我刚刚在OS X（10.7.2）中完成了MonoDevelop 3.0的全新安装，然后对MonoMac进行了Git检查。我无法构建MonoMac存储库中包含的任何示例，每次输出显示构建成功后，我都会收到相同的错误：
Build failed. Object reference not set to an instance of an object
完整的样本构建输出：
Cleaning Solution: Fire (Debug)
Cleaning: Fire (Debug)
Removing output files...
Clean complete
Building Solution: Fire (Debug)
Building: Fire (Debug)
Performing main compilation...
/Library/Frameworks/Mono.framework/Versions/2.10.9/bin/dmcs /noconfig "/out:/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.exe" "/r:/Library/Frameworks/Mono.framework/Versions/2.10.9/lib/mono/4.0/System.dll" "/r:/Library/Frameworks/Mono.framework/Versions/2.10.9/lib/mono/4.0/System.Xml.dll" "/r:/Library/Frameworks/Mono.framework/Versions/2.10.9/lib/mono/4.0/System.Core.dll" "/r:/Library/Frameworks/Mono.framework/Versions/2.10.9/lib/mono/4.0/System.Xml.Linq.dll" "/r:/Library/Frameworks/Mono.framework/Versions/2.10.9/lib/mono/4.0/System.Drawing.dll" "/r:/Applications/MonoDevelop.app/Contents/MacOS/lib/monodevelop/AddIns/MonoDevelop.MonoMac/MonoMac.dll" /nologo /warn:4 /debug:full /optimize- /codepage:utf8 "/define:DEBUG" /t:exe "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainWindow.cs" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainWindowController.cs" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainWindow.xib.designer.cs" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/Main.cs" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/AppDelegate.cs" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainMenu.xib.designer.cs"
Compiling interface definitions
/Developer/usr/bin/ibtool --errors --warnings --notices --output-format human-readable-text --compile "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/Resources/MainWindow.nib" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainWindow.xib"
/* com.apple.ibtool.document.warnings */
/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainWindow.xib:2: warning: Content rectangle not entirely on screen with the menu bar (May not be completely visible for all screen resolutions and configurations) [9]
/Developer/usr/bin/ibtool --errors --warnings --notices --output-format human-readable-text --compile "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/Resources/MainMenu.nib" "/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/MainMenu.xib"
Copying content files
Copying '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.exe' to '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/MonoBundle/Fire.exe'
Copying '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.exe.mdb' to '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/MonoBundle/Fire.exe.mdb'
Copying '/Applications/MonoDevelop.app/Contents/MacOS/lib/monodevelop/AddIns/MonoDevelop.MonoMac/MonoMac.dll' to '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/MonoBundle/MonoMac.dll'
Copying '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/fire.png' to '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/Resources/fire.png'
Copying '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/smoke.png' to '/Users/dave/Dropbox/Code/MonoMac/monomac/samples/Fire/bin/Debug/Fire.app/Contents/Resources/smoke.png'
Build complete -- 0 errors, 0 warnings
Updating application manifest
---------------------- Done ----------------------
Build successful.
Build failed. Object reference not set to an instance of an object
我在这里做错了什么？
答案 0 :(得分：3)
这是一个已知问题。问题是MonoDevelop无法在您的系统上找到MacOSX sdk（可能是您使用的是早于4.3的Xcode版本？）。
我正在为MonoDevelop 3.0.2进行修复
答案 1 :(得分：1)
对我来说，事实是我在Info.plist文件中遇到了IDE无法识别的错误。只需要解决冲突并重建。