自定义CardView只实现top圆角

public class CustomCardView extends CardView {
    float radius = SizeUtils.dp2px(5);
    Path path;
    public CustomCardView(Context context) {
        super(context);
        init();
    }

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

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

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        RoundRectShape roundRectShape = new RoundRectShape(new float[]{radius, radius, radius,
                radius, 0, 0,0,0}, null, null);
        ShapeDrawable shapeDrawable = new ShapeDrawable(roundRectShape);
        shapeDrawable.getPaint().setColor(Color.WHITE); // 设置你想要的背景颜色
        shapeDrawable.setBounds(0, 0, getWidth(), getHeight());
        canvas.drawPath(path,new Paint());
        shapeDrawable.draw(canvas);
        setBackground(shapeDrawable);
    }

    private void init() {
        path = new Path();
        RectF rect = new RectF(0, 0, getWidth(), getHeight());
        path.moveTo(0, 0); // 移动到左上角
        path.lineTo(0, radius); // 绘制左上角的线
        path.quadTo(0, 0, radius, 0); // 绘制左上角的圆角
        path.lineTo(rect.right - radius, 0); // 绘制顶部右边的线
        path.quadTo(rect.right, 0, rect.right, radius); // 绘制顶部右边的圆角
        path.lineTo(rect.right, rect.bottom); // 绘制底部右边的线
        path.lineTo(0, rect.bottom); // 绘制底部左边的线
        path.close(); // 关闭路径
    }
    public void setRadius(int number){
        radius = SizeUtils.dp2px(number);
        invalidate();
    }
}