I'm using Auto Layout for an iPhone app to place a button footer bar at the bottom of the screen on both 3.5" and 4" iPhones. The bar is a UIView containing two UIButtons and a UIImageView.
I have a Vertical Space Constraint pinning the bottom space to the superview.
(Editor -> Pin -> Bottom Space to Superview)
It has an Equal relationship. Constant is 60, Standard is NO, Priority is 1000, and Placeholder is NO.
In iOS 7 it works exactly as expected. In iOS 6, it does not. The bar is not a consistent distance from the bottom when I switch between that view controller and its neighbors, and the buttons frequently do not work (they don't even highlight when I tap them). This is all in the simulator, I haven't tried hardware yet. The app is a legacy app, so all of the layout work is in xib files, not storyboards.
Do I need to do something different in iOS 6 to get Auto Layout to work? From what I read, it should be fully compatible with 6 & 7.
Some more information is needed to really get to the heart of the matter. Specifically how auto layout is being used to attach the bar to the bottom.
One thing that gets me over and over though, is remembering to set the translatesAutoResizingMasksIntoConstraints property to false on view(s) that utilize constraints.
Be sure to check the log output while debugging as that will indicate if you have any ambiguous or unsatisfiable constraints. At design time, XCode 4 IB will attempt to add any constraints that you are missing for you. XCode 5 IB will only tell you what you are missing and then at runtime try to add any missing constraints if it can.
Related
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I have set the constraints from the safe area for every labels and textfields but the problem is still occurring. The app perfectly sets only on iphone 11 and iphone 12 simulators only.
(Have shared the screenshot)
I have set the constraints from the safe area for every labels and textfields
No, you don't. If you did, you would not have this problem. You have not correctly set the trailing constraints for these views. In fact, it looks like none of your views has correct constraints.
Every view must be completely configured through constraints as to its position and its size. It must, in other words, be bounded top, left, bottom, and right. Labels and text fields and buttons have an automatic height so you don't need to fix their bottoms, but all of your views need top, left, and right constraints.
I have an issue that makes no sense to me. I have the following setup:
| UITableView |
|| UITableView header ||
||| UIView |||
So inside my UITableView header I have a container view that has leading, trailing and top constraints to its superview. Everything is set up correctly for my test device size (which is iPhone 8). If I change the test device to iPhone 8 Plus I get a strange offset for my trailing constraint - 39pt to the right edge, which is exactly the difference between iPhone 8 plus width in points and iPhone 8.
When I switch between devices in Xcode and see that the trailing constraint is not correct I just make an adjustment myself (change trailing to 1 and then back to 0) and the problem goes away for the particular device.
Initially I thought it is bug in Xcode but when I tested on a device the problem is still there.
I tried setting up a new view controller and adding the same elements but with no effect.
I am attaching screenshots to make my issue clearer.
Before: Adjusting the desired constraints
After: Switching to a device with different size
Adding this as an answer because it's too much for a comment - even though it's really just a confirmation, not a solution.
OK - looked at your project.
I'd say it's an IB / Storyboard bug, which I've seen in other circumstances. If you change the View As... device, the frame does not update immediately.
However, if you change anything that would cause a layout update - such as temporarily changing the background color of a view or font size of a label - everything should snap into place.
You'll also notice that if you select an element and move it slightly, the Update Frames button / menu item becomes enabled... and that will also correctly update the frames.
Note: When I ran the app, regardless of how the layout looked in Storyboard, the constraints correctly sized the views at run-time.
At first I accepted DonMag's answer (thanks for your time) as this really seemed to be an Xcode Interface Builder bug. As I investigated further when having the scenario I mentioned auto layout constraints are not updating the layout when I need it hence not giving me the right view.bounds.
I tried getting it in viewDidLayoutSubviews() without success as well - it was still giving me a size that suits another device.
What did the trick was calling view.layoutIfNeeded() before working with view's bounds. What it does is to update the view's layout immediately. As a result you can access the desired view's bounds.
So I have created my webapplication and when I build it in xcode I have to under "Simulated Metrics" > "Size" set it to 3.5 inch since I have a iPhone 4s.
When I build it and run on the iPhone everything looks perfect, but I want this application to run on iPhone 5/6 aswell, but when I change the size to something else in the Simulated Metrics it gets really messed up on my iPhone. I'm using a webview of my responsive website which shouldn't really care about the screensize but I believe Xcode does. So, is there a solution where xcode automatically detects screensize and makes the webview take the whole viewcontroller? Or do I have to create a application for every screensize?
So, is there a solution where xcode automatically detects screensize
and makes the webview take the whole viewcontroller?
