UILongPressGestureRecognizer *longPressOnUndoGesture = [[UILongPressGestureRecognizer alloc]
initWithTarget:self
action:#selector(handleLongPressOnUndoGesture:)];
[longPressOnUndoGesture setMinimumPressDuration:2.0];
[longPressOnUndoGesture release];
i have the above code to deasctivate the autoscroll timer in my applicationthis is the function for this.
-(void) handleLongPressOnUndoGesture:(UILongPressGestureRecognizer*)recognizer {
[autoscrollTimer invalidate];
}
but when i taptohold for 2 seconds it wont stop the timer.is there any error in my code for gesture.
Thanks in advance.
You're not using the gesture recognizer, as you release it immediately as you created it. You have to attach it to a view like this:
UILongPressGestureRecognizer *longPressOnUndoGesture = [[UILongPressGestureRecognizer alloc]
initWithTarget:self
action:#selector(handleLongPressOnUndoGesture:)];
[longPressOnUndoGesture setMinimumPressDuration:2.0];
// TRICK HERE
[self.view addGestureRecognizer:longPressUndoGesture];
[longPressOnUndoGesture release];
It seems to me that you are not adding the gesture recognizer to the view it should work upon:
[self.view addGestureRecognizer: longPressOnUndoGesture];
(if self is your controller).
Related
Can i show a Tool tip like this:
Also, I want to show this tool tip when that area is pressed and HOLD. Is there a handler for this gesture?
You can do that in didSelectRowAtIndex method of TableViewController delegate method.
Look here. It is best implementation to have Popover controllers in iPhone. Download run and integrate into your code and change according to your requirement.
In addition to what #jennis said, there is indeed a way to capture long hold gestures you could use UILongPressGestureRecognizer
like this
UILongPressGestureRecognizer *gesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longHold)];
[cell addGestureRecognizer:gesture];
and longHold method
- (void) longHold
{
//Cell has recieved gesture
}
It works, I agree with Omar Abdelhafith
-(void)viewWillAppear:(BOOL)animated
{ //gesture declared in .h file
gesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longHold)];
[your view addGestureRecognizer:gesture];
}
-(void)longHlod
{
//do whatever you want
}
I'm using UILongPressGestureRecognizer class to handle if one item is being selected.
The logic is as follows: User press during 1 second an item (UIView subclass). Once the gesture is detected, the item is highlighted and moveable.
The user must move this item across the screen without stop touching it.
The problem I'm facing is the gesture recognized shadows touchesBegan/Move/Ended necessary for the item class to arrange the movement.
I tried to remove the gesture recognized once is detected and the item selected. But still sending messages to the handle of gesture instead of call touches methods.
Anyone knows any way to stop "listening" the gesture recognizer without leave the finger of the screen?
Thanks.
Here the code:
-(void)addGestures
{
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc]
initWithTarget:self
action:#selector(handleLongPress:)];
longPress.minimumPressDuration = iItemLongPressTime;
[self addGestureRecognizer:longPress];
[longPress release];
}
- (void)handleLongPress:(UILongPressGestureRecognizer*)sender {
if (sender.state == UIGestureRecognizerStateEnded) {
NSLog(#"Long press Ended");
}
else {
if (self.isSelected) return;
if ([delegate respondsToSelector:#selector(singleTouch:)])
[delegate singleTouch:self];
[self removeGestureRecognizer:[self.gestureRecognizers objectAtIndex:0]];
NSLog(#"Long press detected.");
}
}
As you can see in the else branch the delegate calls enables all procedures to mark this item as selected, and just after remove the recognizers.
What I'm missing?
--EDIT--
Done! This works:
#pragma mark Gesture Functions
-(void)addGestures
{
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc]
initWithTarget:self
action:#selector(handleLongPress:)];
longPress.minimumPressDuration = iItemLongPressTime;
[self addGestureRecognizer:longPress];
[longPress release];
}
- (void)handleLongPress:(UILongPressGestureRecognizer*)sender {
if (sender.state == UIGestureRecognizerStateEnded) {
NSLog(#"Long press Ended");
}
else {
NSLog(#"Long press detected.");
if (self.isSelected) return;
if ([delegate respondsToSelector:#selector(singleTouch:)])
[delegate singleTouch:self];
[sender removeTarget:self action:#selector(handleLongPress:)];
sender.enabled = NO;
[self removeGestureRecognizer:sender];
}
}
Regards!
