http://www.cnblogs.com/modaoyicheng/p/4828320.html
1.App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app‘s Info.plist file.
解决： 在iOS9 beta中，苹果将原http协议改成了https协议，使用 TLS1.2 SSL加密请求数据。
解决方法：
在info.plist 加入key
<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>
2<Error>: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_C
解决： info.plist 中删掉key UIViewControllerBasedStatusBarAppearance
