无法隐藏以编程方式创建的UIButton？

Question

LoginController尝试简单登录尝试 - 如果其成功，则调用setEmail,leftcontroller。

所有我需要做的，当setEmail被调用是隐藏btnLogin并显示buttonUser并没有什么我尝试工作。 NSLog被调用，EventsController加载使setEmail正在工作 - 它不会隐藏和显示按钮。

leftcontroller.h：

@interface LeftController : UIViewController <UIApplicationDelegate> 
{ 
    IBOutlet UIButton *btnLogin; 
    IBOutlet UIButton *buttonUser; 
    NSString *setEmail; 
} 
@property (nonatomic,strong) IBOutlet UIButton *btnLogin; 
@property (nonatomic,strong) IBOutlet UIButton *buttonUser; 

@property(nonatomic,strong) UITableView *tableView; 
@property(nonatomic) NSString *Email; 

//-(void) setEmail : (NSString *) Email; 

@end 

leftcontroller.m：

- (void) setEmail : (NSString *) Email{ 
    [buttonUser setTitle:Email forState:UIControlStateNormal]; 
    //btnLogin.hidden = YES; 
    //buttonUser.hidden = NO; 
    [btnLogin setHidden:YES]; 
    [buttonUser setHidden:NO]; 

    NSLog(@"Set Email Called"); 
    NSLog(@"email: %@", Email); 

    DDMenuController *menuController = (DDMenuController*)((AppDelegate*)[[UIApplication sharedApplication] delegate]).menuController; 
    EventsViewController *controller = [[EventsViewController alloc] init]; 
    UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:controller]; 

     [menuController setRootController:navController animated:YES]; 
} 

-(void)viewDidLoad { 
    [super viewDidLoad]; 

    self.view.backgroundColor = HEXCOLOR(0x000000); 

    btnLogin = [UIButton buttonWithType:UIButtonTypeRoundedRect]; 
    btnLogin.frame = CGRectMake(0, 0, 180.f, 48); 
    [btnLogin setTitle:@"Login" forState:UIControlStateNormal]; 
    [btnLogin addTarget:self action:@selector(LoginPressed) 
     forControlEvents:UIControlEventTouchUpInside]; 
    btnLogin.tag=1; 

    btnLogin.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft; 
    [btnLogin setTitleColor: [UIColor whiteColor] forState:UIControlStateNormal]; 
    btnLogin.contentEdgeInsets = UIEdgeInsetsMake(0, 10, 0, 0); 

    UIImage *btnImage = [UIImage imageNamed:@"nav_top.png"]; 
    [btnLogin setBackgroundImage:btnImage forState:UIControlStateNormal]; 
    [self.view addSubview:btnLogin]; 

    buttonUser = [UIButton buttonWithType:UIButtonTypeRoundedRect]; 
    buttonUser.frame = CGRectMake(0, 0, 180.f, 48); 
    //[buttonUser setTitle:_Email forState:UIControlStateNormal]; 
    [buttonUser addTarget:self action:@selector(EmailPressed) 
     forControlEvents:UIControlEventTouchUpInside]; 
    buttonUser.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft; 
    [buttonUser setTitleColor: [UIColor whiteColor] forState:UIControlStateNormal]; 
    buttonUser.contentEdgeInsets = UIEdgeInsetsMake(0, 10, 0, 0); 

    UIImage *btnImage1 = [UIImage imageNamed:@"nav_top.png"]; 
    [buttonUser setBackgroundImage:btnImage1 forState:UIControlStateNormal]; 
    [self.view addSubview:buttonUser]; 
    buttonUser.hidden = YES; 
} 

Answer 1

此行是犯罪嫌疑人：

btnLogin = [UIButton buttonWithType:UIButtonTypeRoundedRect]; 
// ... 
[self.view addSubview:btnLogin]; 

如果要创建btnLogin并将其添加到self.view自己，在代码中，然后为什么是这样的n outlet？

@property (nonatomic,strong) IBOutlet UIButton *btnLogin; 

一个出口的东西，已经存在，并且在你的笔尖是实例。因此，在我看来，你可能有两个对象，其中一个对象将你的引用擦除掉。而另一个按钮也一样。

Answer 2

你没有设置你的财产，替换：

btnLogin = [UIButton buttonWithType:UIButtonTypeRoundedRect]; 

有：

self.btnLogin = [UIButton buttonWithType:UIButtonTypeRoundedRect]; 

，并定义像你的财产：

@property (nonatomic,strong) UIButton *btnLogin; 

执行相同的buttonUser。

Answer 3

设置你的按钮的hidden后，您立即说

[menuController setRootController:navController animated:YES];} 

这表明，你正在改变接口。但是如果你正在改变界面，你真的可以告诉你的按钮是否改变了吗？我不知道你在这里做什么，但也许你的按钮不再在界面中。也许你在界面上看到的是不同的按钮组。