I am using a UITableView in my application to show a set of images under each section in a UITableView.I have a requirement which makes the UITableView to scroll to next section if the swipe is done with two fingers.
Can some one help me in making the UITableView respond to two finger swipe.I tried by assigning a swipe gesture with number of touches assigned to two but the table responds to normal traditional scroll.
Can someone suggest a way to implement this.If possible with pieces of code which is well appreciated.
TNQ
[swipeGesture setCancelsTouchesInView:TRUE];
This will make the gesture recognizer swallow the touches.
Hope this helps.
Cheers!
Related
guys, I'm totally new to Objective C and XCode, so don't be too harsh on me for such a question. In fact, this is my first question on StackOverflow ever. The problem is the following:
I need functionality for closing the keyboard when tapping or scrolling anywhere outside the textField that is currently first responder.
I managed to implement it for tap and horizontal swipes with the following code (right swipe example):
UISwipeGestureRecognizer *swipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(closeKeyboard:)];
swipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionRight;
[self.tableView addGestureRecognizer:swipeGestureRecognizer];
swipeGestureRecognizer.cancelsTouchesInView = NO;
And in fact, later I figured out how to do it using solely interface builder. But vertical swipes just would not work, neither when I do them programmatically, nor through the IB. I suspect that the problem is that my tableView scrolls vertically on the screen, thereby preventing the call of the swipe, but I still have no idea on how to overcome this issue.
I would greatly appreciate your help! Thanks.
I saw, that you are trying to add this vertical gesture to a tableView. So you don't need to add a vertical swipe gesture . You have to implement UIScrollViewDelegate protocol, and implement the -scrollViewDidScroll: or -scrollViewWillBeginDragging: methods. In these methods you can catch if your tableview scrolling, and if your tableView is scrolling, call your closeKeyboard method
the UITableView basically uses UIScrollView & when you implement the UITableView delegate, you also implement the UIScrollView delegate (because behind the scenes, the UITableViewDelegate has implemented the UIScrollViewDelegate)
You do not have to manually implement the UIScrollViewDelegate & you can simply start using any UIScrollView delegates you want such as the -(void)scrollViewDidScroll:
But if you want vertical swipes to work on the tableview then it can be done in the following dirty & totally buggy technique. (Basically this is how NOT to do it)
MAIN property is setDelaysContentTouches on your tableView object to NO.
setDirection on your UISwipeGestureRecognizer object to detect vertical up & vertical down swipes.
Set the swipe gesture onto the tableView object.
example:
[self.tableView setDelaysContentTouches:NO];
UISwipeGestureRecognizer *mySwipe = [[UISwipeGestureRecognizer alloc]
initWithTarget:self
action:#selector(closeKeyboard:)];
[mySwipe setDirection: UISwipeGestureRecognizerDirectionUp | UISwipeGestureRecognizerDirectionDown];
[self.tableView addGestureRecognizer:mySwipe];
Finally, you'll get it to work but it works real bad.
Most of the times, the swipe is ignored since you need to swipe
really really fast and cover a decent distance within the swipe action.
When the swipe works, the table does not scroll.
So, as you see, it's really sad and dirty thing to do.
The reason is that the scrollView handles the content touches in a very specific way.
To decide if the touch is to be handled or to be forwarded, the
UIScrollView starts a timer when you first touch it:
If you haven't moved your finger significantly within 150ms, it passes the event on to the inner view.
If you have moved your finger significantly within 150ms, it starts scrolling (and never passes the event to the inner view). Note:
how when you touch a table (which is a subclass of scroll view) and
start scrolling immediately, the row that you touched is never
highlighted.
If you have not moved your finger significantly within 150ms and UIScrollView started passing the events to the inner view, but then
you have moved the finger far enough for the scrolling to begin,
UIScrollView calls touchesCancelled on the inner view and starts
scrolling. Note: how when you touch a table, hold your finger a
bit and then start scrolling, the row that you touched is highlighted
first, but de-highlighted afterwards.
