在 Xcode 5.0.2 中,我创建了一个 iPhone 应用程序(完整的应用程序 code is on GitHub,请运行 pod install
一次 - 对于 SDWebImage
),它显示社交网络列表(Facebook、Google+ 等),然后 - 在另一个 View 中 - 一个显示 OAuth2 网页的 UIWebView
,然后是带有用户头像和详细信息(名字,姓氏等)的第三个 View .):
(此处the fullscreen screenshot of the storyboard如上所示)
在最后一个 View 中显示用户头像和详细信息之前,我将用户数据保存到NSUserDefaults
。
我的问题是:当用户下次启动应用程序并且 NSUserDefaults
中已经有用户数据时 - 我如何跳过前 2 个 View 并显示 (没有任何动画)最后一次查看这些用户详细信息?
我已将以下代码放入 AppDelegate.m :
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *key = [defaults objectForKey:@"key"];
User *user = [User loadForKey:key];
if (user) {
UINavigationController *nc = (UINavigationController*)self.window.rootViewController;
// XXX how to load the last view here? XXX
}
return YES;
}
并且可以看到,用户数据正在正常加载,但我不明白如何跳转到最后一个 View (尤其是因为大部分 UI 都在 Storyboard中定义)?
更新:我尝试按照 Tommy Alexander 的建议(谢谢!)在 AppDelegate.m 中使用以下代码(并且还为最后一个 View 分配了 Details
StoryboardID):
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *key = [defaults objectForKey:@"key"];
User *user = [User loadForKey:key];
if (user) {
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
UIViewController *uvc = [storyboard instantiateViewControllerWithIdentifier:@"Details"];
NSLog(@"XXX uvc=%@ user=%@", uvc, user);
[self.window.rootViewController presentViewController:uvc animated:YES completion:nil];
}
return YES;
}
虽然最后一个 View (带有用户头像和详细信息的 UserViewController)似乎可以正常实例化,但我收到以下警告并且应用程序没有跳转到最后一个 View :
MyAuth[3917:70b] XXX uvc=<UserViewController: 0x8acbac0> user=
VK
59751265
Alexander
Farber
1945522
http://cs319319.vk.me/v319319265/b7df/TnyKeffL_mU.jpg
0
MyAuth[3917:70b] Warning: Attempt to present <UserViewController: 0x8acbac0> on <UINavigationController: 0x8bb3a30> whose view is not in the window hierarchy!
更新 2: 当我将上面的代码移动到第一个 View 的 viewDidLoad
时(MasterViewController.m,用户可以在其中选择社交网络),然后我收到另一个警告:
MyAuth[1358:70b] XXX uvc=<UserViewController: 0x8a97430> user=
FB
597287941
Alexander
Farber
Bochum, Germany
http://graph.facebook.com/597287941/picture?type=large
0
MyAuth[1358:70b] Unbalanced calls to begin/end appearance transitions for <UINavigationController: 0x8a893e0>.
更新 3:感谢您提供宝贵的答案!我最终使用了 Leonty Deriglazov 的建议:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
UIViewController *vc1 = [storyboard instantiateViewControllerWithIdentifier:@"Master"];
//UIViewController *vc2 = [storyboard instantiateViewControllerWithIdentifier:@"Login"];
UIViewController *vc3 = [storyboard instantiateViewControllerWithIdentifier:@"User"];
User *user = [User load];
NSArray *controllers = (user ? @[vc1, vc3] : @[vc1]);
UINavigationController *nc = (UINavigationController *)self.window.rootViewController;
[nc setViewControllers:controllers];
return YES;
}
最佳答案
简而言之,最直接的解决方案是使用-[UINavigationController setViewControllers:animated:]
。
您需要执行以下操作才能实现您想要的:
- 为所有 Controller 分配 Storyboard ID,
- 从 Storyboard实例化所有三个 View Controller (这是轻量级的,只要您不在 Controller 的构造函数中进行大部分初始化工作)
- 按照 Storyboard中的顺序将它们放入数组中,
- 使用数组作为第一个参数调用
-[UINavigationController setViewControllers:]
。
就是这样。 -[AppDelegate application:didFinishLaunchingWithOptions:]
中的代码可能如下所示(当然在检查您的跳过条件之后):
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
UIViewController *vc1 = [storyboard instantiateViewControllerWithIdentifier:@"MyAuth"]; //if you assigned this ID is storyboard
UIViewController *vc2 = [storyboard instantiateViewControllerWithIdentifier:@"Login"]; //if you assigned this ID is storyboard
UIViewController *vc3 = [storyboard instantiateViewControllerWithIdentifier:@"Details"];
NSArray *controllers = @[vc1, vc2, vc3];
UINavigationController *navController = (UINavigationController *)self.window.rootViewController;
[navController setViewControllers:controllers];
如果您只将其粘贴到 -[AppDelegate application:didFinishLaunchingWithOptions:]
,您会发现它会立即生效。
关于ios - 使用导航 Controller 时如何跳过 2 个 View ,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/21537773/