Failed to instantiate the default view controller for UIMainStoryboardFile 'MyMain' - perhaps the designated entry point is not set?

自己新建了一个MyMain.storyboard，使用时报了一个错误如下：

2014-11-12 23:57:08.633 ToDoList[4666:2068874] Failed to instantiate the default view controller for UIMainStoryboardFile 'MyMain' - perhaps the designated entry point is not set?

原因分析：StoryBoard中没有一个view controller设置了Initial Scene。

解决方法：需要选择一个view conroller作为story board的第一个界面。将右边View Controller下的Is Initial View Controller的单选框勾上。