I have a simple custom UITableViewCell which has profile image on the left, title and detailsLabel on the right. I have used Auto Layout constraints to set all the views on the screen. But the detailsLable text is short and profile image cuts off.
Let me know how to fix it. I could make the image small which is shorter than the height of title and label combined, but I want the big image.
// adding subviews
contentView.addSubview(profileImageView)
contentView.addSubview(nameLabel)
contentView.addSubview(jobTitleDetailedLabel)
// constraint for the views
profileImageView.topAnchor.constraint(equalTo:self.contentView.topAnchor, constant:10).isActive = true
profileImageView.leadingAnchor.constraint(equalTo:self.contentView.leadin gAnchor, constant:10).isActive = true
profileImageView.widthAnchor.constraint(equalToConstant:50).isActive = true
profileImageView.heightAnchor.constraint(equalToConstant:50).isActive = true
nameLabel.topAnchor.constraint(equalTo:self.contentView.topAnchor, constant:10).isActive = true
nameLabel.leadingAnchor.constraint(equalTo:self.profileImageView.trailingAnchor, constant:10).isActive = true
nameLabel.trailingAnchor.constraint(equalTo:self.contentView.trailingAnchor).isActive = true
jobTitleDetailedLabel.topAnchor.constraint(equalTo:self.nameLabel.bottomAnchor).isActive = true
jobTitleDetailedLabel.leadingAnchor.constraint(equalTo:self.profileImageView.trailingAnchor, constant:10).isActive = true
jobTitleDetailedLabel.trailingAnchor.constraint(equalTo:self.contentView.trailingAnchor).isActive = true
jobTitleDetailedLabel.bottomAnchor.constraint(equalTo:self.contentView.bottomAnchor, constant:-10).isActive = true
Just add jobTitleDetailedLabel height constrain to be greaterThanOrEqualToConstant profileImageView height + 10 for Margin
because if jobTitleDetailedLabel hight is less than Image hight it will make it small cell row
self.jobTitleDetailedLabel.heightAnchor.constraint(greaterThanOrEqualToConstant: 60).isActive = true
Make sure to constrain the cell's contentView's bottom anchor to be greaterThanOrEqualTo both the profileImageView's bottom anchor and the jobTitleDetailedLabel's bottom anchor. The cell will expand according to whichever is larger.
So you need to remove the jobTitleDetailedLabel's bottom anchor constraint and add:
contentView.bottomAnchor.constraint(greaterThanOrEqualTo: profileImageView.bottomAnchor, constant: 10).isActive = true
contentView.bottomAnchor.constraint(greaterThanOrEqualTo: jobTitleDetailedLabel.bottomAnchor, constant: 10).isActive = true
Also set the contentHuggingPriority of the nameLabel to high in order to ensure that the nameLabel keeps its intrinsic height (the height the text takes up).
nameLabel.setContentHuggingPriority(UILayoutPriority.defaultHigh, for: .vertical)
Finally set the cell's row height to UITableviewAutomaticDimension in the storyboard or through code - tableView.rowHeight = UITableViewAutomaticDimension
Related
I have two labels set completely programmatically. Label two should always be up against the right edge of label one (with a small space between them). Label one has its width set to be equal to its content size unless it hits a max width. Visually:
|Label one| |Label two|
I need the following constraints:
Label one should resize width wise unless it hits a max size.
Label two should always be up against the right edge of label one
How do I set these constraints programmatically?
lessThanOrEqualToConstant for the widthAnchor should do the job.
let labelOne = UILabel()
labelOne.text = "label1"
let labelTwo = UILabel()
labelTwo.text = "label2"
labelOne.translatesAutoresizingMaskIntoConstraints = false
labelTwo.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(labelOne)
view.addSubview(labelTwo)
NSLayoutConstraint.activate([
labelOne.topAnchor.constraint(equalTo: view.topAnchor),
labelOne.leadingAnchor.constraint(equalTo: view.leadingAnchor),
labelOne.widthAnchor.constraint(lessThanOrEqualToConstant: 100),
labelTwo.leadingAnchor.constraint(equalToSystemSpacingAfter: labelOne.trailingAnchor, multiplier: 1),
labelTwo.topAnchor.constraint(equalTo: view.topAnchor)
])
I agree with #Kevvv answer but you have to also assign trailing constraint of labelTwo to view's trailing, because if labelTwo width will increase if content size is more.
just add one or more constraint
labeltwo.trailingAnchor.constraint(greaterThanOrEqualTo: view.trailingAnchor)
I tried my own "placeholder in a UITextView" implementation.
My approach was this:
I create a UILabel in a UITextView subclass, and I set the constraints of the UILabel to match the size of its superview (UITextView).
