iOS一些常用的小知识点

  //获取全局的Delegate对象，这样我们可以调用这个对象里的方法和变量

    [[UIApplication sharedApplication] delegate];

    //获得程序的主Bundle

    NSBundle *bundle = [NSBundle mainBundle];

    /*

     在程序中播放声音

     1.添加AudioToolbox框架

     */

    NSString *path = [bundle pathForResource:@"soundFileName" ofType:@"wav"];

    SystemSoundID soundId;

    AudioServicesCreateSystemSoundID((__bridge CFURLRef)([NSURL URLWithString:path]), &soundId);

    AudioServicesPlayAlertSound(soundId);

    //捕捉程序关闭或者进入后台事件

    UIApplication *application = [UIApplication sharedApplication];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationWillResignActive:) name:UIApplicationWillResignActiveNotification object:application];

    

    

    

}

- (void)applicationWillResignActive:(NSNotification *)noti{

    

}

#pragma mark -- 获取截屏

- (UIImage *)getScreenShot{

    UIGraphicsBeginImageContext(self.view.bounds.size);

    [self.view.layer renderInContext:UIGraphicsGetCurrentContext()];

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return image;

}