Android中实现圆角图片的几种方法

public static 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;
}

bitmapShader = new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
paint.setShader(bitmapShader);
@Override
public void draw(Canvas canvas) {
  Rect bounds = getBounds();
  canvas.drawRoundRect(fillRect, radius, radius, paint);
  if (mBorderWidth > 0) {
    if (mIsCircle) {
      canvas.drawCircle(bounds.width() / 2, bounds.height() / 2, radius, strokePaint);
    }
    else {
      canvas.drawRoundRect(fillRect, radius, radius, strokePaint);
    }
  }
}

DisplayImageOptions optiOns= new DisplayImageOptions.Builder()
    .displayer(new RoundedBitmapDisplayer()) // display rounded bitmap
    .build();

@Override
protected void onDraw(Canvas canvas) {
  super.onDraw(canvas);
  if (src != null && dst != null) {
    int w = getMeasuredWidth(), h = getMeasuredHeight();
    int sc = canvas.saveLayer(0, 0, w, h, null,
      Canvas.MATRIX_SAVE_FLAG | Canvas.CLIP_SAVE_FLAG | Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
        | Canvas.FULL_COLOR_LAYER_SAVE_FLAG | Canvas.CLIP_TO_LAYER_SAVE_FLAG);
    canvas.drawBitmap(dst, 0, 0, paint); // 圆角矩形
    paint.setXfermode(mode); // new PorterDuffXfermode(PorterDuff.Mode.SRC_OUT);
    canvas.drawBitmap(src, 0, 0, paint); // 长方形
    paint.setXfermode(null);
    canvas.restoreToCount(sc);
  }
}