Implement singleTap and doubleTap in Objective-C - ios

I add singTap and doubleTap to a view like the code below:
-(void)awakeFromNib{
[self setUserInteractionEnabled:YES];
//
UITapGestureRecognizer *doubleTapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleTapGesture:)];
doubleTapGesture.numberOfTapsRequired = 2;
[self addGestureRecognizer:doubleTapGesture];
UITapGestureRecognizer *singleTapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTapGesture:)];
singleTapGesture.numberOfTapsRequired = 1;
[self addGestureRecognizer:singleTapGesture];
}
-(void)handleSingleTapGesture:(UITapGestureRecognizer *)singleTapGesture{
[[self delegate] singleTapOnView];
}
-(void)handleDoubleTapGesture:(UITapGestureRecognizer *)doubleTapGesture{
[[self delegate] doubleTapOnView];
}
When doubleTap the singleTap also fire. How to disable singleTap when doubleTap? Thanks!

Tell the single-tap recognizer that it requires the double-tap recognizer to fail before it triggers:
[singleTapGesture requireGestureRecognizerToFail:doubleTapGesture];
(This is actually the canonical example in the UIGestureRecognizer docs for this method.)

Related

Adding both short long gestures in same view with proper differentiation

I am working on app in which I want both short long gesture in same view, I added but issue is I'm facing is that short gesture end always call, Need your help how to do that in right way. Below is my code.
UILongPressGestureRecognizer *longGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longGestureOnFormFields:)];
longGesture.minimumPressDuration = 1.0f;
[longGesture setDelegate:self];
[self addGestureRecognizer:longGesture];
UILongPressGestureRecognizer *shortGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(shortGesture:)];
shortGesture.minimumPressDuration = 0.1f;
[shortGesture setDelegate:self];
[self addGestureRecognizer:shortGesture];
- (void)longGestureOnFormFields:(UIGestureRecognizer*) recogniser
{
if (recogniser.state == UIGestureRecognizerStateEnded ) {
}
- (void)shortGesture:(UIGestureRecognizer*) recogniser
{
if (recogniser.state == UIGestureRecognizerStateEnded ) {
}
You can manage that by using one UITapGestureRecognizer like,
self.view.userInteractionEnabled = YES;
UILongPressGestureRecognizer *longGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longGestureOnFormFields:)];
longGesture.minimumPressDuration = 1.0f;
[longGesture setDelegate:self];
[self.view addGestureRecognizer:longGesture];
UITapGestureRecognizer *recog = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(testm)];
[self.view addGestureRecognizer:recog];
and your methods smething like,
-(void)testm{
NSLog(#"tap");
}
-(void)longGestureOnFormFields : (UILongPressGestureRecognizer*)sender{
if (sender.state == UIGestureRecognizerStateEnded ) {
NSLog(#"long press gesture");
}
}
I have added gesture recognizer in viewDidload i.e in viewcontroller so i have add it to self.view if you have subclass UIVIew and adding this to that view then add it on self like [self addgesture...] as shown in question!

Tao gesture method not triggered

i am trying to add gesture programmatically but messagesBucketTap method not print log
//
control=[self.storyboard instantiateViewControllerWithIdentifier:#"ControlScene"];
control.view.frame = CGRectMake(0, 0,control.view.frame.size.width,60);
[self.view addSubview:control.view];
//
UITapGestureRecognizer *messagesTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(messagesBucketTap:)];
[messagesTap setDelegate:self];
[messagesTap setNumberOfTapsRequired:1];
[messagesTap setNumberOfTouchesRequired:2];
[control.view addGestureRecognizer:messagesTap];
- (void)messagesBucketTap:(UITapGestureRecognizer *)gestureRecognizer{
NSLog(#"ramy'");}

