UITapGestureRecognizer for UIView in Scroll View doesn't work - ios

I have a uiView with added TapGestureRecognizer. This view is showed in scroll view. If the view is visible on the start, when ViewController with scroll view show, everythink is OK.
Problem occurs when the view is not visible on start (when I need scroll ScrollView to see it) then TapGestureRecognizer doesn't call Tap action.
Did you know how to resolve this problem?

As said by wain
The scroll view also has a gesture recogniser. By default, only 1
gesture recognizer can be handling touches at any one time. You need
to make yourself the delegate of your gesture and then implement
gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:
to return YES. This will allow it to work at the same time as the
scroll view.
For more detail check Apple's Document link
UIGestureRecognizerDelegate_Protocol
and you can also take reference as Example from below link.
Simultaneous gesture recognizers in Iphone SDK
I hope it will be helpful for you.

Related

Scrollview with button(s) that can appear and disappear on tap

I have created a scrollview, to scroll through an array of images, and I have a button and soon to be 6 more on the screen. Now to make the photo nicer, I would simply like to make the buttons disappear and when tapped on again to appear.
Now I know how to do this with just a regular view with simple isHidden, and how to make it reappear when tapped on, but I am largely confused on how to do it on a scrollview because on a regular view, I just put a button over the whole screen but with the scrollview I can't. Any ideas anyone? Still getting better at this one step at a time, and one question at a time.
Here is a screenshot: http://imgur.com/a/Ll6QO
Use a gesture recognizer on the scrollview.
Add a touch gesture recognizer to toggle the visibility of your buttons. Be sure that the gesture recognizer doesn't cancel touches in view, otherwise you won't be able to scroll.

UIScrollView scrolling using a gesture on the overlaid view

Consider the view hierarchy in the figure below:
OverlayView is simply a control view that has some custom controls on it. It also has multiple tap/swipe gesture recognizers. The ScrollView is the scroll view that needs to be scrolled based on the interactions with OverlayView. The OverlayView has the same frame as that of the ScrollView.
I need a way to add some kind of swipe/pan gesture setup configured for the OverlayView such that I can scroll the underlying ScrollView as if I am interacting with it.
There seems to be two different approaches:
Recognize the gesture on the OverlayView and pass it to ScrollView. But I am unsure what gestures to use and how to make ScrollView interact with them.
Ignore all the touches on the OverlayView unless they are on the controls. Pass these touches to the underlying ScrollView. This seems like the easier approach; but I am not sure how to proceed with this either.
Does anybody have any kind of sample code for some project or a similar exercise they worked on before? If not, any pointers whatsoever?
Option 2 is what I was going to recommend. There is a method you can override called hitTest:withEvent: on UIView.
You return a view from it. So if the touch needs to go through to the scroll view then return the scroll view. Else return self.

UIScrollView - scroll or swipe?

In my app I have a UIScrollView and I need to swipe left and right from one picture to the next, but I also need to recognize a scroll.
How do I differentiate between a scroll and a swipe with UIScrollView?
I believe you're actually looking for is an implementation of UIScrollView with Paging, as you do not need to handle the touch events yourself, or determine if they are scrolls or swipes.
The Apple Documentation on Scroll Views and Paging Mode should help you get started
Look into the UIScrollView Delegate Methods. ScrollView can detect different types of actions drag etc or add swipeGesture directly to the scroll view
StackOverflow has questions already on this
iOS: UIScrollView detecting Swipe Gesture
Setting up UIScrollView to swipe between 3 view controllers
How to recognize swipe gesture in UIScrollView

UITableViewCell Editing is very difficult to show

I want my table view cell to show the Delete bar on the right side when the user swipes. However, the table view is in a UIScrollView, and although it is at the far right side, and swiping left does not move the scroll view, the table view cell makes it difficult to edit.
In order to trigger the swipe for editing, I must swipe very fast and in a perfectly horizontal line. The speed required is far more than you can expect users to even want to do, and would not be expected at all from a user's perspective.
I believe the scroll view is the cause, but I cannot be certain. No gesture recognizer is present.
How can I prevent the scroll view from mucking up this experience?
Putting a tableView or webView in a scrollView is not advised, because of the exact problem you are having. Your best bet is to find a way around putting it in a scrollView. Other than modifying your tableView to not be in the scrollView, you might try moving your tableView to the front. [superView bringSubviewToFront:tableView]; hope this helps.
You could try using the gesture recognizer delegate methods for this. I don't have Xcode in front of me, but if you use gestureRecognizer:shouldRequireFailureOfGestureRecognizer: and just fail the scrollView's swiping gesture if the gesture recognized is that of the swiping of the table view cell. Check UIGestureRecognizerDelegate in the docs.

ios move touch event between two uiscrollview

I'm building an iOS layout which consists of a UITableView and a UIScrollView. The UIScrollView is inside a table cell of the UITableView and can be scrolled both horizontally and vertically. The diagram below shows this situation. If the user begins scrolling down/up on the UIScrollView the scrolling event should trigger setContentOffset of the table view, and not setContentOffset for the scroll view while the top of the scroll view will be on the dotted line (it's constant height). Then a scrolling touch event should trigger setContentOffset for the scroll view, not for the table view.
In another case: When the user starts scrolling on the table view, it should trigger setContentOffset for the table view, until the scroll view reaches the dotted line. Then the scroll view should handle setContentOffset.
My problem is how to transfer touch events between the table view and the scroll view during one sliding action.
This sounds like one of those cases where you want something quite specific and custom. So trying to do something clever with the gesture recognizers won't be enough.
The main problem is that the ways you can control gesture recognizers such as with gestureRecognizer:shouldReceiveTouch: and gestureRecognizerShouldBegin: only affect the start of the gesture (or for new touches, not ongoing ones), but you want a single ongoing gesture to transition between controlling each view. So for this reason I think you will need to place a large transparent view over your entire screen with a pan gesture recognizer on it and in your handlePan method decide which view you want to adjust and then call setContentOffset directly on that view. You can use the translation of the pan recognizer and the existing content offset to calculate the new one. I know this isn't very elegant, but I can't think of another way to achieve the effect you want.
I'm not sure if this is going to work, but you could try doing something like this:
Option
self.scrollView.panGestureRecognizer = self.tableView.panGestureRecognizer;
Option
[self.scrollView addGestureRecognizer:self.tableView.panGestureRecognizer];
Option
[self.tableView.panGestureRecognizer requireGestureRecognizerToFail:self.scrollView.panGestureRecognizer];

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