Does the custom UIView class have its own touch handling code? If not, a simple solution is to set the allowableMovement property of the UILongPressGestureRecognizer to CGFLOAT_MAX, or some big number, and use the gesture update callbacks to drag your custom view around. You can get the displacement using the - (CGPoint)locationInView:(UIView *)view method on the superview, and compare its position to when the recognizer began.
There are two solutions in my mind.
For animating uiview, please wrote a new class which is inherited from the UIView class and implement the touch delegates instead of writing the Gustures to handle animation(if the touch delegates are not triggering in the current class).
2.I have successfully removed the UILongPressGestureRecognizer after triggered it once.
Please refer the below code .ask me if you have any queries
Steps I have Done
I have added a UIView as "myView" to my main-view when main-view loads.
I have given the Tag to the myView (you can give 1,2,3…etc) to differentiate the tapped view from the main-view subviews.
Assigned the UILongPressGestureRecognizer gesture to myView and assigned target as "moveMe" method.
When user Pressed the myView long, the "moveMe" method will trigger.
Then I iterated the mainView Subviews with the condition Tag == 1
I have removed the UILongPressGestureRecognizer from the subview.As we can know that Tagged 1 main-view subView is myView.
So the NSLog(#"gesture removed"); and NSLog(#"moveMe"); will log in console only at one time.
The NSLog(#"touchesBegan"); will trigger first instead of triggering the "moveMe" method.
Then NSLog(#"touchesBegan"); will trigger always after removed the gesture . "moveMe" method will not trigger ever.
Code
- (void)viewDidLoad {
//Adding to UIView to main view when application is loading.
UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(20, 20, 80, 80)];
myView.backgroundColor = [UIColor viewFlipsideBackgroundColor];
myView.tag = 1; //adding a tag to identify it.
//Adding Long Press Gesture to the UIView.
UILongPressGestureRecognizer *myGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(moveMe:)];
[myView addGestureRecognizer:myGesture];
[myGesture release];
myGesture = nil;
[self.view addSubview:myView];
[myView release];
myView = nil;
[super viewDidLoad];
}
//Method to trigger when user pressed long on the added UIView.
-(void)moveMe:(id)sender
{
for (UIView *subViews in [self.view subviews])
{
if (subViews.tag == 1) {
[subViews removeGestureRecognizer:sender];
NSLog(#"gesture removed");
}
}
NSLog(#"moveMe");
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"touchesBegan");
}
or please refer Disable gesture recognizer iOS
I'm using the code below to integrate right/left swipe events to a UIImageView object (called photo_view) but it did not work after tests in iphone simulator and device. The methods handleLeftSwipe and handleRightSwipe below are not even called as logging didn't print anything in the debugger logs as it should. Here is the code:
- (void)viewDidLoad
{
[super viewDidLoad];
UISwipeGestureRecognizer *leftSwipeRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleLeftSwipe:)];
leftSwipeRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
leftSwipeRecognizer.numberOfTouchesRequired = 1;
[photo_view addGestureRecognizer:leftSwipeRecognizer];
leftSwipeRecognizer.delegate = self;
[leftSwipeRecognizer release];
UISwipeGestureRecognizer *rightSwipeRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleRightSwipe:)];
rightSwipeRecognizer.direction = UISwipeGestureRecognizerDirectionRight;
rightSwipeRecognizer.numberOfTouchesRequired = 1;
[photo_view addGestureRecognizer:rightSwipeRecognizer];
rightSwipeRecognizer.delegate = self;
[rightSwipeRecognizer release];
}
- (void)handleLeftSwipe:(UISwipeGestureRecognizer *)recognizer
{
NSLog(#"handleLeftSwipe called");
}
- (void)handleRightSwipe:(UISwipeGestureRecognizer *)recognizer
{
NSLog(#"handleRightSwipe called");
}
Any idea what the reason ?
Thx in advance for helping,
Stephane
UIImageView instances defaults userInteractionEnabled to NO. Try setting it to YES.
Make Sure you're also including the <UIGestureRecognizerDelegate> in your .h file.
