Question

我构建一个静态库，链接其他框架，特别是CoreLocation。我想使用iOS 5提供的功能，但与4.3兼容。

当我在4.3版的iOS设备上启动它时，我的应用程序崩溃时出现此错误：

Date/Time:       2012-08-22 16:44:53.900 +0200
OS Version:      iPhone OS 4.3.3 (8J3)
Report Version:  104

Exception Type:  EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x00000001, 0xe7ffdefe
Crashed Thread:  0

Dyld Error Message:
  Symbol not found: _UIKeyboardDidChangeFrameNotification

我遇到的问题在这篇文章中有描述：iOS 4 app crashes at startup on iOS 3.1.3: Symbol not found: __NSConcreteStackBlock。

但是在构建静态库时如何处理？我设置-weak-lSystem标志时无法编译。这是一个痕迹：

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: -dynamic not specified, -all_load invalid
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: -dynamic not specified the following flags are invalid: -ObjC 
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: can't locate file for: -weak-lSystem
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: -weak-lSystem is not an object file (not allowed in a library)
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk/usr/lib/libxml2.2.dylib is a dynamic library, not added to the static library
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk/usr/lib/libxml2.2.dylib is a dynamic library, not added to the static library
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk/usr/lib/libz.dylib is a dynamic library, not added to the static library
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk/usr/lib/libz.dylib is a dynamic library, not added to the static library
Command /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool failed with exit code 1

解决

请参阅下面接受的答案，不要忘记将不同版本中使用的库标记为Xcode中的Optional。例如：我使用iOS 5的UIKit新通知，但我的部署目标是4.3，所以我需要将此库标记为可选，以使工作正常。 CoreLocation CLGeocoder新推出的iOS 5类也是如此。

Answer 1

问题是UIKeyboardDidChangeFrameNotification在iOS 4上不可用，因此动态加载程序（Dyld）失败。

从静态库开发人员的角度来看，您不必执行任何操作。 -weak-lSystem标志应该在Xcode项目中设置，该项目使用应用程序的静态库（参见问题中提到的帖子） - 而不是在静态库的项目中。

静态库和-weak-lSystem

1 个答案: