can a titleView be made to accept tap gestures? - ios

Question

In a custom class MMTimerButton, I set up the button to respond to a single and a double tap
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
[self setBackgroundColor: [UIColor clearColor]];
UITapGestureRecognizer *singleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
singleTapRecognizer.numberOfTapsRequired=1;
singleTapRecognizer.delaysTouchesEnded=YES;
UITapGestureRecognizer *doubleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleTap:)];
doubleTapRecognizer.numberOfTapsRequired=2;
[singleTapRecognizer requireGestureRecognizerToFail: doubleTapRecognizer];
[self addGestureRecognizer:singleTapRecognizer];
[self addGestureRecognizer:doubleTapRecognizer];
}
return self;
}
I implement the two methods like this in the same file
-(void)handleTap:(UITapGestureRecognizer *)sender{
NSLog(#"single tap");
}
-(void)handleDoubleTap:(UITapGestureRecognizer *)sender{
NSLog(#"double tap");
}
In the header, I declare two methods
#import <UIKit/UIKit.h>
#interface MMTimerButton : UIButton
-(void)handleTap:(UITapGestureRecognizer *)sender;
-(void)handleDoubleTap:(UITapGestureRecognizer *)sender;
In the storyboard, I added a button to the interface and set its custom class to be MMTimerButton.
Nothing's happening when I click the button (in the simulator). One click, two click, both nothing.
I also tried doing it without a button, just adding gesture recognizers to the titleView. Nothing happens when I click on the title in the simulator
UITapGestureRecognizer* doubleTap = [[UITapGestureRecognizer alloc] initWithTarget : self action : #selector (handleDoubleTap:)];
UITapGestureRecognizer* singleTap = [[UITapGestureRecognizer alloc] initWithTarget : self action : #selector (handleSingleTap:)];
[singleTap requireGestureRecognizerToFail : doubleTap];
[doubleTap setDelaysTouchesBegan : YES];
[singleTap setDelaysTouchesBegan : YES];
[doubleTap setNumberOfTapsRequired : 2];
[singleTap setNumberOfTapsRequired : 1];
self.navigationItem.title =#"title";
[self.navigationItem.titleView addGestureRecognizer:doubleTap];
[self.navigationItem.titleView addGestureRecognizer:singleTap];
However, when I add this code to header view, it works fine (in the simulator)
-(UIView*)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
UILabel *headerLabel = [[UILabel alloc]init];
headerLabel.tag = section;
headerLabel.userInteractionEnabled = YES;
headerLabel.backgroundColor = [UIColor clearColor];
headerLabel.text = [NSString stringWithFormat:#"0:00",section];
headerLabel.textAlignment = UITextAlignmentCenter;
headerLabel.frame=CGRectMake(10,-5,tableView.frame.size.width,41);
UITapGestureRecognizer* doubleTap = [[UITapGestureRecognizer alloc] initWithTarget : self action : #selector (handleDoubleTap:)];
UITapGestureRecognizer* singleTap = [[UITapGestureRecognizer alloc] initWithTarget : self action : #selector (handleSingleTap:)];
[singleTap requireGestureRecognizerToFail : doubleTap];
[doubleTap setDelaysTouchesBegan : YES];
[singleTap setDelaysTouchesBegan : YES];
[doubleTap setNumberOfTapsRequired : 2];
[singleTap setNumberOfTapsRequired : 1];
self.navigationItem.title =#"title";
[headerLabel addGestureRecognizer:doubleTap];
[headerLabel addGestureRecognizer:singleTap];
return headerLabel;
//return nil;
}

Answer 1

You are showing a lot of troubled code here, so it's hard to know where to start.
In the case of your initWithFrame:, the problem is that this method is never called for a button. Moreover, you've got a conflict because the button already contains the ability to respond to a tap, internally (it's a button!).
In the second set of code, you never set the titleView to a view, so it is nil, and your code does nothing. Also, you can't set both the title and the titleView (you are setting the title).
The answer to your title question is, of course a titleView can respond to a tap. Lots of apps do this (including mine).
Also, you do not need your requireGestureRecognizerToFail - a single tap gesture recognizer and a double tap gesture recognizer already know how to mediate between themselves.
So basically my advice would be: stop over-complicating everything. Don't make big assumptions and dive in. Start with stuff that you know works and take little steps. Test everything with logging / breakpoints as you go, to see that what's happening is what you imagine.