handle bitmap in postprocessor will lead to the bitmap has a black background

[wuyang102]

I try to show image with a bubble shape. And handle the bitmap in postprocessor. It runs normally on 5.0. But the image has a black background color on 4.4.2 even I set the background color to transparent.

Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_ATOP));

public CloseableReference<Bitmap> process(Bitmap bitmap, PlatformBitmapFactory platformBitmapFactory) {
        Matrix matrix = new Matrix();
        if (mScale != 1) {
            matrix.postScale(mScale, mScale);
        }

        CloseableReference<Bitmap> bitmapReference = platformBitmapFactory.createBitmap(mWidth, mHeight);
        Canvas canvas = new Canvas(bitmapReference.get());

        Resources resources = mRootView.getResources();
        NinePatchDrawable drawable = (NinePatchDrawable) resources.getDrawable(getBubbleResource());
        if (drawable != null) {
            drawable.setBounds(0, 0, mWidth, mHeight);
            drawable.draw(canvas);
        }
        canvas.drawBitmap(bitmap, matrix, mPaint);
        return CloseableReference.cloneOrNull(bitmapReference);
}

[plamenko]

Do bitmapReference.get().setHasAlpha(true);