Xcode7、iOS9网络访问权限问题

调用网络访问的时候发现权限不够，报如下错误：
The resource could not be loaded because the App Transport Security policy requires the use of a secure connection.

查证iOS9.0后苹果的官方文档更新：
 https://developer.apple.com/library/ios/releasenotes/General/WhatsNewIniOS/Articles/iOS9.html#//apple_ref/doc/uid/TP40016198-DontLinkElementID_13

App Transport Security

App Transport Security (ATS) enforces best practices in the secure connections between an app and its back end. ATS prevents accidental disclosure, provides secure default behavior, and is easy to adopt; it is also on by default in iOS 9 and OS X v10.11.
You should adopt ATS as soon as possible, regardless of whether you’re creating a new app or updating an existing one.If you’re developing a new app, you should use HTTPS exclusively. If you have an existing app, you should use HTTPS as much as you can right
now, and create a plan for migrating the rest of your app as soon as possible. In addition, your communication through higher-level APIs needs to be encrypted using TLS version 1.2 with forward secrecy. If you try to make a connection that doesn’t follow this
requirement, an error is thrown. If your app needs to make a request to an insecure domain, you have to specify this domain in your app’s

Info.plist

file.

解决方法如下：

1.找到info.plist

2.添加NSAppTransportSecurity或App Transport Security Settings，Type为Dictionary

3.添加NSAllowsArbitraryLoads或Allow Arbitrary Loads，Type为Boolean,Value为YES