Android:如何在画布上填充中心圆圈？

public class CircleView extends View {
    private Paint paint;

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

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

    private void init() {
        paint = new Paint();
        paint.setColor(Color.BLUE); // 设置圆圈的颜色
        paint.setStyle(Paint.Style.FILL); // 设置为实心圆
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        int centerX = getWidth() / 2;
        int centerY = getHeight() / 2;
        int radius = Math.min(centerX, centerY); // 圆圈半径为宽高的最小值

        canvas.drawCircle(centerX, centerY, radius, paint);
    }
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="vertical">

    <com.example.CircleView
        android:layout_width="200dp"
        android:layout_height="200dp" />

</LinearLayout>