使用自定义表格视图单元格中的按钮

Question

I have a facebook like button in a custom tableview cell. In the class of my tableview I have the following function.

- (IBAction)sendLike:(id)sender
          WithString: (NSString *)shareString
              andUrl:(NSURL *)shareUrl{

          //Do all kinds of things


        [fbController setInitialText:shareString];
        [fbController addURL:shareUrl];
        [fbController setCompletionHandler:completionHandler];
        [self presentViewController:fbController animated:YES completion:nil];
    }
}

In my cellForRowAtIndexpath I am trying to call this method in the following way.

 NSString *shareString = video.name;
        NSURL *shareUrl = [NSURL URLWithString:video.url];
        [cell.facebook addTarget:self action:@selector(sendLike: WithString:shareString andUrl:shareUrl)
                 forControlEvents:UIControlEventTouchUpInside];

But it is complaining that I should put ':' in my @selector. Can anybody help ?

Thanks in advance.

Answer 1

You can try like this

cell.facebook.tag = indexPath.row.
    [cell.facebook addTarget:self action:@selector(sendLike:)
                     forControlEvents:UIControlEventTouchUpInside];

in sendLike event

- (IBAction)sendLike:(id)sender
  {


        //if you want to fetch data from any list then try
        //UIButton *selectedButton = (UIButton*)sender;
        //data = [dataList objectAtIndex:selectedButton.tag];
        NSString *shareString = video.name;
        NSURL *shareUrl = [NSURL URLWithString:video.url];

        [fbController setInitialText:shareString];
        [fbController addURL:shareUrl];
        [fbController setCompletionHandler:completionHandler];
        [self presentViewController:fbController animated:YES completion:nil];
    }

Answer 2

As its in the apple documentation, the only available specifications for an @selector in an action are the following methods:

- (void)action;

- (void)action:(id)sender;

- (void)action:(id)sender forEvent:(UIEvent *)event;

As you can see, your selector doesn't match this, because you have multiple arguments, but only the sender id is allowed.

As a solution, you can probably set a tag for your button and then handle it in your selector.

Answer 3

In your cellForRow : //wiring a custom string to a button

objc_setAssociatedObject(yourButton, "theKey", strText, OBJC_ASSOCIATION_RETAIN_NONATOMIC);

In your button handler:

NSString *str = objc_getAssociatedObject(sender, "theKey");

ps don't forget to import runtime library: #import <objc/runtime.h>

Answer 4

I think you invoked the selector in wrong way. You actually should write,

[cell.facebook addTarget:self action:@selector(sendLike: WithString: andUrl:)  
                                     forControlEvents:UIControlEventTouchUpInside];  

But this doesn't pass arguments for you. If you want to pass arguments, you should call performSelector like

[self performSelector:@selector(sendLike: WithString: andUrl:) 
                                withObject: cell.facebook
                                withObject: shareString
                                withObject: shareUrl]; 

Hope it will help solving your problem.

Answer 5

Your problem is that the number and kind of arguments are incorrect in your selector. You can only use targets with the following scheme:

 - (void)action;
 - (void)action:(id)sender;
 - (void)action:(id)sender forEvent:(UIEvent *)event;

You will have to include your information in the sender (the UITableViewCell class instance) object. You can do that as described in the other answer by Stas, but I would recommend you to create a custom table view cell subclass which adds a property for shareString and shareURL . This approach will require more code, but make it much easier to read, maintain and prevents this ugly Obj-C and C mix up.