NinePatchDrawable无法转换为android.graphics.drawable.BitmapDrawable

Question

我在imageview中使用了可绘制的九个补丁，并使用下面的代码来获取位图，但是会发生此错误。

 Bitmap stickerBitmap = ((BitmapDrawable) Front.getDrawable()).getBitmap();

Answer 1

You cannot directly cast a NinePatchDrawable to a BitmapDrawable , since those are two different incompatible drawable types.

If you want to get a Bitmap from a non-BitmapDrawable you have to draw it with a Canvas onto a Bitmap:

Drawable drawable = Front.getDrawable();
Bitmap stickerBitmap = Bitmap.createBitmap(Front.getWidth(),
        Front.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(stickerBitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);

Note that your ImageView has to be layouted so that it has a non-zero size.