Drawing a View manually onto a Canvas does not preserve transparency

Question

When I draw a view, that contains transparent areas, due to its background image, these transparent areas turn black when the view is drawn to a canvas:

View v = getView();
v.measure(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
v.layout(0, 0, infoWindow.getMeasuredWidth(), infoWindow.getMeasuredWidth());
Bitmap b = Bitmap.createBitmap(v.getMeasuredWidth(), v.getMeasuredHeight(), Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(b);
//c.drawColor(Color.YELLOW); // yellow color does not show up
v.draw(c);

As the yellow background from the code snippet does not show up in the Bitmap, I conclude that v.draw(c) does not paint using transparency. If I draw a Drawable onto the canvas instead, its transparent areas are drawn correctly.

As the view is inflated from a layout file, I can observe that the same layout is rendered correctly by Android when being used within an action. So how can I draw a View onto a canvas while maintaining transparent areas?

Answer 1

Call v.setDrawingCacheEnabled(true) and v.getDrawingCache(). The second one will give you a Bitmap which you can draw.