I've got splite-view application and of course there is a popover controller in the vertical DetailView, how can I hide with double-tap? thanks
You have to add a doubleTap gesture recognizer and call dismissPopoverAnimated:
First declare a gesture recognizer and configure it to your view:
UITapGestureRecognizer * doubleTapGesture = [[UIGestureRecognizer alloc] initWithTarget:self action:#selector(doubleTapCallback:)];
doubleTapGesture.numberOfTapsRequired = 2;
[yourView addGestureRecognizer:doubleTapGesture];
[doubleTapGesture release];
Then implement the callback:
- (IBAction) doubleTapCallback: (UITapGestureRecognizer *) sender
{
[yourPopOverController dismissPopoverAnimated:YES]
}
I have a UITextField that is the subview of UIScrollView
I have there exist a single tap gesture (or perhaps the older touch) as part of UITextField that makes it the first responder. I wanted to add a double tap Gesture to the UITextField. In order to make the two Gesture's mutually exclusive I needed to overload (though this is not quite the right word because I'm not using the same name) the single tap Gesture. When I do it works fine so long as the function that it calls doesn't make the UITextField the first responder. If it does make the textfield the first responder it fails the second time it's called.... wtf. So stack, a little help would go a long way.
this is where I add the gesture
UITapGestureRecognizer * singleTextTap = [[UITapGestureRecognizer alloc]
initWithTarget:self action:#selector(handleSingleTextTap:)];
singleTextTap.numberOfTapsRequired = 1;
[aTextField addGestureRecognizer:singleTextTap];
and this is where it is called
//single tap text
- (void) handleSingleTextTap:(UITapGestureRecognizer *)gestureRecognizer{
NSLog(#"handling single tap");
NSLog(#"textField gestures %#",
[gestureRecognizer.view.gestureRecognizers descriptionWithLocale:nil]);
[(UITextField *)gestureRecognizer.view becomeFirstResponder];
}
you may notice the NSLog that out puts the gestuers registered to the textField this was to check the state of my singleTextTap gesture. which is 'ended' the first time and all next times this code is never reached
The behaviour you're seeing is due to each time you send a becomeFirstResponder message to a UITextField it sets it's own gesture recognizers up. If you do a log on [textField gestureRecognizers] you'll see it sets up a lot of them. These are to deal with text editing functions such as long press for cursor movement and such. By way of adding these it cancels the ones you have setup. Easiest way to deal with this is something like this.
- (void) singleTap:(UITapGestureRecognizer*)singleTap {
if (![self.textField isFirstResponder]) {
[self.textField becomeFirstResponder];
self.label.text = #"Single Tap -> Make First Responder";
[self.label setNeedsDisplay];
}
}
- (void) doubleTap:(UITapGestureRecognizer*)doubleTap {
if (![self.textField isFirstResponder]) {
[self.textField becomeFirstResponder];
self.label.text = #"Double Tap -> Make First Responder";
[self.label setNeedsDisplay];
}
}
- (void) setupTextGestureRecognizers {
for (UIGestureRecognizer *rec in self.textField.gestureRecognizers) {
[self.textField removeGestureRecognizer:rec];
}
UITapGestureRecognizer *singleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTap:)] autorelease];
UITapGestureRecognizer *doubleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(doubleTap:)] autorelease];
[singleTap setNumberOfTapsRequired:1];
[doubleTap setNumberOfTapsRequired:2];
[singleTap setCancelsTouchesInView:YES];
[doubleTap setCancelsTouchesInView:YES];
[singleTap requireGestureRecognizerToFail:doubleTap];
[self.textField addGestureRecognizer:singleTap];
[self.textField addGestureRecognizer:doubleTap];
}
- (void)viewDidLoad {
[super viewDidLoad];
[self setupTextGestureRecognizers];
self.textField.delegate = self;
}
- (BOOL) textFieldShouldReturn:(UITextField *)tf {
[tf resignFirstResponder];
if (tf == self.textField) {
[self setupTextGestureRecognizers];
}
return YES;
}
Here is an example project demonstrating this code in use.
What you're doing seems really strange, but whatever. I'll assume you know what you're doing.
You might try the following:
UITapGestureRecognizer *doubleTap = ...;
UITapGestureRecognizer *singleTap = ...;
[singleTap requireGestureRecognizerToFail:doubleTap];
This means that the single tap recognizer will only fire if the double tap one doesn't fire, effectively making them mutually exclusive.