I currently have a setup of:
A RootVC, with a UIPanGestureRecognizer on self.view. Then the RootVC has a child UITableViewController and hence UITableViewController.view is a subview of self.view.
The cells on the UITableViewController also have gesture recognizers enabling them to be swiped sideways. This works perfectly when the UITableViewController is itself the root view controller.
My issue is that im trying to pass a specific gesture from the self.view gesture recognizer down to the table cells. I've tried delegates:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
and
-(BOOL)gestureRecognizerShouldBegin:(UIPanGestureRecognizer *)gestureRecognizer
I can correctly identify the gestures i want to be sent below and return NO in that instance but that seems to cancel the gesture instead of passing it to subviews.
I know i could just call
[self.view.subviews[0] gestureShouldBegin:gestureRecognizer];
But because its the table view cells i cannot determine which cell the gesture should be sent too.
I have been thinking something like
[[self.childViewControllers[0] cellForRowAtIndexPath:indexPath] gestureShouldBegin:gestureRecognizer];
Would work but i dont know how to determine the correct indexPath..
Any ideas?
Look at (NSIndexPath *)indexPathForRowAtPoint:(CGPoint)point
You'll need to translate the point of the gesture to the coordinates for the tableView first.
Related
I have a table view with a pan gesture on it. When I start panning the tableview up and down the tableView selection gets disable and I can't select tableview cells.
UIPanGesture* tablePanGesture =[[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(gestureHandler:)];
tablePanGesture.delegate = self;
[tableView addGestureRecognizer:tablePanGesture];
[tablePanGesture setCancelsTouchesInView:NO];
And I using the following delegate to let my gestures and tableview gestures work together:
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
return YES;
}
I have implemented the method for table view didSelectRowAtIndexPath but when I use panning it is not called.
Is there any conflict between pan gesture and tableview Delegate?
You are missing this line:-
[tablePanGesture setCancelsTouchesInView:NO];
This will let the UIPanGesture recognize the pan gesture and also pass the touch to the next responder means your table view select or tap.
I have a view which looks like this:
I implemented this view with two horizontal uitableview. So all promotions under certain category actually is in a table view which allow user to swipe left and right to change category. On the left top there is a button which opens a side view. Now I want to add a screen edge gesture to open the side view but it seems the screen edge gesture conflicts with the table view scrolling gesture.
So where should I do if I want to implement the screen edge gesture without disabling tableview's scroll gesture?
Thanks!
Set your gesture delegate in your viewcontroller class, and use this delegate method :
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES ;
}
Brief
I am having an issue with a UITableView inside a UIScrollView. When I scroll the external scrollView, the table does not receive the willSelect/didSelect event on the first touch, but it does on the second one. What is even more strange, the cell itself gets the touches and the highlighted state, even when the delegate does not.
Detailed explanation
My view hierarchy:
UIView
- UIScrollView (outerscroll)
- Some other views and buttons
- UITableView (tableView)
Inside the scroll view I have some extra views that get expanded/closed dynamically. The table view needs to get "fixed" on top, together with some other elements of the view, so that is why I created this layout, that allows me to easily move elements in a similar way than Apple recommends by the use of transformations when the scroll happens.
The table View is transformed with a translation effect when the outerscroll moves like this:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
if (scrollView == self.outerScrollView) {
CGFloat tableOffset = scrollView.contentOffset.y - self.fixedHeaderFrame.origin.y;
if (tableOffset > 0) {
self.tableView.contentOffset = CGPointMake(0, tableOffset);
self.tableView.transform = CGAffineTransformMakeTranslation(0, tableOffset);
}
else {
self.tableView.contentOffset = CGPointMake(0, 0);
self.tableView.transform = CGAffineTransformIdentity;
}
// Other similar transformations are done here, but not involving the table
}
In my cell, if I implement these methods:
- (void)setSelected:(BOOL)selected {
[super setSelected:selected];
if (selected) {
NSLog(#"selected");
}
}
- (void)setHighlighted:(BOOL)highlighted animated:(BOOL)animated
{
[super setHighlighted:highlighted animated:animated];
if (highlighted) {
NSLog(#"highlighted");
}
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
NSLog(#"touchesBegan");
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
NSLog(#"touchesEnded");
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesCancelled:touches withEvent:event];
NSLog(#"touchesCancelled");
}
Y can see this output when fails (first tap):
2014-02-10 13:04:40.940 MyOrderApp[5588:70b] highlighted
2014-02-10 13:04:40.940 MyOrderApp[5588:70b] touchesBegan
2014-02-10 13:04:40.978 MyOrderApp[5588:70b] touchesEnded
And this one when works (second tap):
2014-02-10 13:05:30.359 MyOrderApp[5588:70b] highlighted
2014-02-10 13:05:30.360 MyOrderApp[5588:70b] touchesBegan
2014-02-10 13:05:30.487 MyOrderApp[5588:70b] touchesEnded
2014-02-10 13:05:30.498 MyOrderApp[5588:70b] expanded
No other frame change, animation or any other view interaction is done between the first and the second tap. Also, only when scrolling large amounts the bug appears, but with scrollings of just a few pixels everything keeps working as expected.
