android 使图片显示 圆角

类似上面的效果，将方形图片 显示为圆角图

//获得圆角图片的方法      public Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){                    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);             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;      }