Question

我正在尝试创建一个后退按钮以返回我的应用程序的主菜单，现在发生了什么，是，一旦我按下后退按钮，它会显示主菜单，但随后应用程序会在一秒后崩溃

我用于后退按钮的代码是;

- (void)backButtonPressed:(id)sender {
    [self.navigationController popViewControllerAnimated:YES];
}

来自AppDelegate.m文件

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
        self.viewController = [[[MenuViewController alloc] initWithNibName:@"MenuViewController_iPhone" bundle:nil] autorelease];
    } else {
        self.viewController = [[[MenuViewController alloc] initWithNibName:@"MenuViewController_iPad" bundle:nil] autorelease];
    }
    navigationController = [[myNavigationViewController alloc] initWithRootViewController:self.viewController];
    navigationController.navigationBarHidden = YES;
    self.window.rootViewController = navigationController;
    [self.window makeKeyAndVisible];
    return YES;
}

我看不出我错在哪里？它似乎调用了正确的屏幕，然后直接崩溃了？

编辑 - 这是MenuViewController.m文件;

#import "MenuViewController.h"
#import "MagicAppDelegate.h"
#import "MagicViewController.h"

@interface MenuViewController ()

@end

@implementation MenuViewController

- (void)viewDidLoad
{
    self.view.frame = [[UIScreen mainScreen] bounds];


    [super viewDidLoad];

  //  [self initLoad];

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.

}

-(IBAction)onStart:(id)sender
{
    MagicViewController* viewController;

    if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
        viewController = [[MagicViewController alloc] initWithNibName:@"MagicViewController_iPhone" bundle:[NSBundle mainBundle]];
    else
        viewController = [[MagicViewController alloc] initWithNibName:@"MagicViewController_iPad" bundle:[NSBundle mainBundle]];

    [self.navigationController pushViewController:viewController animated:YES];
    [viewController release];
}

- (void)dealloc {

    [super dealloc];
}

@end

Answer 1

请使用下面的代码，你想去mainmenuview控制器吗？

 [self.navigationController popToRootViewControllerAnimated:YES];

Answer 2

实际上，我并不理解您的代码：在navigationController = [[myNavigationViewController alloc] initWithRootViewController:self.viewController];语句中，您发送的alloc内容似乎是类{的实例 {1}}，但alloc是类方法。因此我假设myNavigationViewController是UINavigationController的子类（但是应该以大写字母开头）。
然后，返回的新实例直接分配给变量UINavigationController，即不使用setter方法。因此不保留。如果你的语句返回一个autorelease对象，它将在程序返回主事件循环后立即释放因此，尝试使用setter方法，即navigationController

应用程序崩溃使用popViewControllerAnimated：YES

2 个答案: