包装Monotouch类的ClassHandle返回null

Question

我在Monotouch中包装Objective-c库。问题是，在使用btouch生成DLL之后，以及当我尝试在示例应用程序中使用DLL中的某些类时，大多数类的类都会返回0x0。我调试了这个问题，并且我发现class_ptr（由Messaging类使用）也返回0x0。

我检查了构建输出（在MonoDevelop中构建项目之后），它看起来链接了我的本机库，但仍然出现相同的错误。构建输出包含在下面。问题是，我有定义为一个协议GDiOSDelegate如下

@protocol GDiOSDelegate 
@required 

- (void)handleEvent:(GDAppEvent*)anEvent; 
@end 

此协议通过GDiOS类使用（即我也包括在内），但它也需要作为handleEvent方法需要与从一些物体进行通信与UIApplicationDelegate交互UIApplicationDelegate（在Objective-C中使用库的等效示例代码有一个类A：NSObject）。

我这是在GDiOSDelegate结合我设置的typeof属性UIApplicationDelegate而不是NSObject的

[BaseType(typeof(UIApplicationDelegate))] 

所以，回来我是有错误后，我使用了一些方法的方式Monotouch绑定DLL，它抛出一个异常说AppDelegate没有实现UIApplicationDelegate。

[Register ("AppDelegate")] 
public partial class AppDelegate : GDiOSDelegate 
{...} 

即使我将UIApplicationDelegate而不是GDiOSDelegate作为基类，也会发生这种情况。

生成的输出：

Building: GDBinding (Debug) 

Build started 7/16/2012 9:03:46 AM. 
__________________________________________________ 
Project "/Users/thabetkacem/Projects/GDBinding/GDBinding/GDBinding.csproj" (Build target(s)): 

Target CreateGeneratedSourcesDir: 
    Created directory "obj/Debug/ios/" 

Target PrepareForBuild: 
    Configuration: Debug Platform: AnyCPU 

Target CopyFilesMarkedCopyLocal: 
    Copying file from '/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll' to '/Users/thabetkacem/Projects/GDBinding/GDBinding/bin/Debug/GDBinding.dll' 

Target GenerateSatelliteAssemblies: 
No input files were specified for target GenerateSatelliteAssemblies, skipping. 

Target GenerateBindings: 
    Tool /Developer/MonoTouch/usr/bin/btouch execution started with arguments: /d:DEBUG GDBinding.cs /s:StructsAndEnums.cs /tmpdir:obj/Debug/ios/ /sourceonly:obj/Debug/ios//sources.list 
GDBinding.cs(642,22): warning CS0465: Introducing `Finalize' method can interfere with destructor invocation. Did you intend to declare a destructor? 

