xcode 为什么我会收到 Apple Mach-O 链接器 (ID) 错误？
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Why do I get an Apple Mach-O Linker (ID) Error?
提问by Sam Spencer
I know that this question had been asked many times, but every answer seems different. I have built my project and tried to run it, but I get this error:
我知道这个问题已经被问过很多次了，但每个答案似乎都不一样。我已经构建了我的项目并尝试运行它，但出现此错误：
Ld "/Users/******/Library/Developer/Xcode/DerivedData/Cypher_Bot-dxylepzskcnrtybprtuaotmycjjo/Build/Products/Debug-iphonesimulator/Cypher Bot.app/Cypher Bot" normal i386
cd "/Users/******/Xcode/iOS/Cypher Bot/Universal/Cypher Bot/Cypher Bot"
setenv MACOSX_DEPLOYMENT_TARGET 10.6
setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/clang -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk -L/Users/********/Library/Developer/Xcode/DerivedData/Cypher_Bot-dxylepzskcnrtybprtuaotmycjjo/Build/Products/Debug-iphonesimulator -F/Users/**********/Library/Developer/Xcode/DerivedData/Cypher_Bot-dxylepzskcnrtybprtuaotmycjjo/Build/Products/Debug-iphonesimulator -filelist "/Users/*******/Library/Developer/Xcode/DerivedData/Cypher_Bot-dxylepzskcnrtybprtuaotmycjjo/Build/Intermediates/Cypher Bot.build/Debug-iphonesimulator/Cypher Bot.build/Objects-normal/i386/Cypher Bot.LinkFileList" -mmacosx-version-min=10.6 -Xlinker -objc_abi_version -Xlinker 2 -fobjc-arc -Xlinker -no_implicit_dylibs -D__IPHONE_OS_VERSION_MIN_REQUIRED=50000 -framework Security -framework UIKit -framework Foundation -framework CoreGraphics -framework CoreData -o "/Users/********/Library/Developer/Xcode/DerivedData/Cypher_Bot-dxylepzskcnrtybprtuaotmycjjo/Build/Products/Debug-iphonesimulator/Cypher Bot.app/Cypher Bot"
Undefined symbols for architecture i386:
"_OBJC_CLASS_$_MFMailComposeViewController", referenced from:
objc-class-ref in CryptoMainViewController.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)
I also get this right below the message above:
我也在上面的消息下面得到了这个：
What does this mean? What do I do to fix it?
这是什么意思？我该怎么做才能修复它？
回答by rob mayoff
The error means that the linker can't find the class definition for MFMailComposeViewController. That class is defined in the MessageUIframework. Did you add the MessageUIframework to your target? If you don't know how to do that, read this: How to "add existing frameworks" in Xcode 4?
该错误意味着链接器找不到MFMailComposeViewController. 该类是在MessageUI框架中定义的。您是否将MessageUI框架添加到目标中？如果您不知道该怎么做，请阅读：如何在 Xcode 4 中“添加现有框架”？