Yes - xcode provides ways to do this. Either through auto layout or using springs and struts. With auto layout you will define a set of rules that your UI will follow. If you want 1 layout for all devices it's fairly straightforward and any tutorial will get you started. with springs and struts you just tell your views how they should grow/stay put depending on screen growing. check this out for a quick introduction to auto layout: http://www.raywenderlich.com/83129/beginning-auto-layout-tutorial-swift-part-1
Or do I have to create a application for every screensize?
Nope.. but you can set different constraints in auto layout for your views to behave very different on different sizes. This gets a little more tricky..
No you do not make a new app for every potential screen size, instead you uses XCode's "auto layout" with a set of "constraints" controlling the size and placement of your widgets. A constraint can be a fixed size for the widget or a given distance relative to another widget (or the parent's border). It is not necessarily a fixed distance, it can also be "my widget needs to be less than 10 pixels apart from this other widget".
The "Simulated Metrics" you refer to in the bottom of the drawing area is only a visual help when laying out you your GUI, it has no effect at runtime. You can safely stick with "Any" width and height.
Read this tutorial to understand XCode's auto layout and constraints:
http://www.raywenderlich.com/50317/beginning-auto-layout-tutorial-in-ios-7-part-1
Quickly, these are the tools used to setup constraints:
In your case, assuming you have only one big view (your webview), you need to set up 4 constraints stating that the webview's left, right, top and bottom sides are 0 pixels away from the parent's left, right, top and bottom borders respectively:
Lay your webview in the middle of your drawing area
Click on it
Click the "pin" button; you will see this view:
Look at the upper part of the dialog: the small square in the middle represents the view you just clicked and the four red lines represent the distances to the parent's side. Set them all to 0 and click "Add 4 constraints". (Note: the lines are initially dashed when not selected; they turn into solid lines when activated.)
Now the frames in the drawing area do not represent what you were expecting: your webview is still in the middle where you placed it initially and does not fill all the available space; XCode is aware that there is a mismatch between the frames and the constraints and shows a warning. You need to update the frames: click the "issues" button and "update all frames".
The image comes from this question on SO:
What is "Constrain to margin" in Storyboard in Xcode 6
Read it to learn about the "Constraints to margin" switch.
I am working on an iOS application and it will be compatible for all devices iPhone 3.5, 4, 4.7, 5.5 inches and iPad also.
I am designing a screen it has 5 subviews, as i view this screen in different screen it does not resize properly.
I am using Auto-layout to manage that screen and I have set the every possible constraint to manage this screen.I have to manage the Subviews height and width as the devices changes.
Following are the steps taken care by me
1)Set the Equal Height Constraint for all subviews
2)Equal Width Constraint for TopView1 and TopView2 set the High priority and set the proper Horizontal spacing, Leading, trailing edges for these two top spaces accordingly.
3)Equal Width Constraint for MiddleView1 , MiddleView2 and MiddleView3 and set the High priority and set the proper Horizontal spacing for these two and vertical spaces from TOpViews accordingly.
4)Set the Width Constraint for bottomView and set the High priority and set the proper Horizontal spacing for these two and vertical spaces from MiddleViews and bottom spaces accordingly.
Prior to this i have not used auto-layout in such complicated way.
Following are the screen shotes depict my problem.
EDIT:
#Ash Furrow please see attached a screen shotes with constraints.
I am laying out the base screen on Any Width Any Height
Please anybody suggest me how should i manage this view
Hmm. Looking at what you've done and the feedback to your question, everything seems correct.
I think I see the problem. The issue doesn't appear to be with your storyboard (here in case anyone is interested), but rather the use of Xcode. Instead of changing the view controller's simulated "Size" metric, use the Assistant Editor to view a preview of whatever device you want. I've tried that, and ran the code, and in both cases they appear to work.
So to recap, use the Preview in the Assistant Editor instead of changing the view controller's properties to resize a view hierarchy.
So I've been using size classes in Xcode 6 beta. I started out by putting some buttons in the middle of the screen in the AnyxAny base class. They showed up on the right side of the screen when I then ran the app in the iPhone simulator. To fix this, I went into the compactxregular size class and dragged the buttons to the middle and spaced them out a little. Then, when I ran it in the simulator, nothing had changed. Why? Is it just a glitch in the beta version or am I not doing something right? It worked when I added a center x alignment constraint to the buttons but I still wanted to do some spacing. (and also, what's the point of the size classes if I could just do it using constraints?)
The size classes are important so you can add individual constraints per size class (using the same storyboard). It has the flexibility to allow you to share certain constraints between all sizes devices and orientations, or just a single.
Click on each constraint you add and on the right menu, you can toggle which size class you'd like to add the constraint for. (It's the + button next to the installed check marks)
You can specify different constraints for different size classes. Watch the WWDDC 2014 video View Controller Advancements in iOS 8 to see how to do it in IB. If you can specify the layout you need without size classes, don’t bother; they’re just for overrides.