Target CoreCompile: 
    Tool /Developer/MonoTouch/usr/bin/smcs execution started with arguments: /noconfig /debug:full /debug+ /optimize- /out:obj/Debug/GDBinding.dll /resource:libGD.a libGD.linkwith.cs Extra.cs AssemblyInfo.cs StructsAndEnums.cs obj/Debug/ios/ObjCRuntime/Messaging.g.cs obj/Debug/ios/GDBinding/GDCReadStream.g.cs obj/Debug/ios/GDBinding/GDCWriteStream.g.cs obj/Debug/ios/GDBinding/GDPersistentStoreCoordinator.g.cs obj/Debug/ios/GDBinding/GDFileSystem.g.cs obj/Debug/ios/GDBinding/GDDirectByteBuffer.g.cs obj/Debug/ios/GDBinding/GDSocketDelegate.g.cs obj/Debug/ios/GDBinding/GDSocket.g.cs obj/Debug/ios/GDBinding/GDHttpRequestDelegate.g.cs obj/Debug/ios/GDBinding/GDHttpRequest.g.cs obj/Debug/ios/GDBinding/NSURLCache.g.cs obj/Debug/ios/GDBinding/GDURLLoadingSystem.g.cs obj/Debug/ios/GDBinding/GDCacheController.g.cs obj/Debug/ios/GDBinding/GDPushConnectionDelegate.g.cs obj/Debug/ios/GDBinding/GDPushConnection.g.cs obj/Debug/ios/GDBinding/GDPushChannelDelegate.g.cs obj/Debug/ios/GDBinding/GDPushChannel.g.cs obj/Debug/ios/GDBinding/GDSecureDocs.g.cs obj/Debug/ios/GDBinding/GDAppEvent.g.cs obj/Debug/ios/GDBinding/GDiOSDelegate.g.cs obj/Debug/ios/GDBinding/GDiOS.g.cs obj/Debug/ios/GDBinding/NSMutableURLRequest.g.cs /target:library /unsafe+ /define:DEBUG /reference:/Developer/MonoTouch/usr/lib/mono/2.1/System.dll /reference:/Developer/MonoTouch/usr/lib/mono/2.1/monotouch.dll /reference:../../../Desktop/GDExtended/GDBinding.dll /reference:/Developer/MonoTouch/usr/lib/mono/2.1/System.Core.dll /reference:/Developer/MonoTouch/usr/lib/mono/2.1/mscorlib.dll /warn:4 
obj/Debug/ios/GDBinding/GDSocket.g.cs(273,53): warning CS0436: The type `GDBinding.GDSocketDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDHttpRequest.g.cs(541,58): warning CS0436: The type `GDBinding.GDHttpRequestDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDPushConnection.g.cs(180,61): warning CS0436: The type `GDBinding.GDPushConnectionDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDPushChannel.g.cs(175,58): warning CS0436: The type `GDBinding.GDPushChannelDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDiOS.g.cs(393,50): warning CS0436: The type `GDBinding.GDiOSDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/ObjCRuntime/Messaging.g.cs(53,134): warning CS0436: The type `GDBinding.GDFileStat' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDFileSystem.g.cs(159,31): warning CS0436: The type `GDBinding.GDCReadStream' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDFileSystem.g.cs(181,31): warning CS0436: The type `GDBinding.GDCWriteStream' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDDirectByteBuffer.g.cs(139,46): warning CS0108: `GDBinding.GDDirectByteBuffer.Init' hides inherited member `MonoTouch.Foundation.NSObject.Init()'. Use the new keyword if hiding was intended 
/Developer/MonoTouch/usr/lib/mono/2.1/monotouch.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDSocket.g.cs(177,32): warning CS0436: The type `GDBinding.GDDirectByteBuffer' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDHttpRequest.g.cs(377,46): warning CS0108: `GDBinding.GDHttpRequest.Init' hides inherited member `MonoTouch.Foundation.NSObject.Init()'. Use the new keyword if hiding was intended 
/Developer/MonoTouch/usr/lib/mono/2.1/monotouch.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDHttpRequest.g.cs(449,32): warning CS0436: The type `GDBinding.GDHttpRequest_state_t' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/NSURLCache.g.cs(79,57): warning CS0436: The type `GDBinding.NSURLCache' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDPushConnection.g.cs(84,31): warning CS0436: The type `GDBinding.GDPushConnection' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDPushChannel.g.cs(148,46): warning CS0108: `GDBinding.GDPushChannel.Init' hides inherited member `MonoTouch.Foundation.NSObject.Init()'. Use the new keyword if hiding was intended 
/Developer/MonoTouch/usr/lib/mono/2.1/monotouch.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDSecureDocs.g.cs(101,85): warning CS0436: The type `GDBinding.SendFileSuccessBlock' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDAppEvent.g.cs(82,32): warning CS0436: The type `GDBinding.GDAppResultCode' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDAppEvent.g.cs(102,32): warning CS0436: The type `GDBinding.GDAppEventType' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDiOSDelegate.g.cs(76,51): warning CS0436: The type `GDBinding.GDAppEvent' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDiOS.g.cs(139,36): warning CS0465: Introducing `Finalize' method can interfere with destructor invocation. Did you intend to declare a destructor? 
obj/Debug/ios/GDBinding/GDiOS.g.cs(163,31): warning CS0436: The type `GDBinding.GDiOS' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/GDiOS.g.cs(281,94): warning CS0436: The type `GDBinding.GDUIColorTheme' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/GDBinding/NSMutableURLRequest.g.cs(83,67): warning CS0436: The type `GDBinding.NSMutableURLRequest' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 
obj/Debug/ios/ObjCRuntime/Messaging.g.cs(44,84): warning CS0436: The type `GDBinding.Messaging' conflicts with the imported type of same name'. Ignoring the imported type definition 
/Users/thabetkacem/Desktop/GDExtended/GDBinding.dll (Location of the symbol related to previous warning) 

Target DeployOutputFiles: 
    Copying file from '/Users/thabetkacem/Projects/GDBinding/GDBinding/obj/Debug/GDBinding.dll.mdb' to '/Users/thabetkacem/Projects/GDBinding/GDBinding/bin/Debug/GDBinding.dll.mdb' 
    Copying file from '/Users/thabetkacem/Projects/GDBinding/GDBinding/obj/Debug/GDBinding.dll' to '/Users/thabetkacem/Projects/GDBinding/GDBinding/bin/Debug/GDBinding.dll' 
Done building project "/Users/thabetkacem/Projects/GDBinding/GDBinding/GDBinding.csproj". 

Build succeeded. 

