I'm trying to have a horizontally scrolling UIScrollView with horizontal paging (kinda like a UIPageController but managed by a single UIViewController)
Because I'm using Auto Layout I have set up everything by using constraints for the views inside, and the scrollview works just fine. However what is odd is that the paging works in a weird way.
Specifically the scrolling becomes really slow and it takes over 5 seconds for the scroll view to snap in place.
I am absolutely puzzled by this because I have done this before with a smaller view (about three "pages" as opposed to 6) and it worked flawlessly.
I have created a sample project to illustrate this; just build it and try scrolling left and right - it works best if you just flick once.
http://mbx.cm/t/MmLIi
The only thing that seems to prevent this is having the viewcontroller manage the scrollview directly (as opposed to have it inside a UIView), but I'm sure the problem lies elsewhere so I figured I'd try my luck to see if any Auto Layout gurus can help me out on this one.
All I did was change your view controller's "Simulated Size" to "Fixed" instead of "Freeform" in the storyboard and it worked fine after that. Not really sure why that would change anything, but it did!
Related
In my app, I am using standard xib files rather than a storyboard and all of the views have the universal size class option selected. When I do the design work, I always work in the any.any frame.
All views are set to use auto layout and size classes.
For just about everything, this works a treat.
The problem comes if I have a UIScrollView in the view. It looks fine in any,any and when I move to compact,any the view looks fine with everything in the right place.
However, if I then test on the device, the scrollview is much larger than the device view, so something has gone amiss.
Adding in scrlView.TranslatesAutoresizingMaskIntoConstraints = true; sorts the problem for the scrollview, but then messes up the rest of the view outside of the scrollview.
The scrollview is set to have scrolling enabled and bounces. Everything else is as it comes when you add the scrollview.
It looks as if the scrollview (on deployment) is set to still be any,any rather than compact,any.
Is there a way to fix this?
I'm trying to create a 3x3 menu, based on a grid of buttons, and I'm facing a lot of problems trying to adapt it to different screen sizes.
Since I want my menu to be equally spaced on the screen (using autolayout tricks on the Storyboard), I have created a custom class with this menu that i'm adding to the center part of the main controller view. The problem is that the menu doesn't fit in small screen (3,5" screens).
Trying to solve this problem, I have created a scrollView in the main screen to add the menu and be able to scroll in small screens.
The problem is that since the view I'm loading in the scrollview, automatically fits to the size of the container (in this case the UIScrollView), only a small part of the menu is appearing in the 3,5" screen, without the option of scrolling (In bigger views it appears equally spaced and everything appears correctly).
How can I solve this UIScrollView problem? Or there is a better solution for this problem?
p.s: I'm sorry, but I don't have enough reputation to add images :(
Uiscrollview with autolayout has some pain into it.
You need to place you're inner views so the scrollview Will be able to understand the contentsize it should use.
You can find more detailed info here
http://infinite-edward.tumblr.com/post/66865604683/uiscrollview-contentsize-and-autolayout-gotcha
I hate iOS scroll views with auto layout, they are driving me crazy!:-D
I have found a method which works perfectly on iOS 7 to use scroll views:
I put the scroll view directly in the main view, attaching the scroll view to the edges of the super view(top,bottom leading and trailing space equals to 0).
Then I put a UIView into the scroll view attached to the edges of the scroll view, (top,bottom leading and trailing space equals to 0).
Then I set the height constraint of the most internal view, I link it at my ViewController class, and I modify its value programmatically.
Or, if the view it's 'static' I put every component using the storyboard into the internal UIView, starting with the one at the Top attached to the top of the super view, the one under, attached with the constraint 'Vertical Spacing' referred to the one over him..and so on... Until the last, which is also attached to the bottom of the UIView..
Everything works fine in iOS 7, it's perfect, but iOS 6 is messing around with the constraint.
When I first launch the view everything is perfect, but it seems to recalculate the constraints even on the didappear(and in a bad way), in fact, if I leave my view while it's scrolled down, when I come back to it(let's say we are in a navigation controller) , is like it's everything 'moved up' and the components at the top are hidden.
