Question

我正在实现一个应用程序功能，其中有6-7个屏幕流入。用户可以在任何屏幕上离开/关闭流程。

但是，当用户再次申请应用程序时，他们应该跳到他离开的最后一个屏幕，而且他还可以返回到先前的屏幕。

例如：我开始申请申请，直到第4个屏幕并关闭为止。再次申请，我必须直接跳到第4个屏幕，并且还必须从堆栈中返回第3个-> 2nd->第一个屏幕。

当前代码：

Storyboard中1-7的屏幕的序列识别为“ screen1”，“ screen1” ...“ screen7”

从HomeScreen.m

-(void)toPersonalApplication {

    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Personal" bundle:nil];
    ScreenOne *screenOne = [storyboard instantiateViewControllerWithIdentifier:@"screenOne"];
    UINavigationController* nav = [[UINavigationController alloc] initWithRootViewController:screenOne];
    [self presentViewController:nav animated:YES completion:nil];
}

检查用户是否已经启动了申请流程：

在ScreenOne.m

   - (IBAction)btnNextClick:(id)sender {

        if (doneProcessTill == 4) {

        // Should be execute something like this here
        // [self performSegueWithIdentifier:@"screen2" sender:self];
        // [self performSegueWithIdentifier:@"screen3" sender:self];
        // [self performSegueWithIdentifier:@"screen4" sender:self];
      }

    }

感谢您的建议！谢谢

Answer 1

如我的评论所述，解决方案可能如下所示：

- (void)toPersonalApplication {
    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Personal" bundle:nil];

    NSMutableArray *viewControllers = [NSMutableArray array];
    for (NSInteger i = 1; i <= doneProcessTill; ++i) {
        UIViewController *viewController = [storyboard instantiateViewControllerWithIdentifier:[NSString stringWithFormat:@"screen%ld", (long)i]];
        [viewControllers addObject:viewController];
    }

    UINavigationController *navigationController = [UINavigationController new];
    navigationController.viewControllers = viewControllers;

    [self presentViewController:navigationController animated:YES completion:nil];
}

Answer 2

在这种情况下，最好保存您的视图控制器，然后在您想回到原来的位置时再次显示它们。您随时可以使用navigationController.viewControllers获取当前的视图控制器。要设置整个堆栈，您需要做的就是在导航控制器上调用setViewControllers。

您可以覆盖导航控制器以存储控制器数组。或者，您也可以静态保存它。哪种情况比较方便。

静态图片如下：

static NSArray<UIViewController *> *__preservedControllers = nil;

@implementation ViewController

- (void)onClose {
    __preservedControllers = self.navigationController.viewControllers;
    // Insert logic to close the whole procedure
}

- (void)reopenSavedStack {
    if(__preservedControllers) {
        [self.navigationController setViewControllers:__preservedControllers animated:YES];
        __preservedControllers = nil;
    }
}

使用子类化导航控制器，它看起来可能会更好：

@interface MyNavigationController : UINavigationController

@property (nonatomic, strong) NSArray<UIViewController *> *savedStack;

@end

@implementation MyNavigationController

- (void)saveStack {
    self.savedStack = self.viewControllers;
}

- (void)restoreStack:(BOOL)animated {
    if(self.savedStack.count > 0) {
        [self setViewControllers:self.savedStack animated:YES];
        self.savedStack = nil;
    }
}

@end

但是您确实需要进行类型转换：

- (void)onClose {
    [(MyNavigationController *)self.navigationController saveStack];
    // Insert logic to close the whole procedure
}

- (void)reopenSavedStack {
    [(MyNavigationController *)self.navigationController restoreStack:YES];
}

ObjectiveC：在导航控制器中添加/执行多个segue

2 个答案: