I have a cell that contains a container with 10 subviews (two of them are simply bounds and the others are labels). The scheme looks like this.
Dynamic labels may contain huge text so the cells should conform the appropriate size to fit the content. The question is how to set up all the constraints manually... I've tried a dozen of times to do it myself but seems I'm not that good at this. The table view supports auto dimension for row height and uses custom estimated height.
In Storyboard it looks this way.
Where blue views are a subviews of View C. A grey view behind is a View B. Bold labels are static and the others are dynamic.
Demo project.
How to setup constraints?
Thank you very much in advance!
I managed to setup your constraints so that you get the result you needed. This is what I get:
I hope this is how you wanted it to look like.
Here is a link with the project.
I will try to explain how I added the constraints so that it makes more sense.
First of all, you have view B which needs to be as big as the contentView. For this you add top/bottom/left/right constraints to the superView. Because you are using automatic dimensions, if you add all constraints with priority 1000(the maximum one), you will get some error with the constraints while running. This is because, before the cell size can be calculated automatically it is zero, so the constraints crash. Therefore, I set the priority for top and trailing space with a priority of 999 so that you don't see the error log anymore. The result is the same.
Then views C needs (top or bottom)/left/right and height constraint
Then you need to add the constraints for the labels. Since you need the right ones to have multiple lines, the constraints need to specify the vertical layout for this particular case. So, you have as follows: first label: top/left to name label and right to super view. All the other have top to the previous one,and bottom to the next one.
for the labels that don't need to resize you just need leading space to parent,horizontal space to the right label and static width. Also, you will need a constraint to align the top with the label on the right.
This is the result I get:
Hope my explanation made sense, just let me know if you have questions. Good luck with your project!
Related
I am working on an iOS 11+ app and would like to create a view like in this picture:
The two labels are positioned to work as columns of different height depending on the label content. The content of both labels is variable due to custom text entered by the user. Thus I cannot be sure which of the the two labels is higher at runtime and there is also no limit to the height.
How can I position the BottomView to have a margin 20px to the higher of the two columns / labels?
Both labels should only use the min. height necessary to show all their text. Thus giving both labels an equal height is no solution.
I tried to use vertical spacing greater than 20px to both labels but this leads (of course) to an Inequality Constraint Ambiguity.
Is it possible to solve this simple task with Autolayout only or do I have to check / set the sizes and margins manually in code?
You can add labels to stackView
One way to do this is to assign equal height constraint to both label. By doing this height of label will always be equal to large label (Label with more content).
You can do this by selecting both labels and adding equal height constraint as mentioned in screen short.
Result would be some think like below
The answer given as https://stackoverflow.com/a/57571805/341994 does work, but it is not very educational. "Use a stack view." Yes, but what is a stack view? It is a view that makes constraints for you. It is not magic. What the stack view does, you can do. An ordinary view surrounding the two labels and sizing itself to the longer of them would do fine. The stack view, as a stack view, is not doing anything special here. You can build the same thing just using constraints yourself.
(Actually, the surrounding view is not really needed either, but it probably makes things a bit more encapsulated, so let's go with that.)
Here's a version of your project running on my machine:
And with the other label made longer:
So how is that done? It's just ordinary constraints. Here's the storyboard:
Both labels have a greater-than-or-equal constraint (which happens to have a constant of 20) from their bottom to the bottom of the superview. All their other constraints are obvious and I won't describe them here.
Okay, but that is not quite enough. There remains an ambiguity, and Xcode will tell you so. Inequalities need to be resolved somehow. We need something on the far side of the inequality to aim at. The solution is one more constraint: the superview itself has a height constraint of 1 with a priority of 749. That is a low enough priority to permit the compression resistance of the labels to operate.
So the labels get their full height, and the superview tries to collapse as short as possible to 1, but it is prevented by the two inequalities: its bottom must be more than 20 points below the bottom of both labels. And so we get the desired result: the bottom of the superview ends up exactly 20 points below the bottom of the longest label.
I am creating a view within IB and and attempting to have 3 UILabels evenly space horizontally across the view. I came across this on SO, https://stackoverflow.com/a/30249550/4597666. I have three UILabels, each have the height and width constrained. Here is what the IB looks like:
I constrained each centered horizontally, and the first UILabel I have the multiplier 3:1, second, 3:3, third 3:5 like the post states.
When I run on my emulator, I don't get the result that I was expecting. It appears all three UILabels are centered horizontally, and the first and third are not offset.
Is there another setting that I'm missing, or another way to properly space the views evenly?
you need to make only one change.
Constraint you set is 3.CenterX to Superview.CenterX all you need to do is interchange the value so that you constraint should look like in below image.
Alternative solution. If you want to set constraints currently you have set then change the ratio from "3:5" to "5:3" and similar for all the labels.
Result:
Hope it helps you solving your problem.
Is there a way to achieve this? I have tried literally everything and nothing has worked for me yet.
So basically what i want to do is the following: I have a scroll view with some labels in it. All the labels get their text from a server and I have set their number of lines to 0 so that they change their height according to the amount of text. However, this does not affect the scrollview content size(even though my labels have constraints set up to the bottom,top,leading and trailing of the scrollview) and the labels go off screen and I am unable to scroll down. Can someone point me in the right direction to how I would set up my constraints, my view hierarchy and etc?
Any help is much appreciated! :)
Late, but this solved it for me:
Set leading (I have a 32pt inset), trailing and top constraints. The trailing will not actually seemingly do anything..
Make the trailing Greater Than or Equal to avoid localization alert.
Finally, add a new Equal Width constraint to the label matching the scrollview. Use the constant to subtract the required padding (I used 64 due to mirror my leading inset).
And voilà! The Label will align correctly both in IB and in-app.
In Scrollview the last view's bottom constraint is so important. You should set its priority to 250 and put it to Greater than or equal.
Remember you should only change the bottom constraint of the last view, which in my case it's the continue button.
I would consider using UITableView instead, it has several benefits:
It allows for reuse of cells, if all the cells look the same
It manages recycling of cells when the number of values you're getting from the server increases (decreases memory pressure when number of cells becomes substantial)
It allows for more flexibility with the content (it's quite often for design to change last second or to evolve over the course of the project)
Most importantly, UITableView support auto sizing cells (as of iOS8), you need to specify the constraints between the label and the borders of the cell
There are several resources to start with:
http://www.raywenderlich.com/73602/dynamic-table-view-cell-height-auto-layout
https://www.captechconsulting.com/blogs/ios-8-tutorial-series-auto-sizing-table-cells
http://www.appcoda.com/self-sizing-cells/
Use a container view in a scrollView
Add constraints to superview (leading, trailing, top, bottom, height,width)
Make IBOutlet of constraints that you are going to update.
Add you all labels inside that view.
Update constrains/frame of your label so that it fits the text.
How much you increase the label height you should increase the container height too.
If the label count is not fixed use custom label class to add subview.
Perhaps you should need to understand how ScrollView works in Storyboard with autolayout.
I have pretty straightforward requirements where two labels must be centered horizontally. So, I have selected them and chose Editor->align->center horizontally. Then added top space to container constraint to both of them. I also need the labels to shrink/grow regarding content size. However, IB shows errors and several warnings. I could make the labels shrink/grow just by adding pin between them (horizontal space) but they will not be centered in that case. Here are the screenshots:
here are the errors and warnings:
UPDATE theraven gave an interesting suggestion to use dummy view for centering it horizontally and pinning two labels to it. I have removed all existing constraints, added this dummy view and center X + center Y constraints to it. Then pined two labels to it (added horizontal space constraints). However, I still get a bunch of errors and warnings:
UPDATE2 Just updating the question, but still no valid answer found. #Theraven workaround works for iPhone4, iPhone4S, iPhone5 and iPhone5S, however it's not real centering but rather a workaround. Therefore for iPhone6 and iPhone6 Plus it doesn't work as leading and trailing spaces will be fixed and won't automatically resize for larger width.
What you could do is add both labels to another view, like a container view. Then you need to center this one horizontally and add the necessary constraints.
To add the containing UIView, you can select both labels, go to Editor -> Embed In -> View.
Then you would need to add constraints to make the containing view fit the two labels. So something like this:
First Label (left one):
Leading Space to Superview
Top and bottom Space to Superview
Horizontal spacing to the next Label
Second Label:
Trailing space to superview
Top and Bottom to superview (or align top with the first one)
Then the containing view should resize as to fit both labels. Then all you need to do is add the top offset constraint for this container view and a horizontal alignment it in the parent view.
This way, the containing view will grow as much as it needs to fit both labels and the space between them and will always be centered in the parent view.
I took a screenshot of my test constraints in case it helps you more.
Hope this was what you were looking for.
To solve this use a blank UIView in between your two labels and center it horizontally. Then pin the two labels either side of the centered blank view. It is common convention to use spacer views like this in auto-layout.
I really don't like the idea of adding another view just for sake of estethic.
Another alternative is to horizontally-center the left view, and horizzontally space the right view of an amout X with the left one.
Then to give the horizontally-align contraint of the first view a negative value equal to the first view width plus half the views distance. Or use multipliers as said in a previous comment.
But this only works with fixed width views i guess.
Use centered UIStackView as a container for two labels with a spacing required.
I didn't really understand what you wish to do.
The error you get (in the first screen shot) is that you are missing constraint for the x position of the labels.
