I've googled on how to dismiss keyboard when touching a blank area in UITableView in iOS, and there're several ways to solve this. Like using delegate, UITapGestureRecognizer, - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event and - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event.
I decide to take hitTest by subclassing the corresponding UIView class and override this method like this:
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *result = [super hitTest:point withEvent:event];
[self endEditing:YES];
return result;
}
This really works, will dismiss the virtual keyboard when I touch / scroll / swipe / pinch ... somewhere else, but another problem shows up.
The keyboard is active or shown when I touch one UITextField object, then I touch the same UITextField object, here is the problem, the keyboard try to dismiss but not completely, in the middle of somewhere it begin to show up, doing this kind of weird animation. Most of the case in our APPs, the keyboard should stay still when we touch the same UITextField object. Is there a nice and simple way to solve this problem?
Solved:
Finally, I figure it out myself. Thanks to #Wain, thanks to #Wain's hint. I do check the result before I invoke [self endEditing:YES];. Here is the modified code:
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *result = [super hitTest:point withEvent:event];
// You can change the following condition to meet your own needs
if (![result isMemberOfClass:[UITextField class]] && ![result isMemberOfClass:[UITextView class]]) {
[self endEditing:YES];
}
return result;
}
As per #iBCode answer, if I select same text field multiple times then keyboard automatically hide and show immediately, to avoid that I have added one more condition and added code below in swift languagge
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
if let resultView = super.hitTest(point, with: event) {
if resultView.isMember(of: UITextField.self) ||
resultView.isKind(of: UITextField.self) ||
resultView.isMember(of: UITextView.self) ||
resultView.isKind(of: UITextView.self) {
return resultView
}
if !resultView.isMember(of: UITextField.self) && !resultView.isMember(of: UITextView.self) {
endEditing(true)
}
return resultView
}
return nil
}
Check the class of the result so that you can limit when you end editing. If the hit target was an editable class (like a text field, or a switch) then don't end the editing session.
I have a custom subclass of MKPinAnnotationView that displays a custom call out. I want to handle touch events inside that annotation.
I have a working solution (below) but it just doesn't feel right. I have a rule of thumb that whenever I use performSelector: .. withDelay: I'm fighting the system rather than working with it.
Does anyone have a good, clean workaround for the aggressive event handling of MKMapView and annotation selection handling?
My current solution:
(All code from my annotation selection class)
I do my own hit testing (without this my gesture recognisers don't fire as the Map View consumes the events:
- (UIView*)hitTest:(CGPoint)point withEvent:(UIEvent*)event; {
// To enable our gesture recogniser to fire. we have to hit test and return the correct view for events inside the callout.
UIView* hitView = nil;
if (self.selected) {
// check if we tpped inside the custom view
if (CGRectContainsPoint(self.customView.frame, point))
hitView = self.customView;
}
if(hitView) {
// If we are performing a gesture recogniser (and hence want to consume the action)
// we need to turn off selections for the annotation temporarily
// the are re-enabled in the gesture recogniser.
self.selectionEnabled = NO;
// *1* The re-enable selection a moment later
[self performSelector:#selector(enableAnnotationSelection) withObject:nil afterDelay:kAnnotationSelectionDelay];
} else {
// We didn't hit test so pass up the chain.
hitView = [super hitTest:point withEvent:event];
}
return hitView;
}
Note that I also turn off selections so that in my overridden setSelected I can ignore the deselection.
- (void)setSelected:(BOOL)selected animated:(BOOL)animated; {
// If we have hit tested positive for one of our views with a gesture recogniser, temporarily
// disable selections through _selectionEnabled
if(!_selectionEnabled){
// Note that from here one, we are out of sync with the enclosing map view
// we're just displaying out callout even though it thinks we've been deselected
return;
}
if(selected) {
// deleted code to set up view here
[self addSubview:_customView];
_mainTapGestureRecogniser = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(calloutTapped:)];
[_customView addGestureRecognizer: _mainTapGestureRecogniser];
} else {
self.selected = NO;
[_customView removeFromSuperview];
}
}
It's the line commented 1 that I don't like but it's also pretty hairy at the end of theta delayed fire. I have to walk back up the superview chain to get to the mapView so that I can convince it the selection is still in place.
