Question

I am working on a splitView application for my iPad. I have implemented a UIButton called as Upload. On clicking on it, a UITableView appears inside a UIPoverController. On clicking on any of the contents, I want to display some respective site in my UIwebView in UIDetailView. For this I have implemented a delegate method protocol. I have used the following lines of code in UploadTableViewController.h file::

@protocol UploadTableViewDelegate <NSObject>
@required
- (void)selected:(NSString *)his;
@end


 @interface UploadSpaceTableViewController : UITableViewController{
id<UploadSpaceTableViewDelegate> delegate;
}

@property (retain) id delegate;
@end

In the corresponding .m file I have used the following lines of code ::

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{

if (delegate != nil) {
    NSString *hisSelected = [keys objectAtIndex:indexPath.row];
    NSLog(@"%@ lolwa", hisSelected);
    [delegate selected:hisSelected];
}

}

in the .m file of class where I have implemented the function Selected, the code is ::

- (void)selected:(NSString *)Key {    
  NSLog(@"hello");    
  [self.UploadSpaceTableViewPopover dismissPopoverAnimated:YES];
}


-(IBAction)uploadpressed:(id)sender{  
Upload.delegate = self;
self.Upload = [[UploadSpaceTableViewController alloc] 
                         initWithStyle:UITableViewStylePlain];
self.UploadTableViewPopover = [[UIPopoverController alloc] 
                                initWithContentViewController:UploadSpace];               

[self.UploadTableViewPopover presentPopoverFromBarButtonItem:sender 
                                permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
 }

However, I am unable to get hello (written in the function Selected) NSLogged in gdb. This is the first time that I am using this delegate method protocol. I am unable to sort this out. Can someone help me out ? Thanks and regards.

Answer 1

Delegation works like this

• declare a protocol – you have done this
• declare a delegate property – you have done this

• In the class which you want to be the delegate say it conforms to the protocoll

  @interface MyClass : MySuperClass <UploadTableViewDelegate>

• set the delegate property so the delegate class can get the delegate messages

  uploadSpaceTVC.delegate = self;

• call the delegate methods in your non delegate class (UploadSpaceTableViewController)

  [self.delegate selected:@"test"];