From experience so far, you don't skin the View. You skin the ViewNavigatorApplication. First, create the custom skin:
public class DViewNavigatorApplicationSkin extends ViewNavigatorApplicationSkin
{
[Embed(source="assets/wine_240.jpg")]
protected var cornerImage:Class;
public function DViewNavigatorApplicationSkin()
{
super();
}
override protected function drawBackground(unscaledWidth:Number, unscaledHeight:Number):void
{
graphics.beginFill(0x000000);
graphics.drawRect(0,0, unscaledWidth, unscaledHeight);
graphics.endFill();
var ba:BitmapAsset = new cornerImage() as BitmapAsset;
var translateMatrix:Matrix = new Matrix();
translateMatrix.tx = unscaledWidth - ba.width;
translateMatrix.ty = unscaledHeight - ba.height;
graphics.beginBitmapFill(ba.bitmapData, translateMatrix);
graphics.drawRect(unscaledWidth - ba.width + 1, unscaledHeight - ba.height + 1, ba.width, ba.height);
graphics.endFill();
}
The contents of drawBackground docks the image to the lower right-hand corner of the display. You can draw anything in this function.
Then in the theme.css:
s|ViewNavigatorApplication
{
color: #ffffff;
focusColor: #ff9999;
skinClass: ClassReference("com.domain.skins.mobile.ThemeName.DViewNavigatorApplicationSkin");
}
s|View
{
backgroundAlpha: 0;
}
You draw the background image on the application itself. You then make the View totally transparent so that you can see the background image through it.
It may be possible to skin each individual view, but so far, it seems more practical to skin the application instead.