如何以编程方式向我的ImageView添加圆角边框？

// 获取ImageView实例
ImageView imageView = findViewById(R.id.imageView);

// 加载图片资源到Bitmap
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.image);

// 创建BitmapShader对象
BitmapShader shader = new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);

// 创建Paint对象
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(shader);

// 创建RectF对象
RectF rectF = new RectF(0, 0, imageView.getWidth(), imageView.getHeight());

// 绘制圆角矩形
Canvas canvas = new Canvas(bitmap);
canvas.drawRoundRect(rectF, 20, 20, paint);

// 设置ImageView的背景
imageView.setBackground(new BitmapDrawable(getResources(), bitmap));