Is there a way to make scroll views work in both iOS 6 and iOS 7, I'n thinking at two storyboards as the only solution, please tell me there is another way... :-)
thanks everyone, I post two images explaining my problem, taken from the top of the screen:
Well uncheck use AutoLayout in file inspector and try.
For my current project I wanted to use storyboards and autolayout instead of coding everything by hand. It has gone well so far, but my design has a section of the app where there is a tab bar and one of those tab needs to show four views. The design is to swipe between the four and so I thought to use a scroll view. After some trial and error I found that embedding a Container View in the tab allowed me to easily set up a scroll view and put a couple of view inside it, carefully aligning them using positioning to put them side by side so that each page is one child view. I'm not sure how that plays with the autolayout, and in fact I have the problem that the scroll view won't scroll past the first page position. I can drag about 1/3 of the second page into view, but it never brings that page entirely in view.
I've checked the content size and offset and all of the view positions and it all seems correct. And when I use Spark Inspector to change the scroll offset to the position of the second view/page, the app shows the right page/view and I can even scroll back to the first page. I'm a bit perplexed as to what is causing it to not scroll properly. I don't have any code to show as this is all done in storyboards, but I am wondering if anyone has any ideas as to what is wrong?
Alternately, does anyone have an idea for how to use autolayout and storyboards to set up swiping four adjacent views in a tab? I suspect there are ways to do it. I can think of ways to do it in code, but I'm trying to avoid doing it that way.
EDIT: I set the scroll view delegate to the view controller around it and checked the values of contentSize on scrollViewWillBeginDragging and scrollViewDidScroll. It is always set to {0,0} even after I force set it on viewDidLoad. So I tried setting it every time scrollViewWillBeginDragging is called, which seems work, but I don't understand why this happens and it doesn't smell right. Is there some autolayout constraint that might account for this? Does something cause contentSize get set to {0,0} during the layout process?
For lack of any other answer, I'll use my unsatisfying solution as an answer in the hopes that helps someone else in the future:
I set the scroll view delegate to the view controller around it and checked the values of contentSize on scrollViewWillBeginDragging and scrollViewDidScroll. It is always set to {0,0} even after I force set it on viewDidLoad. So I tried setting it every time scrollViewWillBeginDragging is called, which seems to work.
I'd love to know why the contentSize is being reset if anyone finds out!
Within the pageViewController:viewControllerAfterViewController: method, just before the return statement, the view which is about to be returned as the next page has the correct view frame size.
However immediately after the pageViewController:didFinishAnimating:previousViewControllers:transitionCompleted: method is called, I check the frame size of the newly introduced view controller ([pageViewController2.viewControllers objectAtIndex:0];) and I find it resized.
Note that, I have set [self.pageViewController.view setAutoresizesSubviews:NO] and the autoresizing mask to None for the newly created ViewController.
Any ideas in which step the new ViewController is being resized?
I think the problem is inherently related to the nature of UIPageViewController. It is built from UIScrollView. I don't exactly know why there is strange resizing behavior, but it seems to be particularly pronounced when the view controllers that make up your pages use auto layout. Seemingly, locking the constraints in your page view controllers to the superview makes the elements resize after the transition because the superview is itself getting resized after said transition.
This sucks because Apple is basically pushing all of us to adopt auto layout. Auto layout is awesome, and I recommend everyone use it from now on, but it really really sucks when you use it with a UIPageViewController. They really ought to either scrap that class or build something easier for developers, something that can be dragged into a storyboard outright.
A few things to consider.
1.) Don't lock anything to the "Top Layout Guide" or the "Bottom Layout Guide". Also make sure you have "Constrain To Margins" disabled on any view intended to hug the sides of the screen.
2.) If you are using a label in your individual page / content view controllers, make sure you bind/constrain it to something other than the superview. I wanted to place a label over a UIImageView, so I aligned the label to the leading and top edges of the image view (using AutoLayout constraints only), creating an offset to give the label some margins.
3.) The following would otherwise be a good tutorial. However, it is a bit outdated. I downloaded the project and basically modified it to get a UIPageViewController implementation that works. The only problem with this project is that it doesn't use AutoLayout. I'm currently writing a blog post that more clearly discusses how to use UIPageViewController and Autolayout together.
http://www.appcoda.com/uipageviewcontroller-storyboard-tutorial/