i set a UITapGesture on my scrollView but because of that i can't use the button inside my scrollView... all it reads is the action of the gesture for the scrollView.
how am i gonna able to fix that?
i have this code:
UIGestureRecognizer *tapIt = [[ UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
imgTap = (UITapGestureRecognizer *)tapIt;
imgTap.numberOfTapsRequired = 1;
imgTap.numberOfTouchesRequired = 1;
[scrollView addGestureRecognizer:imgTap];
Try to prevent the touch from reaching the button in the gesture delegate:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch{
if ([touch.view isDescendantOfView:myButton]) {
return NO;
}
return YES;
}
I believe you can set cancelsTouchesInView property on your gesture to NO. Also there should be some method to ignore gestures in some parts of a view.
Related
I have a PageViewController which is initialized like this:
self.pageViewController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStyleScroll
navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options:nil];
On one of the pages, there's a UISlider.
My problem is that when I have transitionstyle set to UIPageViewControllerTransitionStyleScroll, it takes 150-200 ms before beginTrackingWithTouch is invoked on the slider.
This behavior is not seen when I use UIPageViewControllerTransitionStylePageCurl, where the UISlider is selected instantly.
This means that unless the user waits a bit before dragging the slider (a video progress), the page will turn instead, which is far from ideal.
The Page curl animation does not meet the demands of the app, so any explanation or workaround is appreciated.
Since with UIPageViewControllerTransitionStyleScroll gesture recognizers isn't available, you can use this:
for (UIView *view in pageViewController.view.subviews) {
if ([view isKindOfClass:[UIScrollView class]]) {
UIScrollView *scrollView = (UIScrollView *)view;
scrollView.delaysContentTouches = NO;
}
}
I solved this issue by add a pan gesture on UISlider and set:
self.sliderGesture.cancelsTouchesInView = NO; // make touch always triggered
and implement delegate method like:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return otherGestureRecognizer.view.superview == self.parentViewController.view;
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
// only receive touch in slider
CGPoint touchLocation = [touch locationInView:self.view];
return CGRectContainsPoint(self.slider.frame, touchLocation);
}
You can try to set the delegate of the page view controller gestures to the root view controller:
for (UIGestureRecognizer* gestureRecognizer in self.pageViewController.gestureRecognizers) {
gestureRecognizer.delegate = self;
}
And then prevent the touch of the gestures if it appears inside UISlider which is a subclass of UIControl:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
return ([touch.view isKindOfClass:[UIControl class]] == NO);
}
What helped me was to add pan-gesture-recognizer to UIView which holds UISlider, so in the end I have
UIPageViewController->UIScrollView->...->MyView->UISlider
The 'MyView' thing had pan gesture registered to it which did nothing, but served just to NOT propagate events to scroll view.
Is there a way to do this? Like tapping on any part of the screen dismisses the partial modal curl.
I thought about an invisible button, but that still doesn't cover the whole curl area.
Add gesture recognizers to your main view in viewDidLoad
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(getDismissed)];
UISwipeGestureRecognizer *swipeRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self
action:#selector(getDismissed)];
swipeRecognizer.direction = UISwipeGestureRecognizerDirectionDown;
tapRecognizer.numberOfTapsRequired = 1;
tapRecognizer.numberOfTouchesRequired = 1;
tapRecognizer.delegate = self;
[self.view addGestureRecognizer:tapRecognizer];
[self.view addGestureRecognizer:swipeRecognizer];
-(void)getDismissed
{
// call dismissViewControllerAnimated:completion: by the presenting view controller
// you can use delegation or direct call using presentingViewController property
}
Then exclude in view that you don't want to trigger the dismissal
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
// touching objects of type UIControl will not dismiss the view controller
return ![touch.view isKindOfClass:[UIControl class]];
}
I have a viewcontroller that via "[self.view addSubview: secondView.view]," adds a second view. The problem is that the second view is added outside half.
secondView = [[SecondView alloc] initWithFrame: CGRectMake (-160, 0, 320, 460)];
[self.view addSubview: secondView.view]; "
I have noticed, however, that the part before the 0 (-160) is not interagibile. Is this normal? is there a way to solve?
