下载代码后运行时出现以下错误怎么解决？

1. Launch screens may not use instances of IBUIStoryboardEntryPointIndicator.
2. Launch screens may only have one top level object , which must be a UIView or a kind of UIViewcontroller.
3. Launch screens may not use instances of IBUISceneExitPlaceholder.

http://stackoverflow.com/questions/32444733/launch-screen-illegal-configuration-xcode-6-4