/**
     * 销毁一个面板
     * @param key 唯一标识
     * @param newView 新面板
     */
    public void destroy(int key, IBaseView newView = null)
    {
        IBaseView oldView = this.getView(key);

        if (oldView != null)
        {
            this.unregister(key);
            oldView.destroy();
            oldView = null;
        }
        this.register(key, newView);
    }