This is the code where I create the UILabel and assign it to a class variable named placeholderLabel in awakeFromNib():
placeholderLabel = UILabel()
placeholderLabel.text = placeholder
placeholderLabel.numberOfLines = 0
placeholderLabel.lineBreakMode = .byWordWrapping
placeholderLabel.textAlignment = .left
The following code is where I add the UILabel as a subview, and I set the constraints, again in awakeFromNib():
placeholderLabel.translatesAutoresizingMaskIntoConstraints = false
placeholderLabel.leftAnchor.constraint(equalTo: leftAnchor, constant: textContainerInset.left + 4).isActive = true
placeholderLabel.topAnchor.constraint(equalTo: topAnchor, constant: textContainerInset.top).isActive = true
placeholderLabel.rightAnchor.constraint(equalTo: rightAnchor, constant: textContainerInset.right + 4).isActive = true
placeholderLabel.bottomAnchor.constraint(lessThanOrEqualTo: bottomAnchor, constant: textContainerInset.bottom).isActive = true
I also have a property where I set the placeholder's text, where I have a didSet observer, which sets placeholderLabel's text and then calls layoutIfNeeded() in order to have the constraints recalculated in case the UILabel extends to a second (or third, etc) row:
var placeholder: String = "" {
didSet {
placeholderLabel.text = placeholder
layoutIfNeeded()
}
}
The issue is that I have the following result:
The UILabel extends beyond it's superviews bounds (to the right), and it appears that it doesn't respect the constraints. I run the visual debugger which confirmed the same thing:
It seems that there is a width constraint which follows the UILabel's content width instead of following the constraint I have set in place (in this case it creates a width of 431 whereas the superview's width is 288).
Is there something that I miss?
First of all you have to use a negative value for the right constraint's constant (or - to use a positive value - switch the items placeholderLabel.rightAnchor / rightAnchor).
The real problem though is the fact that UITextView is a subclass of UIScrollView. In your case adding the UILabel with a large text as a subview and constraining its edges to the textview's edges results in the textview's contentSize to grow. The textview becomes horizontally scrollable.
Printing out the textview's contentSize before and after adding the label results in different values for the width (before: 335.0, after: 505.0).
Proof: https://www.dropbox.com/s/eogvl2c5r76c6cl/example.mov?dl=0
You could work around that problem by not creating the right but a width constraint instead:
// placeholderLabel.rightAnchor.constraint(equalTo: rightAnchor, constant: -(textContainerInset.right + 4)).isActive = true
placeholderLabel.widthAnchor.constraint(equalTo: widthAnchor, constant: -(textContainerInset.left + 4 + textContainerInset.right + 4)).isActive = true
with right should be minus
placeholderLabel.rightAnchor.constraint(equalTo: rightAnchor, constant: - textContainerInset.right - 4).isActive = true
I'm using the following code to constrain a view to the left and right anchors of a parent UIScrollView.
Despite the right anchor and the left anchor being set to the ScrollView's left and right anchors, the view does not expand to fill the scrollview.
Note: The gray background in this image is the UIScrollView's background, so I know that's properly constrained to its parent view.
Code:
self.wtfView.translatesAutoresizingMaskIntoConstraints = false
self.wtfView.backgroundColor = UIColor.orange
self.wtfView.topAnchor.constraint(equalTo: self.passwordField.bottomAnchor, constant: 40.0).isActive = true
self.wtfView.leftAnchor.constraint(equalTo: self.containerView.leftAnchor, constant: 40.0).isActive = true
self.wtfView.rightAnchor.constraint(equalTo: self.containerView.rightAnchor, constant: 40.0).isActive = true
self.wtfView.heightAnchor.constraint(equalToConstant: 50.0).isActive = true
self.wtfView.bottomAnchor.constraint(equalTo: self.containerView.bottomAnchor, constant: 40.0).isActive = true
https://imgur.com/a/U88iW
Edit:
The following code works correctly, but I would prefer to use the left+right anchor technique to specify the width, and not at a width constraint. Shouldn't that be possible?
self.wtfView.translatesAutoresizingMaskIntoConstraints = false
self.wtfView.backgroundColor = UIColor.orange
self.wtfView.topAnchor.constraint(equalTo: self.passwordField.bottomAnchor, constant: 40.0).isActive = true
self.wtfView.leftAnchor.constraint(equalTo: self.containerView.leftAnchor, constant: 40.0).isActive = true
self.wtfView.widthAnchor.constraint(equalTo: self.containerView.widthAnchor, constant: -80.0).isActive = true //THE DIFFERENT ONE
self.wtfView.heightAnchor.constraint(equalToConstant: 50.0).isActive = true
self.wtfView.bottomAnchor.constraint(equalTo: self.containerView.bottomAnchor, constant: 040.0).isActive = true
The reason for this is that the contentView of the UIScrollView still doesn't know that you want it to take up the width of it's parentView.