// Locate the mapview so that we can ensure it has the correct annotation selection state after we have ignored selections.
- (void)enableAnnotationSelection {
// This reenables the seelction state and resets the parent map view's idea of the
// correct selection i.e. us.
MKMapView* map = [self findMapView];
[map selectAnnotation:self.annotation animated:NO];
_selectionEnabled = YES;
}
with
-(MKMapView*)findMapView; {
UIView* view = [self superview];
while(!_mapView) {
if([view isKindOfClass:[MKMapView class]]) {
_mapView = (MKMapView*)view;
} else if ([view isKindOfClass:[UIWindow class]]){
return nil;
} else{
view = [view superview];
if(!view)
return nil;
}
}
return _mapView;
}
This all seems to work without and downside (like flicker I've seen from other solutions. It's relatively straightforward but it doesn't feel right.
Anyone have a better solution?
I don't think you need to monkey with the map view's selection tracking. If I'm correctly interpreting what you want, you should be able to accomplish it with just the hitTest:withEvent: override and canShowCallout set to NO. In setSelected: perform your callout appearance/disappearance animation accordingly. You should also override setHighlighted: and adjust the display of your custom callout if visible.
I'm trying to override hitTest:withEvent in a custom view. This is a container view with many subviews.
Attached to this "superView" is a gesture recognizer. On top of this view sit many subviews (which in turn have more and more subviews) I decided to over ride hitTesh:withEvent in order to decide which view should get the events - and in which cases the superview should get the event in order to trigger the gesture.
Problem I am having is that hitTest will return the superview in cases where a tap gesture would be initialized in a subview. In that case I would like to "retroactively" disregard the tap action - and again "invoke" hitTest:withEvent on the superview. the superview could then decide to pass the "true" responder to this event.
How can I do it:
Example:
// In the container view
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
// the default view that would have been returned
UIView *v = [super hitTest:point withEvent:event];
// if nil than touch wasn't in this view so disregard
if (v == nil)
{
return nil;
}
// if the touch was on a control than I don't want to take care of it
if ([v isKindOfClass:[UIControl Class]])
{
return v;
}
// now here is where I need to fix
// I am only interested in a touch event that would initiated a pan gesture
// if the event was a tap for intance - than return [super hitTest:point withEvent:event]
// for instance if a uitableview cell was tapped - I don't want to mask the event
if (event wouldn't initiate a pan)
{
return v;
}
return self;
}
I have a clear UIView which has gesture recognizers attached to it.
This clear uiview covers the entire super view to allow for the gestures to be invoked from anywhere on it.
Under this clear UIView sit different components such as tables,buttons,collectionview etc.
The clear UIView has no idea what is under it any time.
What I want - if a view which is under the clear uiview can handle a touch event (or any type of gesture) - the clear view should disregard that event - and the event will pass through to the underlying view which could handle it.
I tried
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
but I don't know how to make sure the underlying view can handle it.
-(id)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
id hitView = [super hitTest:point withEvent:event];
if (hitView == self)
{
return nil;
}
else
{
return hitView;
}
}
Add this to your to clear view.
If the hit on clear view means just return nil.
You can override pointInside: withEvent: method. This method returns a boolean value indicating whether the receiver contains the specified point. So if we return NO then your upper clear view will become transparent for touch events and they will be passed to underlying views.
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {
// Clear UIView will now respond to touch events if return NO:
return NO;
}
use below code for your case->
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event{
UIView *hitTestView = [super hitTest:point withEvent:event];
if(hitTestView!=nil){
//check for gesture
if([hitTestView.gestureRecognizers count]>0)
return hitTestView;
//if it is subclass of UIControl like UIButton etc
else if([hitTestView isKindOfClass:[UIControl class]])
return hitTestView;
//if can handle touches
else if([hitTestView respondsToSelector:#selector(touchesBegan:withEvent:)])
return hitTestView;
else
return nil;
}
else{
return self;
}
}
In the above code if the subView which is hitView can anyway handle touch ,we return that object to handle that touch. If there is no such hitTest view, then we return the view itself.