I experimented changing some properties as well, but with no luck. Some of the things I did:
Remove userInteractionEnabled from views other than the scroll and table
Add a call to setNeedsLayout on the table, scroll and main view when scrollViewDidScroll occurs.
Remove the transformations from the table (still happens)
I have seen some comments about the unexpected behaviour of embedding UITableViews inside UIScrollViews but I can not see such a warn in the official documentation by Apple, so I am expecting it to work.
The app is iOS7+ only.
Questions
Has anyone experienced similar issues? Why is this and how can I solve it? I think that I could be able to intercept the tap gesture on the cell and pass it with a custom delegate or similar, but I would like the table to receive the proper events and so my UITableViewDelegate receives it as expected.
Updates
I tried disabling cell reuse as suggested in a comment but it still happens in the same way.
leave the inner UITableView's scrollEnabled property set as YES. this lets the inner UITableView know to handle scroll-related touches on the UIScrollView correctly.
From Apple Documentation, you shouldn't embed a UITableViewinside a UIScrollView.
Important: You should not embed UIWebView or UITableView objects in
UIScrollView objects. If you do so, unexpected behavior can result
because touch events for the two objects can be mixed up and wrongly
handled.
Your problem is really related to what your UIScrollView does.
But if it's just to hide the tableview when needed (that was my case), you can just move the UITableView in its superview.
I wrote a small example here : https://github.com/rvirin/SoundCloud/
I ran into this same problem and figured out a solution!!
You need to set the delaysTouchesBegan to true on your scrollview so that the scrollview sends its failed scrolled-gesture (i.e. the tap) to its children.
var delaysTouchesBegan: Bool -
A Boolean value determining whether the receiver delays sending touches in a begin phase to its view.
When the value of the property is YES, the window suspends delivery of
touch objects in the UITouchPhaseBegan phase to the view. If the
gesture recognizer subsequently recognizes its gesture, these touch
objects are discarded. If the gesture recognizer, however, does not
recognize its gesture, the window delivers these objects to the view
in a touchesBegan:withEvent: message (and possibly a follow-up
touchesMoved:withEvent: message to inform it of the touches’ current
locations).
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIGestureRecognizer_Class/index.html#//apple_ref/occ/instp/UIGestureRecognizer/delaysTouchesBegan
But there's a catch...it doesn't work if you do it directly on the scrollview!
// Does NOT work
self.myScrollview.delaysTouchesBegan = true
Apparently this is an iOS bug where setting this property doesn't work (thank you apple). However there's a simple workaround: set the property directly on the scrollview's pan gesture. Sure enough, this worked for me perfectly:
// This works!!
self.myScrollview.panGestureRecognizer.delaysTouchesBegan = true
It seems that your UiTableView doesn't recognize your tap. Did you try to use that :
- (BOOL)gestureRecognizer:(UIPanGestureRecognizer *)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:(UISwipeGestureRecognizer *)otherGestureRecognizer
{
if ([otherGestureRecognizer.view isKindOfClass:[UITableView class]]) {
return YES;
}
return NO;
}
Note from apple:
called when the recognition of one of gestureRecognizer or otherGestureRecognizer would be blocked by the other. return YES to allow both to recognize simultaneously. the default implementation returns NO (by default no two gestures can be recognized simultaneously)
note: returning YES is guaranteed to allow simultaneous recognition. returning NO is not guaranteed to prevent simultaneous recognition, as the other gesture's delegate may return YES
Hope that will help.
Gesture recognizers won't work correctly for two embedded scroll views or subclasses.
Try a workaround:
Use transparent, custom, and overlaying everything in cell UIButton with proper tag, or subclass UIButton and add a index path property and overwrite each time in reused cell.
Add this button as a property to your custom cell.
Add target for desired UIControlEvent (one or more) that points to your UITableViewDelegate protocol adopting class.
Disable selecting in IB, and manually manage the selection from code.
This solution requires attention for cases of single/multi selection.
I've encountered a UITableView with scrollEnabled being NO within a UIScrollView in some legacy code. I have not been able to change the existing hierarchy easily nor enable scrolling, but come up with the the following workaround for the first tap problem:
#interface YourOwnTableView : UITableView
#end
#implementation YourOwnTableView
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesCancelled:touches withEvent:event];
// Note that this is a hack and it can stop working at some point.
// Looks like a table view with scrollEnabled being NO does not handle cancellation cleanly,
// so let's repeat begin/end touch sequence here hoping it'll reset its own internal state properly
// but won't trigger cell selection (the touch passed is in its cancelled phase, perhaps there is a part
// of code inside which actually checks it)
[super touchesBegan:touches withEvent:event];
[super touchesEnded:touches withEvent:event];
}
#end
Again, this is just a workaround working in my specific case. Having a table view within a scroll view is still a wrong thing.
I would recommend to look for options like not letting your cell to be in highlighted state when you are actually scrolling the outer scroll view which is very easy to handle and is the recommended way. You can do this just by taking a boolean and toggling it in the below method
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
The scrollview is trying to figure out whether the user's intention is to scroll or not, so it's delaying the initial touch on purpose. You can turn this off by setting delaysContentTouches to NO.
I have the same problem with nested UITableView and have found a work-around for this:
innerTableView.scrollEnabled = YES;
innerTableView.alwaysBounceVertical = NO;
You'll need to set the height of the inner table view to match with the total height of its cells so that it'll not scroll when user scrolling the outer view.
Hope this helps.
My mistake was implementing the delegate method:
- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
instead of the one I meant to implement:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
Hence only being called on the second cell being tapped, because that was when the first cell would be de selected. Stupid mistake made with the help of autocomplete. Just a thought for those of you who may wander here not realizing you've made the same mistake too.
Drop a UIButton over your UITableViewCell and create the outlet as "btnRowSelect".
In your view controller put this code in cellForRowAtIndexPath
cell.btnRowSelect.tag = indexPath.row
cell.btnRowSelect.addTarget(self, action: Selector("rowSelect:"), forControlEvents: .TouchUpInside)
Add this function to your viewController as well-
func rowSelect (sender:UIButton) {
// "sendet.tag" give you the selected row
// do whatever you want to do in didSelectRowAtIndexPath
}
This function "rowSelect" will work as didSelectRowAtIndexPath where
you get the row"indexPath.row" as "sender.tag"
As other answers say you shouldn't put a tableview in a scrollview. A UITableView inherits from UIScrollView anyway so I guess that's where things get confusing. What I always do in this situation is:
1) Subclass UITableViewController and include a property UIView *headView.
2) In the parent UIViewController create all the top stuff in a container UIView
3) Initialise your custom UITableView and add the tableView's view to the view controller full size
[self.view addSubview: self.myTableView.view];
4) Set the headView to be your UIView gubbins
self.tableView.headView = myHeadViewGubbins.
5) In the tableViewController method
-(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger *)section;
Do:
if ( section == 0 ) {
return self.headView;
}
Now you have a table view with a bunch of other shizzle at the top.
Enjoy!
That it, if touch table view it will work properly. also with scroll view in same view controller also.
tableview.scrollEnabled = true;
I have the same issue, Then refer to "Nesting Scroll Views" as lxx said.
https://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/UIScrollView_pg/NestedScrollViews/NestedScrollViews.html
An example of cross directional scrolling can be found in the Stocks application. The top view is a table view, but the bottom view is a horizontal scroll view configured using paging mode. While two of its three subviews are custom views, the third view (that contains the news articles) is a UITableView (a subclass of UIScrollView) that is a subview of the horizontal scroll view. After you scroll horizontally to the news view, you can then scroll its contents vertically.
