How to convert a Drawable to a Bitmap?

Question

I would like to set a certain Drawable as the device\'s wallpaper, but all wallpaper functions accept Bitmaps only. I cannot use WallpaperMan

Answer 1

A Drawable can be drawn onto a Canvas, and a Canvas can be backed by a Bitmap:

(Updated to handle a quick conversion for BitmapDrawables and to ensure that the Bitmap created has a valid size)

public static Bitmap drawableToBitmap (Drawable drawable) {
    if (drawable instanceof BitmapDrawable) {
        return ((BitmapDrawable)drawable).getBitmap();
    }

    int width = drawable.getIntrinsicWidth();
    width = width > 0 ? width : 1;
    int height = drawable.getIntrinsicHeight();
    height = height > 0 ? height : 1;

    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap); 
    drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
    drawable.draw(canvas);

    return bitmap;
}