今天碰到一个很奇怪的问题，游戏中很多Button的缩放不是依靠中心点而缩放的，检查了一下，原来是RectTransform的pivot设置有问题，所以写了一个unity扩展工具，方便修改prefab的button

使用方法
选中prefab--------->选择这个扩展方法执行

[MenuItem("GameObject/DMTools/【Button】设置Button缩放为中心点缩放", priority = 21)]
    public static void SetPrivot()
    {
        double time = DateTime.Now.TimeOfDay.TotalMilliseconds;
        GameObject go = Selection.activeGameObject;
        if (null == go) return;
        //true代表 遍历未显示的游戏物体
        Button[] button = go.GetComponentsInChildren<Button>(true);
        Debug.Log("button.Length：" + button.Length);
        Animator ani;
        RectTransform trans;
        float pos_x = 0;
        float pos_y = 0;
        float rect_width = 0;
        float rect_height = 0;
        foreach (Button btn in button)
        {
            ani = btn.GetComponent<Animator>();
            if (ani == null || ani.runtimeAnimatorController.name != "Button_ScaleAni")
            {
                continue;
            }
            trans = btn.GetComponent<RectTransform>();
            pos_x = trans.anchoredPosition.x;
            rect_width = (float)((0.5 - trans.pivot.x) * trans.rect.width);
            pos_y = trans.anchoredPosition.y;
            rect_height = (float)((0.5 - trans.pivot.y) * trans.rect.height);
            //设置按钮position和pivot
            trans.anchoredPosition = new Vector2(pos_x + rect_width, pos_y + rect_height);
            trans.pivot = new Vector2(0.5f, 0.5f);
            Debug.Log("Set GameObject Name： " + trans.gameObject.name);
        }
        Debug.Log("Set pivot End," + (DateTime.Now.TimeOfDay.TotalMilliseconds - time) / 1000);
    }