It is work
UITapGestureRecognizer is applied to both UIImageView and its subview (UITextView). However, when I tap on subview, the receiver becomes subview and its parent view (i.e. UIImageView + UITextView). It should however be only subview because that was the one I tapped. I was assuming nested gestures would react first but apparently parent receives the fist tap and then it goes to child.
So, there are different solutions out there for various scenarios (not similar to mine but rather buttons inside scroll view conflict). How can I easily fix my issue without possible subclassing and for iOS 6+ support? I tried delaying touch on start for UIGestureRecognizer on UIImageView and I tried setting cancelsTouchesInView to NO - all with no luck.
Try the following code:
conform the <UIGestureRecognizerDelegate> to your class.
set yourGesture.delegate = self;
then add this delegate Method:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
// return YES (the default) to allow the gesture recognizer to examine the touch object, NO to prevent the gesture recognizer from seeing this touch object.
if([touch.view isKindOfClass: [UITextView class]] == YES)] {
return YES;
}
else {
return NO;
}
}
Hope it will solve your issue. Enjoy Coding..!!!!
That's exactly what is it supposed to do.
View hierarchy is like a tree structure and its traversal during a touch gesture starts from the root node. It is very likely for your parent view to receive gesture first and then its subviews. The traversal skips the nodes for which
userInteractionEnabled = NO.
since, you don't have any code I can't help you to play with this flag. A more general solution is to always set gesture only for your parentView and in the gesture delegates check the coordinates if it belongs to any one of the subview and if yes then call your gesture method for your subview.
Not a clean approach but works. !!
you should implement the UIGestureRecognizer delegate methods and apply the correct policy to the gesture, when multiple gesture are recognized
Here's how the scroll views work: One scroll view is paging enabled in the horizontal direction. Each 'page' of this scroll view contains a vertically scrolling UITableView. Without modification, this works OK, but not perfectly.
The behaviour that's not right: When the user scrolls up and down on the table view, but then wants to flick over to the next page quickly, the horizontal flick/swipe will not work initially - it will not work until the table view is stationary (even if the swipe is very clearly horizontal).
How it should work: If the swipe is clearly horizontal, I'd like the page to change even if the table view is still scrolling/bouncing, as this is what the user will expect too.
How can I change this behaviour - what's the easiest or best way?
NOTE For various reasons, a UIPageViewController as stated in some answers will not work. How can I do this with cross directional UIScrollViews (/one is a table view, but you get the idea)? I've been banging my head against a wall for hours - if you think you can do this then I'll more than happily award a bounty.
According to my understanding of the question, it is only while the tableView is scrolling we want to change the default behaviour. All the other behaviour will be the same.
SubClass UITableView. UITableViews are subClass of UIScrollViews. On the UITableView subClass implement one UIScrollView's UIGestureRecognizer's delegate method
- (BOOL)gestureRecognizer:(UIPanGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UISwipeGestureRecognizer *)otherGestureRecognizer
{
//Edit 1
//return self.isDecelerating;
//return self.isDecelerating | self.bounces; //If we want to simultaneous gesture on bounce and scrolling
//Edit 2
return self.isDecelerating || self.contentOffset.y < 0 || self.contentOffset.y > MAX(0, self.contentSize.height - self.bounds.size.height); // #Jordan edited - we don't need to always enable simultaneous gesture for bounce enabled tableViews
}
As we only want to change the default gesture behaviour while the tableView is decelerating.
Now change all 'UITableView's class to your newly created tableViewSubClass and run the project, swipe should work while tableView is scrolling. :]
But the swipe looks a little too sensitive while tableView is scrolling. Let's make the swipe a little restrictive.
SubClass UIScrollView. On the UIScrollView subclass implement another UIGestureRecognizer's delegate method gestureRecognizerShouldBegin:
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
CGPoint velocity = [(UIPanGestureRecognizer *)gestureRecognizer velocityInView:self];
if (abs(velocity.y) * 2 < abs(velocity.x)) {
return YES;
}
}
return NO;
}
We want to make the "swipe is clearly horizontal". Above code only permits gesture begin if the gesture velocity on x axis is double than on y axis. [Feel free to increase the hard coded value "2" if your like. The higher the value the swipe needs to be more horizontal.]