You can fix this by adding the following constraint in iOS11:
self.containerView.contentLayoutGuide.widthAnchor.constraint(equalTo: self.view.widthAnchor).isActive = true
This says "Hey, I want you to lock the content Width to the width of the superview.
Pre iOS 11 you can simply constrain a subview to both the parent view's left and right anchors AND the content view's left and right anchors.
Like so:
self.wtfView.leftAnchor.constraint(equalTo: self.view.leftAnchor, constant: 40.0).isActive = true
self.wtfView.rightAnchor.constraint(equalTo: self.view.rightAnchor, constant: 40.0).isActive = true
Much like, Aleksei's recommendation you are now constraining the width to a rigid value ( the width of the parent view ), and the scrollview will use that to decide the width of the scrollview.
may be try to provide:
self.wtfView.widthAnchor.constraint(equalTo: self.containerView.widthAnchor, constant: -40.0).isActive = true
I have a UIView in my swift code
let profile_inf_wrapper: UIView = {
let v = UIView()
v.backgroundColor = .red
v.translatesAutoresizingMaskIntoConstraints = false
return v
}()
profile_inf_wrapper.topAnchor.constraint(equalTo: view.topAnchor, constant:64).isActive = true
profile_inf_wrapper.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
profile_inf_wrapper.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
profile_inf_wrapper.heightAnchor.constraint(equalToConstant: view.frame.height/4).isActive = true
backgroundImageView.topAnchor.constraint(equalTo: profile_inf_wrapper.topAnchor).isActive = true
backgroundImageView.leftAnchor.constraint(equalTo: profile_inf_wrapper.leftAnchor).isActive = true
backgroundImageView.rightAnchor.constraint(equalTo: profile_inf_wrapper.rightAnchor).isActive = true
backgroundImageView.bottomAnchor.constraint(equalTo: profile_inf_wrapper.bottomAnchor).isActive = true
profileImage.centerYAnchor.constraint(equalTo: profile_inf_wrapper.centerYAnchor).isActive = true
profileImage.leftAnchor.constraint(equalTo: view.leftAnchor, constant:25).isActive = true
profileImage.widthAnchor.constraint(equalToConstant: 110).isActive = true
profileImage.heightAnchor.constraint(equalToConstant: 110).isActive = true
usernameLabel.topAnchor.constraint(equalTo: profile_inf_wrapper.topAnchor, constant:40).isActive = true
usernameLabel.leftAnchor.constraint(equalTo: profileImage.rightAnchor, constant:20).isActive = true
countryIcon.topAnchor.constraint(equalTo: usernameLabel.bottomAnchor, constant:10).isActive = true
countryIcon.leftAnchor.constraint(equalTo: profileImage.rightAnchor, constant:20).isActive = true
countryIcon.widthAnchor.constraint(equalToConstant: 25).isActive = true
countryIcon.heightAnchor.constraint(equalToConstant: 25 ).isActive = true
countryName.topAnchor.constraint(equalTo: usernameLabel.bottomAnchor, constant:5).isActive = true
countryName.leftAnchor.constraint(equalTo: countryIcon.rightAnchor, constant:10).isActive = true
countryName.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
All these elements are the subviews of profile_inf_wrapper.Sometimes view.frame.height/4 is too small and i want to be able to resize the UIView based on it's content
There's a property in UIView called intrinsicContentSize. It returns the smallest size that the view would need show all of it's content.
While the default implementation is not very useful because a UIView doesn't have any content on it's own, all of the default subclasses implement it.
A UILabel will return a size that fits the text perfectly, and a UIButton will return a size that fits it's contents plus whatever spacing you've added. You get the gist of it.
You can take advantage of this property by only constraining either width or height of a view, not both. If you constrain the width of a UILabel and add more text, it will grow vertically.
Finally, when you add subviews to a UIView, and you add constraints to both margins of an axis (top and bottom or left and right), as long as there's a "chain" of constraints and views, and the view doesn't have any constraints on the size, it will expand to fit.
For example, if you have a view with a label and a button, vertically arranged, if the label is constrained to the top, then constrained to the button, and the button is constrained to the bottom, as long as the container view doesn't have a height constraint, it will expand to fit the two views plus the margins perfectly.
Your goal should always be to use the least amount of constraints to express your design, without removing useful constraints. Make sure you take advantage of the intrinsicContentSize.
For setting the height of uiview dynamically you have to add height/bottom constraint to the view in your problem it might be
profile_inf_wrapper.heightAnchor.constraint(equalToConstant: view.frame.height/4+countryName.frame.size.height).isActive = true
you also need the view size to fit to get actual updated size
like
countryName.sizeToFit()
And then update layout if needed to get all affect
The first thing you want to do is make a reference to the height constraint of profile_inf_wrapper.
var profile_inf_wrapper_height_constraint: NSLayoutConstraint?