These sequence of events can be altered by configuration of
UIScrollView:
If delaysContentTouches is NO, then no timer is used — the events immediately go to the inner control (but then are canceled if you move
your finger far enough)
If cancelsTouches is NO, then once the events are sent to a control, scrolling will never happen.
Note that it is UIScrollView that receives all touchesBegin,
touchesMoved, touchesEnded and touchesCanceled events from CocoaTouch
(because its hitTest tells it to do so). It then forwards them to the
inner view if it wants to, as long as it wants to.
source: https://stackoverflow.com/a/844627/2857130
I need a "PickerView", that behaves like a normal UIPickerView, but only shows one row of data and has a custom design.
Something like you see in the image, showing the transition from subview 1 to subview 2. After the user lifts his finger and after the scrolling stops, only one subview will be shown:
IMAGE
So basically a scrollview which:
is endless in both, positive and negative directions by showing the same entries over and over
uses paging across several subviews
only shows one subview when not scrolling, and no more than two subviews when scrolling.
I can get a endless scrollview to work, but not with paging enabled. Paging will always limit my scrolling to the next subview.
So I'm thinking about creating my own UIView subclass which custom scrolling behaviour to mimic a UIPickerView. But before doing so, I wanted to get some opinions about the idea in general. Is creating a custom UIView the right way to go? Anyone has some experience with the expected performace? (There will be timers to handle the scrolling algorithm, which has to be recreated of course... :)
Another approach would be to subclass UIScrolView and implement the paging myself. I know when the scrollView starts decelerating
, so maybe there is a way to overwrite the contentOffset to have it scroll into the right position...?!
Any help is appreciated! Thanks!
Here is a great custom component, which seems to be able to do everything you need:
http://dev.doukasd.com/2011/04/infinite-scrolling-dial-control-for-ios/
It's not endless, but rather a modified UITableView with a huge number of cells.
Would it be feasible to just use a UIPickerView, but clipped to the middle row? You could turn off showsSelectionIndicator to remove the overlay and have the delegate pass back custom row views.
I want something similar to how the iPhone homescreen works. I have my scrollview inside my main view, which scrolls to the right, but when you touch on the UIButtons, they become highlighted and dragging means they don't end up getting pressed but also the scrollview doesn't end up scrolling. It doesn't do this on the homescreen. How can i make it similar to this?
A touch-down-drag is a completely different event. Apple doesn't support this directly—you'd have to code it in—start tracking the touches using the gesture responders as soon as a touch-down-inside is detected, then scroll the same amount, and stop scrolling at a touch-up-outside (or inside). This would most likely fall under the category of unusual use of interface elements, and could very well get you rejected.
I think this is a better answer to the question:
UIScrollview with UIButtons - how to recreate springboard?
Hej folks,
I got an UIView in my application and want to implement kind of a swipe gesture. I know how I detect this gesture (touchesBegan: and touchesEnded: for example is x coordinates are distanced more than 100 pixels or something else) but I really don´t now how to animate my needs. In fact my UIView will contain subviews which are 9 UIButtons. On swipe I want to change the set of buttons programatically...any solutions out there? Primarily need the animation!
EDIT: I thought about programatically moving the buttons off-screen to the left and at the same time move the new ones on-screen from the right side. But it seems I don't really know how to realize this...isn't it too much leaking at the same time? Please give me a hint!
It's seem that you want to recreate somethings like the springboard but with button instead of icon.
I can suggest you to use UIScrollView.
why you don't load just a new view with the other button set in your window after the swipe gesture was detected?
Questions similar to this have been asked all over, but I haven't been able to find a solution to my specific problem, so here goes.
I have a UIViewController with a UIScrollView in its view. Within the scrollview, I have a number of regular uiview subviews. I want to be able to detect whether the scrollview swipe was with one or two fingers, and to cancel the scroll and call some other method in one of those cases. Can anyone help me with this?
If you are on OS 3.2 + try giving UIGestureRecognizer a try. You can detect swipes of any number of fingers very easily.
http://developer.apple.com/iphone/library/documentation/uikit/reference/UIGestureRecognizer_Class/Reference/Reference.html