xcode 未知类型名称“NSError”等
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Unknown type name 'NSError' and others
提问by badweasel
I'm not exactly a noob but I completley feel like one right now.
我不完全是一个菜鸟，但我现在完全感觉像一个。
I took an existing working app of mine. One that works under Xcode 5 and now works under Xcode 6. It compiles fine and runs. I started a new project in Xcode 6 and started to rebuild a new app shell using the structure of my working app. Moving over all of my standard libraries in it that I use in every app. I've done this several times under Xcode 5 with no problems.
我拿了我现有的工作应用程序。一个在 Xcode 5 下工作，现在在 Xcode 6 下工作。它编译得很好并运行。我在 Xcode 6 中开始了一个新项目，并开始使用我的工作应用程序的结构重建一个新的应用程序外壳。移动我在每个应用程序中使用的所有标准库。我已经在 Xcode 5 下多次这样做了，没有任何问题。
But now when I build I'm getting a lot of errors in a specific library (TBXML), but I don't get any of those errors on my other working project even though it has the same library. If I take those files out (so it's not compiling them) there are no errors and the app launches fine.
但是现在当我构建时，我在特定的库 (TBXML) 中遇到了很多错误，但是我在其他工作项目中没有遇到任何这些错误，即使它具有相同的库。如果我将这些文件取出（因此它不会编译它们），则不会出现错误并且应用程序可以正常启动。
I'm not even including the library yet. Same errors if I do or don't. But they are listed under Compile Sources and so they're compiling.
我什至还没有包括图书馆。如果我做或不做，同样的错误。但是它们列在编译源下，因此它们正在编译。
The errors are things like: ....blah..../TBXML/TBXML-Headers/TBXML.h:124:49: Unknown type name 'NSError'
错误是这样的： ....blah ..../TBXML/TBXML-Headers/TBXML.h:124:49: Unknown type name 'NSError'
on the line:
在线上：
typedef void (^TBXMLFailureBlock)(TBXML *tbxml, NSError *error);
....blah..../TBXML/TBXML-Headers/TBXML.h:126:71: Unknown type name 'NSString'
....等等..../TBXML/TBXML-Headers/TBXML.h:126:71: 未知类型名称“NSString”
on the line:
在线上：
typedef void (^TBXMLIterateAttributeBlock)(TBXMLAttribute *attribute, NSString *attributeName, NSString *attributeValue);
....blah..../TBXML/TBXML-Headers/TBXML.h:133:20: Cannot find interface declaration for 'NSObject', superclass of 'TBXML'
....blah..../TBXML/TBXML-Headers/TBXML.h:133:20: 找不到“NSObject”的接口声明，“TBXML”的超类
on the line:
在线上：
@interface TBXML : NSObject {
Items to check off the list:
要检查的项目：
- I do have all the proper frameworks including Foundation.
- no compiler flags for these files - which matches the old project.
- Build for and Target iOS is the same on both projects.
- I'm not looking for "don't use TBXML" as it works fine as is in the other project.
- 我确实拥有所有合适的框架，包括 Foundation。
- 这些文件没有编译器标志 - 与旧项目匹配。
- Build for 和 Target iOS 在两个项目上是相同的。
- 我不是在寻找“不要使用 TBXML”，因为它在其他项目中工作正常。
I'm assuming that it is some difference in project settings as my old project was created under Xcode 5 and this one under Xcode 6. But I've looked everywhere I know to look.
我假设项目设置存在一些差异，因为我的旧项目是在 Xcode 5 下创建的，而这个是在 Xcode 6 下创建的。但我已经查看了我知道的所有地方。
* UPDATE *
* 更新 *
This seems to fix it: TBXML in an iOS 8 extension fails to build
这似乎解决了它：iOS 8 扩展中的 TBXML 无法构建
I would like to know why though. The question is still out there. Why would one project need the #include and the other one not? The main difference is that one was created under Xcode 5 and the other under Xcode 6. But both projects are now in Xcode 6.
我想知道为什么。这个问题仍然存在。为什么一个项目需要#include 而另一个不需要？主要区别在于，一个是在 Xcode 5 下创建的，另一个是在 Xcode 6 下创建的。 但是这两个项目现在都在 Xcode 6 中。
回答by badweasel
Prefix Headers!!!
前缀头！！！
Thanks Hot Licks - you lead me to the answer. In my old project I had this:
感谢 Hot Licks - 你带我找到答案。在我的旧项目中，我有这个：
And in the new project I didn't. The contents of that file are:
而在新项目中我没有。该文件的内容是：
#import <Availability.h>
#ifndef __IPHONE_5_0
#warning "This project uses features only available in iOS SDK 5.0 and later."
#endif
#ifdef __OBJC__
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#endif
So basically every file had Foundation and UIKit included. So on the new project there were times when these were needed and not included. Perhaps apple read this: http://qualitycoding.org/precompiled-headers/
所以基本上每个文件都包含 Foundation 和 UIKit。因此，在新项目中，有时需要但不包括这些。也许苹果读过这个：http: //qualitycoding.org/precompiled-headers/
