主文件中的标准参数

Question

主文件中的标准参数是什么.我想我在主文件中设置了错误的标准参数,需要更改它们.我认为问题是UIApplicationMain参数中的nil和nil.

这是我的代码:

#import <UIKit/UIKit.h>

int main(int argc, char *argv[])
{
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    int retVal = UIApplicationMain(argc, argv, nil, nil);
    [pool release];
    return retVal;
}

错误代码:

Attaching to process 1420.
2011-09-02 14:33:04.440 HypnoTime[1420:207] *** Assertion failure in           UIApplicationMain(), /SourceCache/UIKit_Sim/UIKit-1448.89/UIApplication.m:1359
2011-09-02 14:33:04.588 HypnoTime[1420:207] *** Terminating app due to uncaught      exception 'NSInternalInconsistencyException', reason: 'Unable to instantiate the      UIApplication delegate instance. No class named AppDelegate is loaded.'
 *** Call stack at first throw:
 (
     0   CoreFoundation                      0x00dc15a9 __exceptionPreprocess + 185
     1   libobjc.A.dylib                     0x00f15313 objc_exception_throw + 44
     2   CoreFoundation                      0x00d79ef8 +[NSException      raise:format:arguments:] + 136
     3   Foundation                          0x00816341 -[NSAssertionHandler handleFailureInFunction:file:lineNumber:description:] + 101
     4   UIKit                               0x00021bcd UIApplicationMain + 962
     5   HypnoTime                           0x000027cf main + 127
     6   HypnoTime                           0x00002745 start + 53
     7   ???                                 0x00000001 0x0 + 1
)
terminate called after throwing an instance of 'NSException'
Current language:  auto; currently objective-c
(gdb) 

Answer 1

UIApplicationMain的最后一个参数是您的UIApplicationDelegate子类的名称.如果您以编程方式创建应用程序,而不使用任何nib文件,则需要它.

int retval = UIApplicationMain(argc, argv, nil, NSStringFromClass([YourAppDelegate class]));

您需要以#import "YourAppDelegate.h"这种方式工作,或者您可以像Voloda2建议的那样对该名称进行硬编码.

使用这种方式的好处是,如果您更改您的app委托类名称,您将立即收到编译器警告,而如果它是硬编码的,它将构建并运行而不会发出警告,但会崩溃.