如何为RatingBar创建自定义弧形视图？

public class CustomRatingBar extends RatingBar {
    private Paint arcPaint;
    private int arcColor;
    private float arcWidth;

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

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

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

    private void init() {
        arcPaint = new Paint();
        arcPaint.setStyle(Paint.Style.STROKE);
        arcPaint.setAntiAlias(true);
        arcColor = Color.BLUE;
        arcWidth = 10f; // 假设默认弧形宽度为10px
    }

    @Override
    protected synchronized void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        RectF arcRect = new RectF(getPaddingLeft(), getPaddingTop(), getWidth() - getPaddingRight(), getHeight() - getPaddingBottom());
        arcPaint.setColor(arcColor);
        arcPaint.setStrokeWidth(arcWidth);

        float sweepAngle = getProgress() / getMax() * 360;
        canvas.drawArc(arcRect, 270, sweepAngle, false, arcPaint);
    }
}

<com.example.CustomRatingBar
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:numStars="5"
    android:rating="3.5"
    app:arcColor="#FF0000"
    app:arcWidth="5" />