I used some of these suggestions and used the following solution:
I added the gesture recognizer to the bottom most superview in the heirarchy (and not the top most)
Then in that class over rid
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *v = [super hitTest:point withEvent:event];
// if v is nil then touch wasn't in this view or its subviews
if (v == nil)
{
return nil;
}
// in any case if the topview was hidden than return the default value
if (self.myTopView.hidden)
{
return v;
}
// if the view isn't hidden but the touch returned a control - than we can pass the touch to the control
if ([v isKindOfClass:[UIControl class]])
{
return v;
}
// decide on what threshold to decide is a touch
CGFloat threshHold = 40;
// if the touch wasn't on a control but could initiate a gesture than that view should get the touch
if (v.gestureRecognizers)
{
threshHold = 30;
// return v;
}
// check if the threshold should be bigger
if ([self someCondition])
{
threshHold = 100;
}
// threshold according to its position - this is the dynamic part
if (point.y > (self.myTopView.frame.origin.y - threshold))
{
return self.handleBarView;
}
return v;
}
The following code expresses my problem:
(It's self-contained in that you could create a Xcode project with an empty template, replace the contents of the main.m file, delete the AppDelegate.h/.m files and build it)
//
// main.m
// CollectionViewProblem
//
#import <UIKit/UIKit.h>
#interface Cell : UICollectionViewCell
#property (nonatomic, strong) UIButton *button;
#property (nonatomic, strong) UILabel *label;
#end
#implementation Cell
- (id)initWithFrame:(CGRect)frame
{
if (self = [super initWithFrame:frame])
{
self.label = [[UILabel alloc] initWithFrame:self.bounds];
self.label.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
self.label.backgroundColor = [UIColor greenColor];
self.label.textAlignment = NSTextAlignmentCenter;
self.button = [UIButton buttonWithType:UIButtonTypeInfoLight];
self.button.frame = CGRectMake(-frame.size.width/4, -frame.size.width/4, frame.size.width/2, frame.size.width/2);
self.button.backgroundColor = [UIColor redColor];
[self.button addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.contentView addSubview:self.label];
[self.contentView addSubview:self.button];
}
return self;
}
// Overriding this because the button's rect is partially outside the parent-view's bounds:
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
if ([super pointInside:point withEvent:event])
{
NSLog(#"inside cell");
return YES;
}
if ([self.button
pointInside:[self convertPoint:point
toView:self.button] withEvent:nil])
{
NSLog(#"inside button");
return YES;
}
return NO;
}
- (void)buttonClicked:(UIButton *)sender
{
NSLog(#"button clicked!");
}
#end
#interface ViewController : UICollectionViewController
#end
#implementation ViewController
// (1a) viewdidLoad:
- (void)viewDidLoad
{
[super viewDidLoad];
[self.collectionView registerClass:[Cell class] forCellWithReuseIdentifier:#"ID"];
}
// collection view data source methods ////////////////////////////////////
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
return 100;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
Cell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"ID" forIndexPath:indexPath];
cell.label.text = [NSString stringWithFormat:#"%d", indexPath.row];
return cell;
}
///////////////////////////////////////////////////////////////////////////
// collection view delegate methods ////////////////////////////////////////
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
NSLog(#"cell #%d was selected", indexPath.row);
}
////////////////////////////////////////////////////////////////////////////
#end
#interface AppDelegate : UIResponder <UIApplicationDelegate>
#property (strong, nonatomic) UIWindow *window;
#end
#implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
ViewController *vc = [[ViewController alloc] initWithCollectionViewLayout:layout];
layout.itemSize = CGSizeMake(128, 128);
layout.minimumInteritemSpacing = 64;
layout.minimumLineSpacing = 64;
layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
layout.sectionInset = UIEdgeInsetsMake(32, 32, 32, 32);
self.window.rootViewController = vc;
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
#end
int main(int argc, char *argv[])
{
#autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
}
Basically I'm creating a Springboard-type UI using collection views. My UICollectionViewCell subclass (Cell) has a button which lies partially outside the cell's contentView (i.e. its superview's) bounds.