Warnings: 

/Users/thabetkacem/Projects/GDBinding/GDBinding/GDBinding.csproj (Build) -> /Library/Frameworks/Mono.framework/External/xbuild/Xamarin/Xamarin.ObjcBinding.CSharp.targets 
(GenerateBindings target) -> 

GDBinding.cs(642,22): warning CS0465: Introducing `Finalize' method can interfere with destructor invocation. Did you intend to declare a destructor? 

/Users/thabetkacem/Projects/GDBinding/GDBinding/GDBinding.csproj (Build) -> 
/Library/Frameworks/Mono.framework/Versions/2.10.9/lib/mono/4.0/Microsoft.CSharp.Targets (CoreCompile target) -> 

obj/Debug/ios/GDBinding/GDSocket.g.cs(273,53): warning CS0436: The type `GDBinding.GDSocketDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDHttpRequest.g.cs(541,58): warning CS0436: The type `GDBinding.GDHttpRequestDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDPushConnection.g.cs(180,61): warning CS0436: The type `GDBinding.GDPushConnectionDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDPushChannel.g.cs(175,58): warning CS0436: The type `GDBinding.GDPushChannelDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDiOS.g.cs(393,50): warning CS0436: The type `GDBinding.GDiOSDelegate' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/ObjCRuntime/Messaging.g.cs(53,134): warning CS0436: The type `GDBinding.GDFileStat' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDFileSystem.g.cs(159,31): warning CS0436: The type `GDBinding.GDCReadStream' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDFileSystem.g.cs(181,31): warning CS0436: The type `GDBinding.GDCWriteStream' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDDirectByteBuffer.g.cs(139,46): warning CS0108: `GDBinding.GDDirectByteBuffer.Init' hides inherited member `MonoTouch.Foundation.NSObject.Init()'. Use the new keyword if hiding was intended 
obj/Debug/ios/GDBinding/GDSocket.g.cs(177,32): warning CS0436: The type `GDBinding.GDDirectByteBuffer' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDHttpRequest.g.cs(377,46): warning CS0108: `GDBinding.GDHttpRequest.Init' hides inherited member `MonoTouch.Foundation.NSObject.Init()'. Use the new keyword if hiding was intended 
obj/Debug/ios/GDBinding/GDHttpRequest.g.cs(449,32): warning CS0436: The type `GDBinding.GDHttpRequest_state_t' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/NSURLCache.g.cs(79,57): warning CS0436: The type `GDBinding.NSURLCache' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDPushConnection.g.cs(84,31): warning CS0436: The type `GDBinding.GDPushConnection' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDPushChannel.g.cs(148,46): warning CS0108: `GDBinding.GDPushChannel.Init' hides inherited member `MonoTouch.Foundation.NSObject.Init()'. Use the new keyword if hiding was intended 
obj/Debug/ios/GDBinding/GDSecureDocs.g.cs(101,85): warning CS0436: The type `GDBinding.SendFileSuccessBlock' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDAppEvent.g.cs(82,32): warning CS0436: The type `GDBinding.GDAppResultCode' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDAppEvent.g.cs(102,32): warning CS0436: The type `GDBinding.GDAppEventType' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDiOSDelegate.g.cs(76,51): warning CS0436: The type `GDBinding.GDAppEvent' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDiOS.g.cs(139,36): warning CS0465: Introducing `Finalize' method can interfere with destructor invocation. Did you intend to declare a destructor? 
obj/Debug/ios/GDBinding/GDiOS.g.cs(163,31): warning CS0436: The type `GDBinding.GDiOS' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/GDiOS.g.cs(281,94): warning CS0436: The type `GDBinding.GDUIColorTheme' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/GDBinding/NSMutableURLRequest.g.cs(83,67): warning CS0436: The type `GDBinding.NSMutableURLRequest' conflicts with the imported type of same name'. Ignoring the imported type definition 
obj/Debug/ios/ObjCRuntime/Messaging.g.cs(44,84): warning CS0436: The type `GDBinding.Messaging' conflicts with the imported type of same name'. Ignoring the imported type definition 

25 Warning(s) 
0 Error(s) 

Time Elapsed 00:00:05.0845450 

---------------------- Done ---------------------- 

Build: 0 errors, 25 warnings 


Any help would be greatly appreciated. 

Answer 1

如果你不链接可能出现这种情况，手动或（更好）与[LinkWith]属性，本地库（即您绑定）与您的应用程序。

在这种情况下，选择的消息将不会到达本地代码，并将返回null（它会显示手柄（实例或类）是0x0。

为了证实这一点看看你构建输出（内MonoDevelop的），看看你的libX.a被链接到你的应用程序。

也可以尝试这种在模拟器（I386）和设备（ARMv6及/或ARMv7的），因为它可能是你的本地库架构不可用（在你的.a）。