I'm having some trouble working with UIScrollView in my current project. My intention is to have a variable-size drawable canvas which can extend beyond both sides of the screen, and whose size is determined by the user at runtime. For this purpose, I put in a UIScrollView with a Content View inside of it in my View Controller. Unfortunately, Interface Builder keeps pestering me to define the X and Y axes of my Content View as a constant sizes which isn't possible given my specifications. I've even set the ScrollView.contentSize programmatically in my viewDidLoad method and Interface builder is still giving me errors. All other tutorials I've seen have only talked about one-way scrolling with UIScrollView, so here I am. Here's some screenshots of my storyboard hierarchy as well to make things more clear:
Hierarchy
Errors
Does anyone have any experience/workarounds for this kind of problem?
Interface builder is TRYING to be helpful and make sure that you don't have arbitrary constraints on your content view.
Remember that Interface Builder just cares about the initial state of the views it loads. It does not care what you do with them after they have been loaded.
Make IB happy by giving it some rational initial size for your content view. Then programatically after your scroll view loads you can resize the content view and set the scroll view's content size programmatically.
Related
I have a view and for some unknown reason, it's not receiving any touches. When I debugged the view, I've found out that its views' userInteractionEnabled is set to NO. The problem is that, I haven't set it anywhere; neither in Interface Builder (triple checked) and code. The problem started when I first created the regular UIViewController in Interface Builder, without a subclass or any custom code. I know it's near impossible to tell something without code samples, but my project is heavily complicated, and as I've said, the problem is appearing in a regular UIViewController (no subclass) that I've set in interface builder, so there is no relevant code that would mean anything. The rest of the app just works fine, though.
What can possibly cause all views in a regular, default view controller to become userInteractionEnabled = NO?
Found the answer myself after traversing window's recursive description more carefully. I had a scroll view, and inside that, a content view, and other views inside. I'm on pure auto layout, so my scroll view's content view needs to calculate it's own intrinsic size. I was using a placeholder height for the content view in Interface Builder, to make editing interface visually easier. Apparently, I forgot to connect the last view inside my content view to bottom of my content view with a constraint, resulting in my content view having a height of 0 (though still displaying perfectly as it doesn't have clipping enabled). When it's size was 0, it was calculating userInteractionEnabled as NO automatically without being explicitly set to NO. I've added the required bottom constraint and the problem went away.
I designed about 40 view controllers using a 5.5 inch storyboard layout. After all of that I tested it on the iPhone 4S...big mistake. everything is jumbled together being for a larger screen size. I was able to fix one view controller up using Size Classes. I am wondering if there is any way I can adjust all 40 at the same time, or at least avoid doing this for every single one. It is really frustrating finding this out now. Thanks!
This is a relatively complicated issue you are attempting to solve, but I have two potential solutions. Both suggestions are based on moving your current interface into containing UIScrollView instances
If you are using storyboards, then for each of your view controller scenes, put a UIScrollView as a descendent of the view controller's view. From there, provided your subviews are contained within other views (like a container view for a set of buttons), you can move those into your scroll view. You will have to setup constraints to define the size of the scroll view's content, but this will allow the size of the device to have a smaller impact on the interface as you will get scrolling as needed.
If you are using nib files (.xib) then it is essentially the same thing, but easier. In this case, move a UIScrollView onto the canvas, but not as a subview of the default view. Once that is out there, move the original view to be a subview of the scroll view and set constraints to be 0 from the subview to the scroll view. Finally, right click drag from the File's Owner icon to the scroll view and set that as the view outlet.
Hopefully one of these will help you.
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/
I have a vertically scrolling uiscrollview - imagine an 'about this app' page of a tab bar app which goes on a bit and requires a scrollview. It only contains a few images, a video and some text (only the video has been coded in - the rest have been placed in the GUI). In storyboard (Interface Builder?) Xcode 4.2, everything is set up as it should be and works fine, but the view is only as large as what you see on the screen, is it not possible to manually arrange in storyboard the items that are initially offscreen - that you need to scroll up to? The only way I've found so far is to design them on the visible view then navigate them down with the arrow keys..
In the storyboard select the viewController, then in Attributes inspector change 'size' to 'freeform'. Then change the 'height' of the view/scroll view to as big as you need. The default settings of struts and springs should take care of resizing the view back correctly when the app is run, but you should double check.
I feel your pain. The only way I found is to manually pan the scroll view in the size inspector to reveal the portion of the view that you wish to visually edit.
Use a UIView to contain elements so they are positioned relatively to this view. Add the view as a subview to the scrollview at 0,0.
pan: use the Y coordinate say to -200, then edit the contents.
to place more contents in the hidden part, pan again to reveal new real-estate
when finished, restore the values of the ScrollView's height and X,Y position.
Make sure the scroll view frame rectangle is smaller than the contained view.
New: 3/26/2013
I stumbled upon what I think is even simpler way of dealing with UIScrollView directly in storyboard.
