NSArrayM replaceObjectAtIndex：withObject：object can not be nil'

Question

我有一个项目与this相同的菜单，但与子菜单相同的幻灯片动画。我创建了一个名为SecondMenu.xib的xib文件名。文件所有者是UIViewController并将其命名为SecondMenuController。如果您检查项目REFrosted（check the link），则有DEMOMenuViewController（UIViewController）。在方法didSelectRowAtIndexPath：中。我在我的代码中更改了它

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
{ 

    NSMutableArray *controllers = [[NSMutableArray alloc] init]; 
    for (unsigned i = 0; i < 1; i++) { 
     [controllers addObject:[NSNull null]]; 
    } 
    self.viewControllers = controllers; 
    SecondMenuController *controller = [self.viewControllers objectAtIndex:0]; 

    if ((NSNull *)controller == [NSNull null]) { 
     controller = [[SecondMenuController alloc] initWithNibName:@"SecondMenu" bundle:nil]; 
     [self.viewControllers replaceObjectAtIndex:0 withObject:controller]; 

    } 

    controller.view.frame = CGRectMake(-self.view.frame.size.width, 0,self.view.frame.size.width,self.view.frame.size.height); 

    [self.view addSubview:controller.view]; 


    [UIView animateWithDuration:0.5 delay:0.0 options:UIViewAnimationOptionCurveEaseInOut animations:^{ 
     controller.view.frame = CGRectMake(0, 0,self.view.frame.size.width,self.view.frame.size.height); 
    } completion:^(BOOL finished) { 
     NSLog(@"Done!"); 
    }]; 

    //[self hideMenu]; 

} 

当连接到子菜单（即SecondMenuController）时，该代码适用于我。在我的SecondMenuController中，我添加一个按钮（这将连接到DEMOHomeViewController，故事板标识符是homeController）。这里是我的按钮

- (IBAction)buttonConnect:(id)sender { 
    DEMONavigationController *navigationController = [self.storyboard instantiateViewControllerWithIdentifier:@"contentController"]; 

    DEMOHomeViewController *homeViewController = [self.storyboard instantiateViewControllerWithIdentifier:@"homeController"]; 
    navigationController.viewControllers = @[homeViewController]; 

    self.frostedViewController.contentViewController = navigationController; 
    [self.frostedViewController hideMenuViewController]; 
} 

的代码，我得到这个代码REFrosted之前，我把它改为我的代码在didSelectRowAtIndexPath方法：（正如我在第一个代码提到上文）。为什么我得到这个错误

'NSInvalidArgumentException', reason: '*** -[__NSArrayM replaceObjectAtIndex:withObject:]: object cannot be nil' 

我导入所有文件。正如我所了解的，当你导入连接到文件所有者的文件时。这意味着我可以控制每个方法或函数，当你将它实例化到我的SecondMenuController时（这只是基于我的经验，如果我错了，请纠正我，我只想知道系统是如何工作的）。请参阅我的代码。我在这里错过了什么吗？希望你建议我如何解决这个问题或解释为什么我得到这个错误。

DEMONavigationController *navigationController = [self.storyboard instantiateViewControllerWithIdentifier:@"contentController"]; 

    DEMOHomeViewController *homeViewController = [self.storyboard instantiateViewControllerWithIdentifier:@"homeController"]; 
    navigationController.viewControllers = @[homeViewController]; 

Answer 1

2天的搜索答案。我终于明白了。

为什么DEMOHomeViewController是零，当我点击按钮，因为SecondMenuController没有连接到DEMOHomeViewController，即使我将它实例化为SecondMenuController类的原因。我现在学习。这里的代码

我做的第一个代码。我添加此SecondMenuController.h

@property (nonatomic, weak) UIStoryboard * myself; 
@property (nonatomic, strong) REFrostedViewController * ref; 
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil myStoryBoard:(UIStoryboard *) xStoryBoard ref: (id) xRef; 

在SecondMenuController.m

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil myStoryBoard:(UIStoryboard *) xStoryBoard ref: (id) xRef 
{ 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 
    if (self) { 
     // Custom initialization 
     self.myself = xStoryBoard; 
     self.ref = xRef; 
    } 
    return self; 
} 

在我的按钮

DEMONavigationController *navigationController = [self.myself instantiateViewControllerWithIdentifier:@"contentController"]; 

DEMOSecondViewController *secondViewController = [self.myself instantiateViewControllerWithIdentifier:@"homeController"]; 

navigationController.viewControllers = @[secondViewController]; 


self.ref.frostedViewController.contentViewController = navigationController; 
    [self.ref.frostedViewController hideMenuViewController]; 

现在，它的工作。所有你需要做的就是调用DEMOMenuViewController的initWithNibName：方法。

Answer 2

控制台日志意味着你试图在NSArray中插入nil对象，这是不允许的。如果由于某种原因，您需要添加空物件使用(NSArray *)[NSNull null]。