For UILabel you must have constraint both for y and for x position regarding to the container view, when you selected them both and chose Editor->align->center horizontally, you just say that label1.center.x = label2.center.x.
You still need to say where they will be in the container view, you added the top space to container, so you do have the y position, but you didn't say where the x position should be.
You said
I have pretty straightforward requirements where two labels must be centered horizontally
But where they should be in respect to their container?
thanks
Using spacer views is the best possible solution I could figure out, even though it looks ugly for the developer. The user wouldn't even know what's going on behind the scenes and once you have the spacer UIView, you can always reuse it.
I cant for the love of god the the hang of this resizing superview.
I have a UIView *superview with 4 UILabels. 2 function as header for the 2 others.
The content in all 4 are dynamic coming from database.
SizeToFit vs SizeThatFits:(CGSize) vs UIView systemLayoutSizeFittingSize:, passing either UILayoutFittingCompressedSize or UILayoutFittingExpandedSize.
I use autolayout programatically and have set the superview height to be equal or greater to a dummy number.
where and how do I use these SizeToFit vs sizeThatFits:(CGSize) vs UIView systemLayoutSizeFittingSize:, passing either UILayoutFittingCompressedSize or UILayoutFittingExpandedSize. I have read a lot of tips here on stack but ended up with nothing.
DO I need to recalculate the constraints for the superview somewhere specific. Maby setting the height to be ´#property` in its controller class and remove and readd it?
Atm I have tried to put everything everywhere and then some. Still I get the same size end result with the dummy height and text floating outside. Even after setting clipsToBound on subview.
I am scratching my hair of.. help
If you're using Auto Layout, here's what you need to do:
Make sure you aren't adding fixed width and/or height constraints to any of your subviews (depending on which dimension(s) you want to dynamically size). The idea is to let the intrinsic content size of each subview determine the subview's height. UILabels come with 4 automatic implicit constraints which will (with less than Required priority) attempt to keep the label's frame at the exact size required to fit all the text inside.
Make sure that the edges of each label are connected rigidly (with Required priority constraints) to the edges of each other and their superview. You want to make sure that if you imagine one of the labels growing in size, this would force the other labels to make room for it and most importantly force the superview to expand as well.
Only add constraints to the superview to set its position, not size (at least, not for the dimension(s) you want it to size dynamically). Remember that if you set the internal constraints up correctly, its size will be determined by the sizes of all the subviews, since its edges are connected to theirs in some fashion.
That's it. You don't need to call sizeToFit or systemLayoutSizeFittingSize: to get this to work, just load your views and set the text and that should be it. The system layout engine will do the calculations for you to solve your constraints. (If anything, you might need to call setNeedsLayout on the superview...but this shouldn't be required.)
Use container views
In the following example I have a 30x30 image, and the UILabel is smaller than the containing view with the placeholder text. I needed the containing view to be at least as big as the image, but it needed to grow to contain multi-line text.
In visual format the inner container looks like this:
H:|-(15.0)-[image(30.0)]-(15.0)-[label]-(15.0)-|
V:|[image(30.0)]|
V:|[label(>=30.0)]|
Then, set the containing view to match the height of the label. Now the containing view will ride the size of the label.
As #smileyborg pointed out in his answer, connecting the content rigidly to the superview informs the layout engine that the simple container view should cause it to grow.
Yellow alignment rectangles
If you want the yellow alignment rectangles add -UIViewShowAlignmentRects YES in your scheme's list of run arguments.
This almost follows #smileyborg answer and comes with a concrete example.
Won't describe all constraints, but those related to the calculation of the height of UI objects.
[Label] Labels must not have a fixed height constraint, in this case, AutoLayout won't resize labels to fit the text, so setting edge constraints is the key. (green arrows)
[Subview] Steps 1 and 3 are very easy to follow, but this step can be misunderstood. As in the case with labels, subviews must not have height constraint set. All subviews must have top constraint set, ignoring bottom constraint, which can make you think will trigger unsatisfied constraint exception at runtime, but it won't if you set bottom constraint for the last subview. Missing to do so will blow the layout. (red arrows)
[Superview] Set all constraints the way you need, but pay big attention to the
height constraint. Assign it a random value, but make it optional, AutoLayout will set the height exactly to fit the subviews. (blue arrows)
This works perfectly, there is no need to call any additional system-layout update methods.
This was made dramatically easier with the introduction of Stack Views in iOS 9. Use a stack view inside your view to contain all your content that resizes, and then simply call
view.setNeedsUpdateConstraints()
view.updateConstraintsIfNeeded()
view.setNeedsLayout()
view.layoutIfNeeded()
after changing your content. Then you can get your new size by calling
view.systemLayoutSizeFittingSize(UILayoutFittingCompressedSize)
if you ever need to calculate the exact size required for a view.