I'm unable to get my scrollview to "stick" to the content that is scrolled to. The content is layed out side-by-side (2 UIViews inside UISrollView) and I'm able to slide it over to see, but as soon as I let go it bounces back. My understanding is this is an auto-layout problem however I don't understand what constraints I need to add in order to get this to work. I feel like I've tried everything but it either doesn't work or I get the "ambiguous scrollable content" error.
I finally figured out this problem! There are a lot of posts asking this but none of those answers helped me so I figured I'd update this one in case it helps someone else.
The issue I was experiencing was that the content inside my Scrollview was wider than the actual scrollview (which is the whole point). However when I added the constraint in Xcode to pin the content to the right side of the scrollview, it automatically sets it up with a negative constraint to its parent.
That's not what I intended since the scrollview's content will get resized and I always want my content inside of it pinned to the edge. I simply had to set this constant to 0 and then everything worked!
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I am trying to create a custom subclass of UITableViewCell that displays an image and a few labels to the right of the image. I have my UIImageView and UILabels arranged in stack views, the outermost of which I pinned to all four sides of the content view.
But when I run the app in the simulator, I do not see the image views. Debugging the view hierarchy, I see they are getting clipped.
And digging in a little further by focusing on the outermost stack view with "Show Constraints" on, I don't see my auto layout constraints at all (instead I get an ambiguous position runtime warning for each of the outermost stack views).
The text label that expands to the right is set up with 0 lines and the table view gets a constant estimatedRowHeight value and its rowHeight set to UITableViewAutomaticDimension, so I think if these constraints were working, the rows in the table would size to fit the content. Perhaps notably, any width or height auto layout constraint I add does appear when I debug the view hierarchy, so I know some constraints are present at runtime, I just cannot for the life of me figure out why the constraints relative to the content view are not.
After wrestling with this for a long time and having a much more experienced developer look over my project, it seems as if there was nothing wrong with the way it was set up. Recreating the table view cell from scratch with exactly the same layout and constraints and using the exact same code fixed this issue. I had messed around with the stack views and constraints quite a bit before this started happening, so it might be possible to get Xcode into a place where it does not properly set up constraints when you run the app in the simulator.
Try to solve all warnings which are printed into your console log when you run your application and viewing this screen. Because you can not ignore warnings always, many warnings you must have to remove by correcting or solving issues in your constraint. And that is the only solution which helps you most of the time.
I'm 5 years late to the party, but I managed to find a solution to this problem in my project. If any of the views that are contained in the table view cell have a bad subclass set on them, the intializer defaults them back to a regular UIView and without any of the layout constraints. Hopefully that saves someone the hours it took me!
I'm trying to figure out how to use autolayout, and there seems to be a lack of info about it on the internet. I placed a view within my view controller with three buttons inside it. Before I place any constraints, the buttons show up on the preview. However, as soon as I make ANY constraints, the whole sub view completely stops showing up in the preview. I made a constraint to center vertically, and then one to place it 25 pixels from the left edge. It should know exactly where to place it, but still nothing shows up.
Any ideas on why constraints cause my buttons to not show up?
With Autolayouts the constraints should be as clear as possible. You can try by adding size constraints as well as fix(right, top or bottom) constraints if necessary.
When you don't use auto-layout it positions everything manually. When you enable auto-layout it switches this behaviour off so you have an unconstrained object, which is why it dissappeared.
Turns out I didn't have constraints on the size of the sub view, so it didn't know how to center it. I didn't think I needed that because I thought it would default to what it's already at.
I have a problem here. For last 3-4 days I'm trying to the find the solution but no avail. I'm using a xib to load a view as a subview to scrollView.
I'm using iOS8 and size classes and auto-layout as well.
The problem is that the view gets added to the scrollview but scrollview is unable to go beyond a point. That is I'm not able to scroll till the bottom.
This is frustrating as I have just started to develop iOS apps.
I'm attaching the screenshots for the constraints that I have applied. Hope to get some help here.
The first screenshot is the actual view controller's view that holds the scrollview.And the Place Detail Info View is the placeholder where the view loaded from xib is added. The screenshot also lists the different constraints as well.
The second and third screenshots is of the xib file which i'm trying to load into scrollView.
Please let me know where I have gone wrong.
As said above, the issue is related with the content size of your scroll view. Just try adding width and height (either explicit or implicit: see explanation below) constraints to every direct subview of your scroll view and then define all distance constraints among those.
* By "implicit" width/height constraints I mean things like "aspect ratio", "equal width/height" relation between two views.
P.S. When dealing with scroll view-like controls and auto layout, there should be an exhaustive (some of which may seem redundant) set of constraints for subviews.