Now change the `UiScrollView' class (which has multiple TableViews) to your ScrollViewSubClass. Run the project. :]
I've made a project on gitHub https://github.com/rishi420/SwipeWhileScroll
Although apple doesn't like this method too much:
Important: You should not embed UIWebView or UITableView objects in UIScrollView objects. If you do so, unexpected behavior can result
because touch events for the two objects can be mixed up and wrongly
handled.
I've found a great way to accomplish this.
This is a complete solution for the problem. In order to scroll the UIScrollView while your UITableView is scrolling you'll need to disable the interaction you have it.
- (void)viewDidLoad
{
[super viewDidLoad];
_myScrollView.contentSize = CGSizeMake(2000, 0);
data = [[NSMutableArray alloc]init];
for(int i=0;i<30;i++)
{
[data addObject:[NSString stringWithFormat:#"%d",i]];
}
UITapGestureRecognizer * tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
[self.view addGestureRecognizer:tap];
}
- (void)handleTap:(UITapGestureRecognizer *)recognizer
{
[_myTableView setContentOffset:_myTableView.contentOffset animated:NO];
}
- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
{
scrollView.userInteractionEnabled = NO;
}
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
scrollView.userInteractionEnabled = YES;
}
To sum up the code above, if the UITableView is scrolling, set userInteractionEnabled to NO so the UIScrollView will detect the swipe. If the UITableView is scrolling and the user taps on the screen, userInteractionEnabled will be set to YES.
Instead of using UIScrollView as a container for these multiple table views, try using a UIPageViewController.
You can even integrate this into your existing view controller setup as a child view controller (directly replacing the UIScrollView).
In addition, you'll likely want to implement the required methods from UIPageViewControllerDataSource and possibly one or more of the methods from UIPageViewControllerDelegate.
Did you try the methods : directionalLockEnabled of both your table and scroll and set them up to horizontal for one and vertical for the other ?
Edit :
1)
What you want to do is very complicate since the touch wait some time (like 0.1s) to know what your movement will be. And if your table is moving, it will take your touch immediately whatever it is (because it's suppose to be reactive movement on it).
I don't see any other solution for you but to override touch movement from scratch to detect immediately the kind of mouvement you want (like if the movement will be horizontal) but it will be more than hard to do it good.
2)
Another solution I can advise you is to make your table have left and right margin, where you can touch the parent scroll (pages thing so) and then even if your table is scrolling, if you touch here, only your paging scroll will be touched. It's simpler, but could not fit with your design maybe...
Use UIPageViewController and in the -viewDidLoad method (or any other method what best suits your needs or design) get UIPageViewController's UIScrollView subview and assign a delegate to it. Keep in mind that, its delegate property won't be nil. So optionally, you can assign it to another reference, and then assign your object, which conforms to UIScrollViewDelegate, to it. For example:
id<UIScrollViewDelegate> originalPageScrollViewDelegate = ((UIScrollView *)[pageViewController.view.subviews objectAtIndex:0]).delegate;
[((UIScrollView *)[pageViewController.view.subviews objectAtIndex:0]) setDelegate:self];
So that you can implement UIScrollViewDelegate methods with ease. And your UIPageViewController will call your delegate's -scrollViewDidScroll: method.
By the way, you may be obliged to keep original delegate, and respond to delegate methods with that object. You can see an example implementation in ViewPagerController class on my UI control project here
I faced the same thing recently. My UIScrollview was on paging mode and every page contained a UITableView and like you described it worked but not as you'd expected it to work. This is how solved it.
First I disabled the scrolling of the UIScrollview
Then I added a UISwipeGestureRecognizer to the actual UITableView for left and right swipes.
The action for those swipes were:
[scroll setContentOffset:CGPointMake(currentPointX + 320, PointY) animated:YES];
//Or
[scroll setContentOffset:CGPointMake(currentPointX - 320 , PointY) animated:YES];
This works flawlessly, the only down side is that if the user drags his finger on the UITableVIew that will be considered as a swipe. He won't be able to see half of screen A and half of screen B on the same screen.
You could subclass your scroll view and your table views, and add this gesture recognizer delegate method to each of them...
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:
(UIGestureRecognizer *)otherGestureRecognizer {
return YES;
}
I can't be sure this is exactly what you are after, but it may come close.