从弹出窗口类调用委托方法

我是新来的Objective C，我无法让委托在我的代码中工作。从弹出窗口类调用委托方法

我有一个名为cViewController的类，在这个类中有一个UIWebView来获取网页和它上面的一个按钮，它调用一个名为prodMenu的弹出类。我遇到的麻烦是，从prodMenu类调用网页并将其显示在父UIWebView上的功能不起作用。

cViewController.h

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

@interface cViewController : UIViewController <prodMenuDelegate>{ 
    UIPopoverController *cpopover; 
    IBOutlet UIWebView *webImageDisplay; 
} 
@property (nonatomic, retain) UIWebView *webImageDisplay; 
@property (nonatomic, retain) UIPopoverController *cpopover; 
- (IBAction)cPopoverTapped:(id)sender; 
- (void) fetchWebsite:(NSString *)website; //This is the delegate method I'm trying to call in the popover class. 
@end

cViewController.m

- (IBAction)cPopoverTapped:(id)sender { 
    prodMenu *tp = [[prodMenu alloc] init]; 
    cpopover = [[UIPopoverController alloc] initWithContentViewController:tp]; 
    [tp release]; 
    CGRect rect = CGRectMake(40, 0, 50, 50); 
    cpopover.popoverContentSize = CGSizeMake(250, 225); 
    [cpopover presentPopoverFromRect:rect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES]; 
} 

- (void)fetchWebsite:(NSString*)website{ //This function is called by prodMenu class 
    NSLog(@"address: %@", website); 
    NSString *urlAddress = website; 
    NSURL *url = [NSURL URLWithString:urlAddress]; 
    NSURLRequest *requestObj = [NSURLRequest requestWithURL:url]; 
    [webImageDisplay loadRequest:requestObj]; 
    [webImageDisplay release]; 
} 

- (void)viewDidLoad { 
    [self fetchWebsite:@"http://www.yahoo.com"]; 
    [super viewDidLoad]; 
}

prodMenu.h

#import <UIKit/UIKit.h> 
@protocol prodMenuDelegate; 

@interface prodMenu : UIViewController{ 
    <prodMenuDelegate> delegate; 
} 
- (IBAction)radBtn:(id)sender; //This is the IBAction that calls the fetchWebsite function 
@property (nonatomic, assign) id <prodMenuDelegate> delegate; 
@end 

@protocol prodMenuDelegate 
- (void)fetchWebsite:(NSString *)website; 
@end

prodMenu.m

#import "prodMenu.h" 
#import "cViewController.h" 

@implementation prodMenu 
@synthesize delegate; 

- (IBAction)radBtn:(id)sender{ 
    [delegate fetchWebsite:@"http://www.google.com"]; //Here is the call to the method 
}

我失去了一些东西在这里调用委托方法？没有任何错误或警告。我想要做的就是当用户在弹出视图上按下按钮时，下面的父类会更改网页。提前致谢。

来源

2011-03-08 Ray Y

prodMenu的实例在哪里？这就是将cViewController实例分配给“委托”属性的地方。 – 2011-03-08 15:11:10

对不起，添加了prodMenu的实例 – 2011-03-08 15:37:42

只是一个快速的想法。您是否试过宣布这样的代理协议

@protocol prodMenuDelegate <NSObject> 
    ... 
@end

？我忽略了< NSObject>时经常遇到麻烦。此外，我觉得有一个“身份证”在

@interface prodMenu : UIViewController{ 
    <prodMenuDelegate> delegate; 
}

编辑丢失：另外，在代码中你贴我没有看到你实际分配prodMenu的委托。

来源

2011-03-08 16:18:33 hennes

非常感谢，我真的错过了prodMenu的委托任务。我只需要一行“tp.delegate = self;”当启动cPopoverTapped IBAction时。现在运行良好，再次感谢。 – 2011-03-08 16:57:30

从弹出窗口类调用委托方法

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