Thank you!
You can allow subviews to receive touches outside of the parent's bounds by overriding pointInside:withEvent: for the parent view.
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
BOOL pointInside = NO;
// step through our subviews' frames that exist out of our bounds
for (UIView *subview in self.subviews)
{
if(!CGRectContainsRect(self.bounds, subview.frame) && [subview pointInside:[self convertPoint:point toView:subview] withEvent:event])
{
pointInside = YES;
break;
}
}
// now check inside the bounds
if(!pointInside)
{
pointInside = [super pointInside:point withEvent:event];
}
return pointInside;
}
I fear that given the way the UIResponder chain works, what you want is not directly possible (the superview will only pass to its subviews the events that it recognizes as affecting itself).
On the other hand, if you really need to have this view outside of its parent's frame, you could associate a gesture recognizer (reference) to the subview. Indeed, gesture recognizers are handled outside the normal touch event dispatching and it should work.
Try this for a tap:
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
[secondView addGestureRecognizer:singleTap];
I'm trying to figure out how this is done the right way. I've tried to depict the situation:
I'm adding a UITableView as a subview of a UIView. The UIView responds to a tap- and pinchGestureRecognizer, but when doing so, the tableview stops reacting to those two gestures (it still reacts to swipes).
I've made it work with the following code, but it's obviously not a nice solution and I'm sure there is a better way. This is put in the UIView (the superview):
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
if([super hitTest:point withEvent:event] == self) {
for (id gesture in self.gestureRecognizers) {
[gesture setEnabled:YES];
}
return self;
}
for (id gesture in self.gestureRecognizers) {
[gesture setEnabled:NO];
}
return [self.subviews lastObject];
}
I had a very similar problem and found my solution in this SO question. In summary, set yourself as the delegate for your UIGestureRecognizer and then check the targeted view before allowing your recognizer to process the touch. The relevant delegate method is:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldReceiveTouch:(UITouch *)touch
The blocking of touch events to subviews is the default behaviour. You can change this behaviour:
UITapGestureRecognizer *r = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(agentPickerTapped:)];
r.cancelsTouchesInView = NO;
[agentPicker addGestureRecognizer:r];
I was displaying a dropdown subview that had its own tableview. As a result, the touch.view would sometimes return classes like UITableViewCell. I had to step through the superclass(es) to ensure it was the subclass I thought it was:
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
UIView *view = touch.view;
while (view.class != UIView.class) {
// Check if superclass is of type dropdown
if (view.class == dropDown.class) { // dropDown is an ivar; replace with your own
NSLog(#"Is of type dropdown; returning NO");
return NO;
} else {
view = view.superview;
}
}
return YES;
}
Building on #Pin Shih Wang answer. We ignore all taps other than those on the view containing the tap gesture recognizer. All taps are forwarded to the view hierarchy as normal as we've set tapGestureRecognizer.cancelsTouchesInView = false. Here is the code in Swift3/4:
func ensureBackgroundTapDismissesKeyboard() {
let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(handleTap))
tapGestureRecognizer.cancelsTouchesInView = false
self.view.addGestureRecognizer(tapGestureRecognizer)
}
#objc func handleTap(recognizer: UIGestureRecognizer) {
let location = recognizer.location(in: self.view)
let hitTestView = self.view.hitTest(location, with: UIEvent())
if hitTestView?.gestureRecognizers?.contains(recognizer) == .some(true) {
// I dismiss the keyboard on a tap on the scroll view
// REPLACE with own logic
self.view.endEditing(true)
}
}
One possibility is to subclass your gesture recognizer (if you haven't already) and override -touchesBegan:withEvent: such that it determines whether each touch began in an excluded subview and calls -ignoreTouch:forEvent: for that touch if it did.
