Objective-c : action:#selector(xxxxxx) not called - objective-c

Question

I'm currently trying to add a button to my app. If the user push on it, it should display an alert.
I want to add the button to a section header of a tableview. Here is my code in tableView:viewForHeaderInSection:
UIImageView *headerView = [[[UIImageView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 20)] autorelease];
...
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setFrame:CGRectMake(180, 4, 15, 15)];
UIImage *img=[UIImage imageNamed:#"myimg"];
[button setImage:img forState:UIControlStateNormal];
[button addTarget:self action:#selector(showMyAlert) forControlEvents:UIControlEventTouchUpInside];
[headerView addSubview:button];
return headerView;
And in the same class, I have the method :
-(void)showMyAlert{
NSLog(#"HERE SHOW ALERT");
...
}
The button is correctly displayed but the showMyAlert method is never called when I push on it.
Does anyone have an idea of what is wrong with my code ?
Thanks if you could help me :)

Answer 1

Change your UIImageView as UIView and return it as the header view.
UIView *headerView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 20)] autorelease];

Answer 2

Make sure img is not nil. If that is nil, your button will have no image and you will see nothing.

Answer 3

Modified below lines of code, Try like this:-
[button addTarget:self action:#selector(showMyAlert:) forControlEvents:UIControlEventTouchUpInside];
-(IBAction)showMyAlert:(id)sender{
NSLog(#"HERE SHOW ALERT");
...
}

Answer 4

Try this, in viewDidLoad,
-(void)viewDidLoad
{
UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(XXX, YYY, XXX, YYY)];
UIImageView *imageView = [[[UIImageView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 20)] autorelease];
[headerView addSubview:imageView];
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setFrame:CGRectMake(180, 4, 15, 15)];
UIImage *img=[UIImage imageNamed:#"myimg"];
[button setImage:img forState:UIControlStateNormal];
[button addTarget:self action:#selector(showMyAlert) forControlEvents:UIControlEventTouchUpInside];
[headerView addSubview:button];
self.tableView.tableHeaderView = headerView;
}