UISwipeGestureRecognizer blocked by UITapGestureRecognizer

I have a view which needs to handle pan, tap, and swipe gestures. I have pan and tap working, but when I add swipe, it doesn't work. Curiously, it seems that tap somehow blocks the swipes because if I remove the tap, then swipe works fine. Here's how I create my gesture recognizers.
- (void) initGestureHandlers
{
UISwipeGestureRecognizer *swipeLeftGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeLeftGesture:)];
swipeLeftGesture.numberOfTouchesRequired = 1;
swipeLeftGesture.direction = UISwipeGestureRecognizerDirectionLeft;
[self addGestureRecognizer:swipeLeftGesture];
UISwipeGestureRecognizer *swipeRightGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeRightGesture:)];
swipeRightGesture.numberOfTouchesRequired = 1;
swipeRightGesture.direction = UISwipeGestureRecognizerDirectionRight;
[self addGestureRecognizer:swipeRightGesture];
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTapGesture:)];
[tapGesture setNumberOfTapsRequired:1];
[self addGestureRecognizer:tapGesture];
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handlePanGesture:)];
[self addGestureRecognizer:panGesture];
}
A lot of blog suggest using requireGestureRecognizerToFail to handle the case where tap fires before the double tap fires, so I tried that, but it also didn't work.
[tapGesture requireGestureRecognizerToFail:swipeLeftGesture];
[tapGesture requireGestureRecognizerToFail:swipeRightGesture];
How can I get tap and swipe in the same view?
comment or remove the lines
//[tapGesture requireGestureRecognizerToFail:swipeLeftGesture];
//[tapGesture requireGestureRecognizerToFail:swipeRightGesture];
Also set the all the guesture objects delegate to self. like this
- (void) initGestureHandlers
{
UISwipeGestureRecognizer *swipeLeftGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeLeftGesture:)];
swipeLeftGesture.numberOfTouchesRequired = 1;
swipeLeftGesture.direction = UISwipeGestureRecognizerDirectionLeft;
swipeLeftGesture.delegate = self;
[self addGestureRecognizer:swipeLeftGesture];
UISwipeGestureRecognizer *swipeRightGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeRightGesture:)];
swipeRightGesture.numberOfTouchesRequired = 1;
swipeRightGesture = self;
swipeRightGesture.direction = UISwipeGestureRecognizerDirectionRight;
[self addGestureRecognizer:swipeRightGesture];
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTapGesture:)];
[tapGesture setNumberOfTapsRequired:1];
[self addGestureRecognizer:tapGesture];
tapGesture.delegate = self;
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handlePanGesture:)];
[self addGestureRecognizer:panGesture];
panGesture.delegate = self;
}
Implement the delegate method like this
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
put this one and try it,
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer;
{
return YES;
}

UITapGestureRecognizer - single tap and double tap

I am trying to add 2 UITapGestureRecognizers to a view, one for single tap and one for double tap events. The single tap recognizer is working as expected (on its own). But I don't seem to be able to get the double tap recognizer working.
Have tried to experiment with properties like : cancelsTouchesInView, delaysTouchesBegan and delaysTouchesEnded but still doesn't work.
When I double tap, the single tap recognizer would always be activated and the double tap event would also be sent to the super view. But the custom double tap recognizer does not seem to be notified at all.
Documentations seem to suggest that the 3 properties mentioned above could be used for the purpose. But I am just not sure what values should be set and on which recognizer(s) (single, double or both). Hope somebody familiar with this could help.
The following is the latest updated code block.
// ****** gesture recognizers ******
- (void)addSingleAndDoubleTapGestureRecognizersToView:(UIView *)view
{
// single tap
UITapGestureRecognizer *singleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget: tableViewController action: #selector(handleSingleTapOnView:)];
[singleTapRecognizer setNumberOfTouchesRequired:1];
[view addGestureRecognizer: singleTapRecognizer];
// double tap
UITapGestureRecognizer *doubleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget: tableViewController action: #selector (handleDoubleTapOnView:)];
[doubleTapRecognizer setNumberOfTouchesRequired:2];
[singleTapRecognizer requireGestureRecognizerToFail: doubleTapRecognizer];
[view addGestureRecognizer: doubleTapRecognizer];
}
- (void)handleSingleTapOnView:(id)sender
{
}
- (void)handleDoubleTapOnView:(id)sender
{
}
UITapGestureRecognizer *singleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(doSingleTap)] autorelease];
singleTap.numberOfTapsRequired = 1;
[self.view addGestureRecognizer:singleTap];
UITapGestureRecognizer *doubleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(doDoubleTap)] autorelease];
doubleTap.numberOfTapsRequired = 2;
[self.view addGestureRecognizer:doubleTap];
[singleTap requireGestureRecognizerToFail:doubleTap];
Note: If you are using numberOfTouchesRequired it has to be .numberOfTouchesRequired = 1;
For Swift
let singleTapGesture = UITapGestureRecognizer(target: self, action: #selector(didPressPartButton))
singleTapGesture.numberOfTapsRequired = 1
view.addGestureRecognizer(singleTapGesture)
let doubleTapGesture = UITapGestureRecognizer(target: self, action: #selector(didDoubleTap))
doubleTapGesture.numberOfTapsRequired = 2
view.addGestureRecognizer(doubleTapGesture)
singleTapGesture.require(toFail: doubleTapGesture)
Swift 3 solution:
let singleTap = UITapGestureRecognizer(target: self, action:#selector(self.singleTapAction(_:)))
singleTap.numberOfTapsRequired = 1
view.addGestureRecognizer(singleTap)
let doubleTap = UITapGestureRecognizer(target: self, action:#selector(self.doubleTapAction(_:)))
doubleTap.numberOfTapsRequired = 2
view.addGestureRecognizer(doubleTap)
singleTap.require(toFail: doubleTap)
In the code line singleTap.require(toFail: doubleTap) we are forcing the single tap to wait and ensure that the tap event is not a double tap.
You need to use the requireGestureRecognizerToFail: method. Something like this:
[singleTapRecognizer requireGestureRecognizerToFail:doubleTapRecognizer];
//----firstly you have to alloc the double and single tap gesture-------//
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];
//-----------------------number of tap----------------//
[doubleTap setNumberOfTapsRequired : 2];
[singleTap setNumberOfTapsRequired : 1];
//------- add double tap and single tap gesture on the view or button--------//
[self.view addGestureRecognizer : doubleTap];
[self.view addGestureRecognizer : singleTap];
Not sure if that's exactly what are you looking for, but I did single/double taps without gesture recognizers. I'm using it in a UITableView, so I used that code in the didSelectRowAtIndexPath method
tapCount++;
switch (tapCount)
{
case 1: //single tap
[self performSelector:#selector(singleTap:) withObject: indexPath afterDelay: 0.2];
break;
case 2: //double tap
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:#selector(singleTap:) object:indexPath];
[self performSelector:#selector(doubleTap:) withObject: indexPath];
break;
default:
break;
}
if (tapCount>2) tapCount=0;
Methods singleTap and doubleTap are just void with NSIndexPath as a parameter:
- (void)singleTap:(NSIndexPath *)indexPath {
//do your stuff for a single tap
}
- (void)doubleTap:(NSIndexPath *)indexPath {
//do your stuff for a double tap
}
Hope it helps
Solution for Swift 2:
let singleTapGesture = UITapGestureRecognizer(target: self, action: #selector(handleSingleTap))
singleTapGesture.numberOfTapsRequired = 1 // Optional for single tap
view.addGestureRecognizer(singleTapGesture)
let doubleTapGesture = UITapGestureRecognizer(target: self, action: #selector(handleDoubleTap))
doubleTapGesture.numberOfTapsRequired = 2
view.addGestureRecognizer(doubleTapGesture)
singleTapGesture.requireGestureRecognizerToFail(doubleTapGesture)
I implemented UIGestureRecognizerDelegate methods to detect both singleTap and doubleTap.
Just do this .
UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(handleDoubleTapGesture:)];
[doubleTap setDelegate:self];
doubleTap.numberOfTapsRequired = 2;
[self.headerView addGestureRecognizer:doubleTap];
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(handleSingleTapGesture:)];
singleTap.numberOfTapsRequired = 1;
[singleTap setDelegate:self];
[doubleTap setDelaysTouchesBegan:YES];
[singleTap setDelaysTouchesBegan:YES];
[singleTap requireGestureRecognizerToFail:doubleTap];
[self.headerView addGestureRecognizer:singleTap];
Then implement these delegate methods.
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch{
return YES;
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
return YES;
}
Some view have there own double tap recognizers built in (MKMapView being an example). To get around this you will need to implement UIGestureRecognizerDelegate method shouldRecognizeSimultaneouslyWithGestureRecognizer and return YES:
First implement your double and single recognizers:
// setup gesture recognizers
UITapGestureRecognizer* singleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(mapViewTapped:)];
singleTapRecognizer.delegate = self;
singleTapRecognizer.numberOfTapsRequired = 1;
UITapGestureRecognizer* doubleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(mapViewDoubleTapped:)];
doubleTapRecognizer.delegate = self; // this allows
doubleTapRecognizer.numberOfTapsRequired = 2;
[singleTapRecognizer requireGestureRecognizerToFail:doubleTapRecognizer];
And then implement:
#pragma mark UIGestureRecognizerDelegate
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer
*)otherGestureRecognizer { return YES; }
In reference to #stanley's comment -
Don't try and use tap gestures to row selections to work in UITableView as it already has full tap handling....
But you must set 'Cancels Touches in View' to 'NO' on your single tap gesture recognizers or it will never get the tap events.