Obviously, you'll also need to add a property to keep track of the excluded subview, or perhaps better, an array of excluded subviews.
It is possible to do without inherit any class.
you can check gestureRecognizers in gesture's callback selector
if view.gestureRecognizers not contains your gestureRecognizer,just ignore it
for example
- (void)viewDidLoad
{
UITapGestureRecognizer *singleTapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
singleTapGesture.numberOfTapsRequired = 1;
}
check view.gestureRecognizers here
- (void)handleSingleTap:(UIGestureRecognizer *)gestureRecognizer
{
UIEvent *event = [[UIEvent alloc] init];
CGPoint location = [gestureRecognizer locationInView:self.view];
//check actually view you hit via hitTest
UIView *view = [self.view hitTest:location withEvent:event];
if ([view.gestureRecognizers containsObject:gestureRecognizer]) {
//your UIView
//do something
}
else {
//your UITableView or some thing else...
//ignore
}
}
I created a UIGestureRecognizer subclass designed for blocking all gesture recognizers attached to a superviews of a specific view.
It's part of my WEPopover project. You can find it here.
implement a delegate for all the recognizers of the parentView and put the gestureRecognizer method in the delegate that is responsible for simultaneous triggering of recognizers:
func gestureRecognizer(UIGestureRecognizer, shouldBeRequiredToFailByGestureRecognizer:UIGestureRecognizer) -> Bool {
if (otherGestureRecognizer.view.isDescendantOfView(gestureRecognizer.view)) {
return true
} else {
return false
}
}
U can use the fail methods if u want to make the children be triggered but not the parent recognizers:
https://developer.apple.com/reference/uikit/uigesturerecognizerdelegate
I was also doing a popover and this is how I did it
func didTap(sender: UITapGestureRecognizer) {
let tapLocation = sender.locationInView(tableView)
if let _ = tableView.indexPathForRowAtPoint(tapLocation) {
sender.cancelsTouchesInView = false
}
else {
delegate?.menuDimissed()
}
}
You can turn it off and on.... in my code i did something like this as i needed to turn it off when the keyboard was not showing, you can apply it to your situation:
call this is viewdidload etc:
NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
[center addObserver:self selector:#selector(notifyShowKeyboard:) name:UIKeyboardDidShowNotification object:nil];
[center addObserver:self selector:#selector(notifyHideKeyboard:) name:UIKeyboardWillHideNotification object:nil];
then create the two methods:
-(void) notifyShowKeyboard:(NSNotification *)inNotification
{
tap.enabled=true; // turn the gesture on
}
-(void) notifyHideKeyboard:(NSNotification *)inNotification
{
tap.enabled=false; //turn the gesture off so it wont consume the touch event
}
What this does is disables the tap. I had to turn tap into a instance variable and release it in dealloc though.
Is it ok to override -handlePan: in a UIScrollView subclass?
i.e. my app won't get rejected from the app store?
Thanks for sharing your views.
Edit: what about calling -handlePan: in another method of my subclass?
In case anyone is interested, what I did instead of overriding was disabling the default UIPanGestureRecognizer and adding another instance of UIPanGestureRecognizer which is mapped to my custom handler.
Edit for twerdster:
I did it like this
//disables the built-in pan gesture
for (UIGestureRecognizer *gesture in scrollView.gestureRecognizers){
if ([gesture isKindOfClass:[UIPanGestureRecognizer class]]){
gesture.enabled = NO;
}
}
//add your own
UIPanGestureRecognizer *myPan = [[UIPanGestureRecognizer alloc] init...];
//customize myPan here
[scrollView addGestureRecognizer:myPan];
[myPan release];
You can make the code even shorter.
//disables the built-in pan gesture
scrollView.panGestureRecognizer.enabled = NO;
//add your own
UIPanGestureRecognizer *myPan = [[UIPanGestureRecognizer alloc] init...];
[scrollView addGestureRecognizer:myPan];
[myPan release];