Hope this helps.
Your problem is with the view who is immediate subview of your scrollview.In autolayout,scrollView calculate its content size according to its subview.
follow these steps after removing all constarints from this view,i hope u will get your problem solved.
1.for your scroll view,set all 4 constraints i.e leading edge,trailing edge,superview and bottom constraints.
2.now for the view that is immediate subview to your scrollview,set all 4 constraints (leading,trailing,top and bottom),along with these set height constraints and make width equals to scrollview.
if your immediate subview's height is greater than your screen size or scrollview,it will scroll for sure.
run and check whether you are able to scroll and proceed furthur.
after step 2,all your constarints related ambgious type error will resoved.now you can set all other constraints as usual.
for more clear understanding setting constarints in scrollview see this https://www.youtube.com/watch?v=4oCWxHLBQ-A
In interface builder itself there is an option to preview your constraints for all the available devices. This will ensure you that the constraints work fine for all the available devices from Apple. Here is a quick tutorial that will help you with it.
http://adoptioncurve.net/archives/2014/08/working-with-size-classes-in-interface-builder/
Once that is verified and you are still not able to find a suitable solution, then probably there is something wrong in the content size for your scroll view. Try to increasing your scroll view content size.
I hope this should solve your problem.
Happy coding. Cheers :)
I have a pretty complex view and am trying to update it to work with autolayout (while I learn autolayout at the same time). Here is a screenshot of my view:
The only thing that you can't see is that all of these views are wrapped in a containerView and that container is sitting in a vertical scrolling UIScrollView.So if there was a really long description or something you would be able to scroll vertically.
My first problem is that I can't figure out how to get the descriptionView (red background) to adjust it's height dynamically (I have scrolling disabled in IB and again in code). I think it might be related to the bottom constraint to the imageScrollView.
The second problem is that the imageScrollView needs to be removed half the time. It holds multiple pictures of an item. But sometimes the item doesn't have pictures so I just want to remove the scrollView in that instance. I call removeSubview in code and want things to just readjust without having to set up a bunch of new constraints. So I added a top space constraint from the Question/Comments label to the bottom of the description and changed its priority to 900 instead of 1000. This seemed to solve my first problem and when I remove the imageScrollView the description view resized to the size of the content. However my scrollView that holds all of the content didn't scroll anymore, I am assuming that the containerView's height got screwed up or something.
Edit: the more I think about this the more I think that figuring out how to add a contraint for the size the descriptionView's height to match the content will solve the other problem as well. Here is another screenshot with the current constraints.
SOLUTION
I don't feel it is fair to post my own solution as the accepted answer. So I am posting my solution within the question, and giving the accepted answer to Nikita for trolling all the questions related to textViews being sized to their content.
My first problem is solved by using this: Github - Resizable Text View
The second issue was just a matter of setting up the constraints correctly. The red textView had a constraint to the bottom of the superview(contentContainer) (the superview which sets the height of the the main scrollView.) So when I removed textView then the contentContainer view didn't have a height constraint. So I ended up removing the constraint from the textView to the superview (which is the contentContainer) and made a constraint from the bottom of the commentTextView to the contentContainer. This solved the problem. Whenever I remove the red textView everything shrinks up the way I desire.
I'm not sure, that my solution is the best one, but I've done it in the following manner (I think that will help you with red text view): How do I size a UITextView to its content?
Unfortunately, I didn't understand you about second problem. Please, provide more details. Thanks!
Don't remove the image view. Just give it a zero-height constraint. That way you don't have to mess with any of your other constraints.
I am having a very frustrating issue. I know there are all kinds of issues with UIScrollView in iOS7 and XCode 5. I need to implement a scrollview and there are all kinds of tutorials showing you how to do it by switching off auto layout but that then messes with the rest of the views in my app.
I tried the fix of putting my subviews into a container UIView and placing that in the UIScrollView and setting the scrollview's content size to the size of the contained UIVIew. That didn't work. Now I am working with placing everything in the scrollview and it all works with one exception. When I load the view on the simulator or a device the content view is moved down but somewhere around 60 points or so. See image below.
That white space below the title bar on the right is still the scroll view as I can press and drag within it. Adjusting the contentOffset doesn't do any good as that just scrolls the view down slightly. I have no idea what to do here.
Just a little more info: I setup the scrollview and all the subviews in storyboard and the connected them up. Not sure if that has any bearing on it.
Thanks in advance for any help you can provide.
I think your Scrollview top space constraint have 64 pixels. That's a problem. So, set your top space constraint value to 0.
You need to add the constraints before view displayed then contentsize will be set automatically.
Check UIScrollView's autoresizing mask. It has to be set like this.