MainActivity.java 文件源码

private void cropImageByPath() {
    //closing the path now.
    clipPath.close();
    //setting the fill type to inverse, so that the outer part of the selected path gets filled.
    clipPath.setFillType(FillType.INVERSE_WINDING);
    Paint xferPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    xferPaint.setColor(Color.BLACK);
    canvas.drawPath(clipPath, xferPaint);
    xferPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
    canvas.drawBitmap(alteredBitmap, 0, 0, xferPaint);
}