how to draw a Bitmap to a Canvas with a variable alpha
- by steelbytes
Hi, I'm trying to draw a Bitmap to a Canvas with a variable amount of alpha. But I only get nothing (when alpha<255) or the 'full' bitmap (when alpha==255).
Have also tried loading as a Drawable, and using drawable.setAlpha, but that gave the same result.
my init
BitmapFactory.Options opts = new BitmapFactory.Options();
opts.inScaled = false;
opts.inSampleSize = 1;
Bitmap img = BitmapFactory.decodeResource(getResources(),R.drawable.sample,opts);
my onDraw()
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG|Paint.FILTER_BITMAP_FLAG);
p.setColor((alpha<<24)+0xffffff); // alpha in range 0..255
canvas.drawBitmap(img, null, imgRect, p);
