如何在android中创建圆角表面视图

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class RoundedSurfaceView extends SurfaceView implements SurfaceHolder.Callback {

    private float cornerRadius = 20f; // 圆角半径
    private Paint paint;

    public RoundedSurfaceView(Context context) {
        super(context);
        init();
    }

    public RoundedSurfaceView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public RoundedSurfaceView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        getHolder().addCallback(this);
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setColor(0xFFFFFFFF); // 白色背景
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        drawRoundedRect();
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
    }

    private void drawRoundedRect() {
        Canvas canvas = getHolder().lockCanvas();
        if (canvas != null) {
            try {
                RectF rect = new RectF(0, 0, getWidth(), getHeight());
                canvas.drawRoundRect(rect, cornerRadius, cornerRadius, paint);
            } finally {
                getHolder().unlockCanvasAndPost(canvas);
            }
        }
    }
}