如何给Android应用设置圆角图片

public class MainActivity extends AppCompatActivity { private ImageView mImgRectRound; private ImageView mImgRound; @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  mImgRectRound = (ImageView) findViewById(R.id.img_rect_rounded);  mImgRound = (ImageView) findViewById(R.id.img_rounded);  rectRoundBitmap();  roundBitmap(); } private void rectRoundBitmap(){  //得到资源文件的BitMap  Bitmap image= BitmapFactory.decodeResource(getResources(),R.drawable.dog);  //创建RoundedBitmapDrawable对象  RoundedBitmapDrawable roundImg =RoundedBitmapDrawableFactory.create(getResources(),image);  //抗锯齿  roundImg.setAntiAlias(true);  //设置圆角半径  roundImg.setCornerRadius(30);  //设置显示图片  mImgRectRound.setImageDrawable(roundImg); } private void roundBitmap(){  //如果是圆的时候，我们应该把bitmap图片进行剪切成正方形， 然后再设置圆角半径为正方形边长的一半即可  Bitmap image = BitmapFactory.decodeResource(getResources(), R.drawable.dog);  Bitmap bitmap = null;  //将长方形图片裁剪成正方形图片  if (image.getWidth() == image.getHeight()) {   bitmap = Bitmap.createBitmap(image, image.getWidth() / 2 - image.getHeight() / 2, 0, image.getHeight(), image.getHeight());  } else {   bitmap = Bitmap.createBitmap(image, 0, image.getHeight() / 2 - image.getWidth() / 2, image.getWidth(), image.getWidth());  }  RoundedBitmapDrawable roundedBitmapDrawable = RoundedBitmapDrawableFactory.create(getResources(), bitmap);  //圆角半径为正方形边长的一半  roundedBitmapDrawable.setCornerRadius(bitmap.getWidth() / 2);  //抗锯齿  roundedBitmapDrawable.setAntiAlias(true);  mImgRound.setImageDrawable(roundedBitmapDrawable); }}