navigationController'中的调用方法；从堆栈中的第三个ViewController中删除rootViewController-iOS

我的

NavigationController

层次结构如下：

vc1->vc2->vc3

我想在撤销vc3时从vc3调用一个vc1方法

我试图实现委托，但由于vc1没有vc3对象，因此无法工作

（vc3是在从vc2开始的

segue

时创建的）

我尝试实现委托，但由于vc1没有vc3 对象，它不起作用

是的，但当您在v2的生命周期范围内创建v3时，您可以访问v1和v3（我想，您可以在

-（void）prepareForSegue:（UIStoryboardSegue*）中将v1和v3链接在一起。
更新：尝试使用self.navigationController.viewControllers[0]检索vc1。
尝试以下代码：
创建三个视图控制器
视图控制器1
视图控制器2
视图控制器3

//视图控制器1.h

    #import <UIKit/UIKit.h>
    #import "ViewController2.h"
    #import "ViewController3.h"


    @interface ViewController1 : UIViewController <callDelegate>

    @end

//ViewController2.h

#import <UIKit/UIKit.h>
#import "ViewController3.h"


@interface ViewController2 : UIViewController 
@property(nonatomic,strong) UIViewController *myView;
@end

//ViewController3.h

#import <UIKit/UIKit.h>
@protocol callDelegate <NSObject>

-(void)delegateCalled;

@end
@interface ViewController3 : UIViewController 
@property(nonatomic,weak)id<callDelegate>mydelegate;

@end

我基本上想这样做：
vc3.delegate=self//vc1
，但这不能在vc1类中完成，因为没有vc3对象。按照你说的，我在vc2的
prepareForSegue
中尝试了这个方法：
vc2.delegate=self.parentViewController但运气不好，vc1中未调用still delegate方法：（由于self.parentViewController为nil，您未将它们链接在一起。请尝试使用self.navigationController.ViewController[0]要检索vc1。另外，您能告诉我为什么
self.parentViewController
为零吗？vc1不是vc2的父级吗？：S
parentViewController
是指实际的
navigationController
而不是其中的
ViewController
？当然，请先看。父级视图控制器涉及到父级子级VC hierarchies，不是先前的继任者。让我们来回答。答案已经提供。请阅读整个帖子（问题和答案（如果有的话），然后添加你的答案。谢谢！
#import "ViewController2.h"
#import "ViewController3.h"

@interface ViewController2 ()

@end

@implementation ViewController2 

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

//    ViewController3 *v3=[[ViewController3 alloc]init];
//   self.myView.mydelegate=self;
    [self.navigationController pushViewController:self.myView animated:YES];


    UILabel *lbl=[[UILabel alloc]initWithFrame:CGRectMake(100, 100, 100, 100)];
    [self.view addSubview:lbl];
    self.view.backgroundColor=[UIColor whiteColor];
    lbl.backgroundColor=[UIColor redColor];

    lbl.text=@"V2";

}

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

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end

#import <UIKit/UIKit.h>
@protocol callDelegate <NSObject>

-(void)delegateCalled;

@end
@interface ViewController3 : UIViewController 
@property(nonatomic,weak)id<callDelegate>mydelegate;

@end

#import "ViewController3.h"

@interface ViewController3 ()

@end

@implementation ViewController3

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    UIButton *lbl=[[UIButton alloc]initWithFrame:CGRectMake(100, 100, 100, 100)];
    [self.view addSubview:lbl];
    self.view.backgroundColor=[UIColor whiteColor];
lbl.backgroundColor=[UIColor redColor];
    [lbl setTitle:@"v3" forState:UIControlStateNormal];
    [lbl addTarget:self action:@selector(buttonClick) forControlEvents:UIControlEventTouchUpInside];

}
-(void)viewDidDisappear:(BOOL)animated{
    [self.mydelegate delegateCalled];

}

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

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end