Problem with UITapGestureRecognizer for double tap

I've two UITapGestureRecognizer: singleTap and doubleTap initialized with two different actions.
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleTap:)];
[singleTap requireGestureRecognizerToFail:doubleTap];
[doubleTap setNumberOfTapsRequired:2];
[imageView addGestureRecognizer:doubleTap];
[imageView addGestureRecognizer:singleTap];
When I run my app in simulator the single tap responds correctly but not the double tap ! When I double clicks nothings happens, I suppose iOS dose recognize the double tap because the action of single tap doesn't being called (due to [singleTap requireGestureRecognizerToFail:doubleTap];), but I can't understand why doesn't it do the action handleDoubleTap.
I think the problem is that UIImageView and UILabel both override the default value of YES for the userInteractionEnabled property, and sets it to NO.
Add imageView.userInteractionEnabled = YES; and try again.
The following code works for me:
- (void)handleTap:(UIGestureRecognizer*)gr {
NSLog(#"----------------- tap ----------------");
}
- (void)handleDoubleTap:(UIGestureRecognizer*)gr {
NSLog(#"================= double tap ============");
}
- (XXXView*)createXXXView {
XXXView *view = [[[XXXView alloc] init] autorelease];
view.xxx=...;//irrelevant
UITapGestureRecognizer *dtr = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleTap:)];
dtr.numberOfTapsRequired = 2;
UIGestureRecognizer *tr = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
[tr requireGestureRecognizerToFail:dtr];
[view addGestureRecognizer:tr];
[view addGestureRecognizer:dtr];
return view;
}

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