No code needed, just storyboard settings. This maybe new in iOS6.1 / Xcode 4.6
No need to disable constraints (i.e. uncheck "Use autolayout" in File Inspector for storyboard file)
No need to add UIScrollView* scrollView; in .h
No need to add self.scrollView.contentSize = ... in overrides of viewWillAppear or viewDidLoad
Here is what I did (important parts highlighted with **): (see code)
Create a new project with storyboard enabled
Drop in a UIScrollView, set class in identity inspector for view controller
In attributes Inspector, change Size under simulated metrics to Freeform**
Select scroll View; In attributes inspector, turn on "scroll enabled" and "background" to "White" (you'll figure out why - if you don't)
Under Size Inspector (with scroll view selected) change the height to 900 for example**
Add buttons, one on top and one at the bottom
Add a default handler for buttonTouchUpInside for both buttons and simply Log sender.
See Code Select the View Controller and scroll view and check inspectors.
Just change the 'Simulated Size' of the view controller to freeform and set a height that is larger than the usual size, you will be able to see all the outlets you need to edit.
On iOS 6.0 you can drag a Container View inside your Scroll View. This will automatically create a new View for your content, outside of the current scene. You can then resize this view as big as needed to fit your content.
I believe you would still have to set the ScrollView content height at runtime, but at least you can design you content view at once without having to scroll up and down on IB.
Just uncheck the "Autoresize subviews" from any view that you're trying to resize and it should keep all your objects from resizing with it.
I've been struggling with this for a while now, and every single thing I've tried has failed.
Specifically, What I am trying to achieve is a freeform sized modal dialog with a scrollable view containing a container for another view. I have had a lot of varied results, including occasionally having it working correctly. Most often I get it looking exactly correct, but with no scrolling.
In finally downloaded Dickey Singh's code, which worked perfectly but had nothing special. (Excellent clean solution BTW). So, I added a container view to it, exactly as I had in my code, and it broke!
After some experimenting, I worked out what is going on. Just bear with me.
1) Using Auto Layout, the size of the scroll view seems to dictate what the scrolling bounds will be. Setting "contentSize" in "USer Defined Runtime Attributes" seems to have no effect on this, and neither does setting "contentSize" or "bounds" in "viewWillDisplay" or "viewDidLoad". Thus if the initial size of the scroll view is 800x800, that will be all the space that can be displayed. For this reason, when I want a scrollable region, I create a container view and then put the scrolling view inside the content.
2) Without Auto Layout, setting "contentSize" in "User Defined Runtime Attributes" works, as does by setting it programmatically in "viewDidLoad". I prefer to use "User Defined Runtime Attributes" because it keeps the size with the layout. This solution allows you to use scrolling view with more flexibility, since it can be any size at design time.
3) Regardless of Auto Layout, if any view within the scrolling region exactly matches EITHER the horizontal or vertical frame bounds, then the scroll view ceases to function as a scroll view. This applies to my own code and to Dickey Singh's code in every possible configuration that I have tried.
I have no idea what is causing (3), but it is clearly a bug.
I hope this helps everybody out there who is struggling to use scroll view. I imagine that some people are using them without any problem, and some (like me) have had noting but problems with them.
Here's my solution to design a ScrollView with a content larger than the screen entirely in Storyboard (well, except for 1 single line of code :-) :
https://stackoverflow.com/a/19476991/1869369
I'm currently developing an app for iOS 7, and I did exactly as #Dickey Singh's answer, but it doesn't work in the beginning.
After checking the storyboard, I found that we also need to add Auto Layout Constraints for the view controller who holds the scrollView.
It seems that such auto layout constraints would be added automatically before Xcode 5, but now we need to do it ourselves.
The way to add constraints: First select the view controller in the storyboard; Enter 'Editor' in the top menu; Select the 'Resolve Auto Layout Issues'; Select the 'Add Missing Constraints In Container'. Done :-)
I am pretty confused on how to position the controls on a UIScrollView that extends beyond the associated UIView.
I have a long form that needs to be filled out which is on one long UIScrollView. I have read (but can't believe) that there is no way to use InterfaceBuilder in order to position the controls, but instead you have to hardcode X\Y coords. in code (or in IB, but they still won't show as WYSIWIG)
Do you really have to do this all with hard coded coords ?
If so what is the best approach to accomplish this ? What if certain controls can become "hidden"...do you then need to have code that moves the coordinates of all controls further down on the page up ?
Would a better approach be to put all the controls on different views and then add those views to the UIScrollView (at least you could then "see" them in IB...)
I hope I am missing something :-)
You do not have to do all of this in code.
You can just have an XIB file for your embedded UIView. This can be as large as you need it to be. Then have a view controller that loads this XIB, and add its view to your scroll view (setting the content size appropriately.)
As for hiding controls - XIB files probably won't help you there. But you can hide controls and adjust the coordinates of other controls in code. (And change the content size of your scroll view if necessary.) This might be a reason to have different controls in different subviews of your scroll view's content view.
In IB, you can create your UIScrollView at the top of the hierarchy and give it the height that you want. Then you can set your elements as you want, in a WYSIWYG way. Once you finished, you just set the size of your UIScrollView to the size you want and set it under the hierarchy of your ViewController's UIView, and finally in the code, you set the content size of your UIScrollView to the size it takes. Easy !
I would encourage you to read this http://www.uxbooth.com/blog/mobile-form-design-strategies/, it's good advice if you want to design a long form, in a user friendly way :)