The problem is that clicking on any part of the button outside of the contentView bounds (basically 3/4th of the button) doesn't invoke the button action. Only when clicking on the portion of the button that overlaps the contentView is the button's action method called.
I've even overridden -pointInside:withEvent: method in Cell so that touches in the button will be acknowledged. But that hasn't helped with the button clicking problem.
I'm guessing it might be something to do with how collectionView handles touches, but I don't know what. I know that UICollectionView is a UIScrollView subclass and I've actually tested that overriding -pointInside:withEvent: on a view (made subview to a scroll view) containing a partially overlapping button solves the button clicking problem, but it hasn't worked here.
Any help?
** Added:
For the record, my current solution to the problem involves insetting a smaller subview to contentView which gives the cell its appearance. The delete button is added to the contentView such that its rect actually lies within the bounds of contentView but only partially overlaps the visible part of the cell (i.e. the inset subview). So I've got the effect I wanted, and the button is working properly. But I'm still curious about the problem with the original implementation above.
The problem appears to be with hitTest/pointInside. I'm guessing the cell is returning NO from pointInside if the touch is on the part of the button that is outside the cell and thus the button doesn't get hit tested. To fix this you have to override pointInside on your UICollectionViewCell subclass to take the button into account. You also need to override hitTest to return the button if the touch is inside the button. Here are example implementations assuming your button is in a property in the UICollectionViewCell subclass called deleteButton.
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
UIView *view = [self.deleteButton hitTest:[self.deleteButton convertPoint:point fromView:self] withEvent:event];
if (view == nil) {
view = [super hitTest:point withEvent:event];
}
return view;
}
-(BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {
if ([super pointInside:point withEvent:event]) {
return YES;
}
//Check to see if it is within the delete button
return !self.deleteButton.hidden && [self.deleteButton pointInside:[self.deleteButton convertPoint:point fromView:self] withEvent:event];
}
Note that because hitTest and pointInside expect the point to be in the coordinate space of the receiver you have to remember to convert the point before calling those methods on the button.
In Interface Builder do you have set the object as UICollectionViewCell? Because erroneously one time I set a UIView and after assign to it the correct UICollectionViewCell class...but doing this things (buttons, labels, ecc.) are not added tor the contentView so they don't respond as they would...
So, remind in IB to take the UICollectionViewCell Object when drawing the interface :)
Swift version:
override func hitTest(point: CGPoint, withEvent event: UIEvent?) -> UIView? {
//From higher z- order to lower except base view;
for (var i = subviews.count-2; i >= 0 ; i--){
let newPoint = subviews[i].convertPoint(point, fromView: self)
let view = subviews[i].hitTest(newPoint, withEvent: event)
if view != nil{
return view
}
}
return super.hitTest(point, withEvent: event)
}
that's it ... for all subViews
I am successfully receiving touches to a button created as follows in the subclassed UICollectionViewCell.m file;
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self)
{
// Create button
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0, 0, 100, 100); // position in the parent view and set the size of the button
[button setTitle:#"Title" forState:UIControlStateNormal];
[button setImage:[UIImage imageNamed:#"animage.png"] forState:UIControlStateNormal];
[button addTarget:self action:#selector(button:) forControlEvents:UIControlEventTouchUpInside];
// add to contentView
[self.contentView addSubview:button];
}
return self;
}
I added the button in code after realising that buttons added in Storyboard did not work, not sure if this is fixed in latest Xcode.
Hope that helps.
I see two swift conversions of the original answer that aren't exactly swift conversions. So I just want to give the Swift 4 conversion of the original answer so everyone who wants to can use it. You can just paste the code into your subclassed UICollectionViewCell. Just make sure that you change closeButton with your own button.
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
var view = closeButton.hitTest(closeButton.convert(point, from: self), with: event)
if view == nil {
view = super.hitTest(point, with: event)
}
return view
}
override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
if super.point(inside: point, with: event) {
return true
}
return !closeButton.isHidden && closeButton.point(inside: closeButton.convert(point, from: self), with: event)
}
As accepted answer requested, we should make a hitTest in order to recieve touches inside the cell. Here is the Swift 4 code for hit test:
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
for i in (0..<subviews.count-1).reversed() {
let newPoint = subviews[i].convert(point, from: self)
if let view = subviews[i].hitTest(newPoint, with: event) {
return view
}
}
return super.hitTest(point, with: event)
}
I had a similar problem trying to place a deletion button outside the bounds of a uicollectionview cell and it didn't seam to respond to tap events.
the way i solved it was to place a UITapGestureRecognizer on the collection and when a tap happend preform the following code
//this works also on taps outside the cell bouns, im guessing by getting the closest cell to the point of click.
