获取圆角位图的方法

/**
  * 获取圆角位图的方法
  *
  * @param bitmap
  *            需要转化成圆角的位图
  * @param pixels
  *            圆角的度数，数值越大，圆角越大
  * @return 处理后的圆角位图
  */
 public static Bitmap toRoundCorner(Bitmap bitmap, int pixels) {
  Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888);
  Canvas canvas = new Canvas(output);
  final int color = 0xff424242;
  final Paint paint = new Paint();
  final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
  final RectF rectF = new RectF(rect);
  final float roundPx = pixels;
  paint.setAntiAlias(true);
  canvas.drawARGB(0, 0, 0, 0);
  paint.setColor(color);
  canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
  paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
  canvas.drawBitmap(bitmap, rect, rect, paint);
  return output;
 }

 

public static void setBackGp(Context c, ImageView imageView) {
  Drawable drawable = c.getResources().getDrawable(R.drawable.my_guanyu);
  BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
  Bitmap bitmap = bitmapDrawable.getBitmap();
  BitmapDrawable bbb = new BitmapDrawable(toRoundCorner(bitmap, 35));
  imageView.setBackgroundDrawable(bbb);
 }