小编Leo*_*Leo的帖子

我正从AppDelegate班上查看我ParentEndViewController目前是否是可见课程.

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard_iPhone" bundle: nil];  
ParentEndViewController *parent = [storyboard instantiateViewControllerWithIdentifier:@"ParentEndViewController"];
 if (parent.isViewLoaded && parent.view.window){
         UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:displayName
                                                            message:body
                                                           delegate:nil
                                                  cancelButtonTitle:@"Ok"
                                                  otherButtonTitles:nil];
        [alertView show];
        NSLog(@"current view is parent!");
    }
    else{
        NSLog(@"current view is not parent!");
    }

它正在打印current view is not parent!".但我确信我的应用程序上运行的当前视图是ParentEndViewController,它应该打印current view is parent!.

问题出在哪儿？

我在课堂上有7种方法.当我收到一条特定的消息时,我必须从这7种方法中随机调用一种方法.我的示例代码是:

-(void)poemAbcd{

    UIImage *image = [UIImage imageNamed: @"abcd_bg.png"];
    [backgroundImage setImage:image];

    [self changeMumuPosition:80 with:220];
}

-(void)poemHumptyDumpty{

    UIImage *image = [UIImage imageNamed: @"humpty_dumpty.png"];
    [backgroundImage setImage:image];

    [self changeMumuPosition:80 with:170];
}

-(void)poemBlackship{

    UIImage *image = [UIImage imageNamed: @"black_sheep.png"];
    [backgroundImage setImage:image];

    [self changeMumuPosition:66 with:229];
}

-(void)poemRowRow{

    UIImage *image = [UIImage imageNamed: @"boat_bg.png"];
    [backgroundImage setImage:image];

    [self changeMumuPosition:144 with:211];
}

-(void)poemHappy{

    UIImage *image = [UIImage imageNamed: @"boat_bg.png"];
    [backgroundImage setImage:image];

    [self changeMumuPosition:144 with:211];
}

-(void)poemItsyBitsy{

    UIImage *image = [UIImage imageNamed: @"boat_bg.png"];
    [backgroundImage setImage:image];

    [self changeMumuPosition:144 with:211];
}

-(void)poemTwinkleTwinkle{ …