document.body.clientWidth;
    var totalHeight = document.body.clientHeight;
//    var textWidth = textBlock.actualWidth;
//    var textHeight = textBlock.actualHeight;
//    textBlock.SetValue("Canvas.Left", 0.5 * totalWidth - 0.5 * textWidth);
//    textBlock.SetValue("Canvas.Top", 0.5 * totalHeight - 0.5 * textHeight);

    rectContainer.SetValue("Canvas.Left", 0.5 * totalWidth - 50);
    rectFill.SetValue("Canvas.Left", 0.5 * totalWidth - 50);
    rectContainer.SetValue("Canvas.Top", 0.5 * totalHeight - 2.5);
    rectFill.SetValue("Canvas.Top", 0.5 * totalHeight - 2.5);
    rectFillTransform.scaleX = eventArgs.progress;
}