NSIndexPath* tappedCellPath = [self.collectionView indexPathForItemAtPoint:[tapRecognizer locationInView:self.collectionView]];
if(tappedCellPath) {
UICollectionViewCell *tappedCell = [self.collectionView cellForItemAtIndexPath:tappedCellPath];
CGPoint tapInCellPoint = [tapRecognizer locationInView:tappedCell];
//if the tap was outside of the cell bounds then its in negative values and it means the delete button was tapped
if (tapInCellPoint.x < 0) [self deleteCell:tappedCell];
}
Honus has the best answer here in my opinion. In fact the only one that worked for me so I've been answering other similar questions and sending them this way:
I spent hours scouring the web for a solution to my UIButton's inside UICollectionView's not working. Driving me nuts until I finally found a solution that works for me. And I believe it's also the proper way to go: hacking the hit tests. It's a solution that can go a lot deeper (pun intended) than fixing the UICollectionView Button issues as well, as it can help you get the click event to any button buried under other views that are blocking your events from getting through:
UIButton in cell in collection view not receiving touch up inside event
Since that SO answer was in Objective C, I followed the clues from there to find a swift solution:
http://khanlou.com/2018/09/hacking-hit-tests/
--
When I would disable user interaction on the cell, or any other variety of answers I tried, nothing worked.
The beauty of the solution I posted above is that you can leave your addTarget's and selector functions how you are used to doing them since they were most likey never the problem. You need only override one function to help the touch event make it to its destination.
Why the solution works:
For the first few hours I figured the gesture wasn't being registered properly with my addTarget calls. It turns out the targets were registering fine. The touch events were simply never reaching my buttons.
The reality seems to be from any number of SO posts and articles I read, that UICollectionView Cells were meant to house one action, not multiple for a variety of reasons. So you were only supposed to be using the built in selection actions. With that in mind, I believe the proper way around this limitation is not to hack UICollectionView to disable certain aspects of scrolling or user interaction. UICollectionView is only doing its job. The proper way is to hack the hit tests to intercept the tap before it gets to UICollectionView and figure out which items they were tapping on. Then you simply send a touch event to the button they were tapping on, and let your normal stuff do the work.
My final solution (from the khanlou.com article) is to put my addTarget declaration and my selector function wherever I like (in the cell class or the cellForItemAt override), and in the cell class overriding the hitTest function.
In my cell class I have:
#objc func didTapMyButton(sender:UIButton!) {
print("Tapped it!")
}
and
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
guard isUserInteractionEnabled else { return nil }
guard !isHidden else { return nil }
guard alpha >= 0.01 else { return nil }
guard self.point(inside: point, with: event) else { return nil }
// add one of these blocks for each button in our collection view cell we want to actually work
if self.myButton.point(inside: convert(point, to: myButton), with: event) {
return self.myButton
}
return super.hitTest(point, with: event)
}
And in my cell class init I have:
self.myButton.addTarget(self, action: #selector(didTapMyButton), for: .touchUpInside)
I found this from here py4u.net
tried the solution that was at the very bottom. (the whole stuff was collected from this page, as I understand)
In my case the colution also worked. and then I just checked wether the User Interaction Enabled checkmark is checked on Collection view in xib and in it's contentView. Guess what. the contentView`s UserInteraction was disabled.
Enabling it fixed the issue with button's touchUpInside event and there was no need to override hitTest method.
You might not have to override hit test or do any of the complicated solutions above.
This issue can also be caused if you are using a custom button with lots of subviews.
What happens is when the button is hit tested, one of its subviews is being returned.
A cleaner solution here is just to set userInteractionEnabled = false on all of your button's subviews.
That way, hit testing your button will only ever return the button itself and none of the views on it.