Objective c 从RootViewController调用函数

如何从

FirstViewController

调用

RootViewController

函数？ 我将Xcode 4.6与情节提要一起使用

---

RootViewController.m：

-(void)openMenu
{
    ...
}

FirstViewController：

- (IBAction)btnMenu:(id)sender {
    RootViewController *root = [[RootViewController alloc] init];
    [root openMenu]; // No visible @interface for 'RootViewController' declares the selector 'openMenu'
}

---

您必须在标题

RootViewController.h

中声明该方法。范例

- (void)openMenu;

---

您必须在标题

RootViewController.h

中声明该方法。范例

- (void)openMenu;

---

对于这样的事情，一种常见的做法是使用委托。您的

FirstViewController

将有一个委托，然后您的

RootViewController

将为实例设置委托，并接收事件的信息

FirstViewController.h

@protocol FirstViewDelegate;

@interface FirstViewController : UIViewController

@property (strong) id<FirstViewDelegate> delegate;

@end

@protocol FirstViewDelegate <NSObject>

- (void)openMenu;

@end

#import "FirstViewController.h"

@interface RootViewController : UIViewController
<
FirstViewDelegate
>

MainViewController.h

@protocol FirstViewDelegate;

@interface FirstViewController : UIViewController

@property (strong) id<FirstViewDelegate> delegate;

@end

@protocol FirstViewDelegate <NSObject>

- (void)openMenu;

@end

#import "FirstViewController.h"

@interface RootViewController : UIViewController
<
FirstViewDelegate
>

---

对于这样的事情，一种常见的做法是使用委托。您的

FirstViewController

将有一个委托，然后您的

RootViewController

将为实例设置委托，并接收事件的信息

FirstViewController.h

@protocol FirstViewDelegate;

@interface FirstViewController : UIViewController

@property (strong) id<FirstViewDelegate> delegate;

@end

@protocol FirstViewDelegate <NSObject>

- (void)openMenu;

@end

#import "FirstViewController.h"

@interface RootViewController : UIViewController
<
FirstViewDelegate
>

MainViewController.h

@protocol FirstViewDelegate;

@interface FirstViewController : UIViewController

@property (strong) id<FirstViewDelegate> delegate;

@end

@protocol FirstViewDelegate <NSObject>

- (void)openMenu;

@end

#import "FirstViewController.h"

@interface RootViewController : UIViewController
<
FirstViewDelegate
>

---

为什么要从其他控制器调用与UI相关的方法？为什么要从其他控制器调用与UI相关的方法？