Xcode7 &&iOS9一些新特性 记录

1.bitcode

在编译时出现一个错误：libWeChatSDK.a(AppCommunicate.o)' does not contain bitcode. You must rebuild it with bitcode enabled (Xcode setting ENABLE_BITCODE), obtain an updated library from the vendor, or disable bitcode for this target. for architecture arm64

 后面一句话意思是：让第三方库支持，或者关闭target的bitcode选项

所以解决方法是在 build setting 里面找到 Enable bitcode 将其YES 改为 NO；

查了下资料，得知原因如下：

Bitcode is an intermediate representation of a compiled program. Apps you upload to iTunes Connect that contain bitcode will be compiled and linked on the App Store. Including bitcode will allow Apple to re-optimize your app binary in the future without the need to submit a new version of your app to the store.

说的是bitcode是被编译程序的一种中间形式的代码。包含bitcode配置的程序将会在App store上被编译和链接。bitcode允许苹果在后期重新优化我们程序的二进制文件，而不需要我们重新提交一个新的版本到App store上。

Bitcode. When you archive for submission to the App Store, Xcode will compile your app into an intermediate representation. The App Store will then compile the bitcode down into the 64 or 32 bit executables as necessary.

当我们提交程序到App store上时，Xcode会将程序编译为一个中间表现形式(bitcode)。然后App store会再将这个botcode编译为可执行的64位或32位程序。

作用其实就是用来优化app大小的，

2.ios模拟器无法联网

 编译报错：the resource could not be loaded because the App Transport Security 

这是因为苹果加大安全的管控，将以往HTTP协议强制改为HTTPS协议，，根本解决办法改协议，

临时解决办法在Info.plist中添加  NSAppTransportSecurity 类型  Dictionary 

Dictionary 下添加  NSAllowsArbitraryLoads 类型 Boolean ,值设为  YES

或者直接产看info.plist 的源代码 ，在字典里面里面添加以下内容

 <key>NSAppTransportSecurity</key>

    <dict>

        <key>NSAllowsArbitraryLoads</key>

        <true/>

    </dict>