如何检查iPhone应用程序启动的时间？

Question

我目前正在开发一个iOS应用程序。我需要比较在iPhone和/或iPad上启动的时间。有人可以提醒吗？

Answer 1

请注意当前时间main()和-application:didFinishLaunchingWithOptions:，然后计算差异。例如：

的main.m：

// main.m 

NSDate *startupDate; 

int main(int argc, char **argv) 
{ 
    NSAutoreleasePool *pool = [NSAutoreleasePool new]; 
    startupDate = [[NSDate alloc] init]; 
    int exitCode = UIApplicationMain(argc, argv, NULL, @"AppDelegate"); 
    [startupDate release]; 
    [pool drain]; 
    return exitCode; 
} 

// etc. 

AppDelegate.m：

// AppDelegate.m 

extern NSDate *startupDate; 

- (BOOL)application:(UIApplication *)app didFinishLaunchingWithOptions:(NSDictionary *)opts 
{ 
    NSDate *launchFinishedDate = [[NSDate alloc] init]; 
    NSTimeInterval launchTimeInSeconds = [launchFinishedDate timeIntervalSinceDate:startupDate]; 
    [launchFinishedDate release]; 

    // launchTimeInSeconds will contain the launch time in seconds (floating point). 
    // create UI setup etc. as usual 
} 

Answer 2

你可以使用工具（包含在Xcode）与时间探查器监视您的应用程序的启动。