I don't know the details of your content, but when the view needs resized, you can check that with a conditional in your viewController,
if contentRequiresResizing {
profile_inf_wrapper_height_constraint.constant = view.frame.width/3
else {
profile_inf_wrapper_height_constraint.constant = view.frame.width/4
}
By referencing constraints, it allows you to support dynamic UI changes easily.
As a side note, I would recommend renaming your UIView variable name so that the reference constraint isn't so long. The Swift 3 API guidelines also support lowerCamelCase, as opposed to underscore naming.
so as you will see below I have a scrollview and I want to add it the the UIViewControllers root view. When I have it constrained to the top, right, bottom, and left I expect to see the red color take up the whole screen. This obviously works, but I want to add a subview to the scrollview that will wrap all the child views. How would I go about doing that?
I have added the view and I have set the same constraints except this time they are set from the wrapper view to the bounds of the UIScrollView, and the blue background color doesn't show anywhere. Also feel free to point out if this is a bad idea, but I thought I could just have it be constrained to the bottom and it will automatically extend the scrollviews content size as needed. This seems to work when I had all the subviews in the scrollview without a wrapper and the last view would extend the content size.
scrollView = UIScrollView(frame: view.bounds)
scrollView?.showsVerticalScrollIndicator = true
scrollView?.backgroundColor = .red
scrollView?.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(scrollView!)
scrollView?.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
scrollView?.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
scrollView?.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
scrollView?.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
//setup wrapper view
let subviewWrapper = UIView()
subviewWrapper.translatesAutoresizingMaskIntoConstraints = false
scrollView?.addSubview(subviewWrapper)
subviewWrapper.backgroundColor = .blue
subviewWrapper.topAnchor.constraint(equalTo: (scrollView?.topAnchor)!).isActive = true
subviewWrapper.leftAnchor.constraint(equalTo: (scrollView?.leftAnchor)!).isActive = true
subviewWrapper.rightAnchor.constraint(equalTo: (scrollView?.rightAnchor)!).isActive = true
subviewWrapper.bottomAnchor.constraint(equalTo: (scrollView?.bottomAnchor)!).isActive = true
Actually this is a very good idea. I always set up my scrollViews this way. I usually call the view contentView, but it is the same idea.
You're almost there. You haven't yet given Auto Layout anything to go on to figure out the size of your subviewWrapper. The constraints you've set so far pin the subviewWrapper to the edges of the scrollView's content area, but this just establishes the fact that as the subviewWrapper grows, the content size of the scrollView will expand. Currently your subviewWrapper has 0 width and 0 height which is why you see no blue.
Below are 3 examples of how you might establish the size of your subviewWrapper.
Note: Each of the following examples is completely independent. Look at each one separately and as you try them, remember to delete the constraints added by the previous example.
Example 1: Make subviewWrapper 1000 x 1000:
Set constraints to make your subviewWrapper 1000 x 1000 and you will see the blue and it will scroll in both directions.
subviewWrapper.widthAnchor.constraint(equalToConstant: 1000).isActive = true
subviewWrapper.heightAnchor.constraint(equalToConstant: 1000).isActive = true
Example 2: Vertical only scrolling with content size 2X of scrollView height:
If you set the width of your subviewWrapper to be equal to the width of the scrollView then it will only scroll vertically. If you set the height of subviewWrapper to 2X the height of scrollView, then your blue area will be twice the height of the scrollView.
subviewWrapper.widthAnchor.constraint(equalTo: scrollView!.widthAnchor, multiplier: 1.0).isActive = true
subviewWrapper.heightAnchor.constraint(equalTo: scrollView!.heightAnchor, multiplier: 2.0).isActive = true
Example 3: Size of subviewWrapper set by its subviews:
You can also establish the size of your subviewWrapper by adding subviews to it that are fully specified in size and connected in a chain from the top of subviewWrapper to the bottom, and from side to side. If you do this, Auto Layout will have enough information to compute the size of your subviewWrapper
In this example, I've added a yellow 600 x 600 square to the subviewWrapper and set it 100 points from each edge. Without having explicitly set a size for subviewWrapper, Auto Layout can figure out that it is 800 x 800.
let yellowSquare = UIView()
yellowSquare.translatesAutoresizingMaskIntoConstraints = false
yellowSquare.backgroundColor = .yellow
subviewWrapper.addSubview(yellowSquare)
yellowSquare.widthAnchor.constraint(equalToConstant: 600).isActive = true
yellowSquare.heightAnchor.constraint(equalToConstant: 600).isActive = true
yellowSquare.topAnchor.constraint(equalTo: subviewWrapper.topAnchor, constant: 100).isActive = true
yellowSquare.leadingAnchor.constraint(equalTo: subviewWrapper.leadingAnchor, constant: 100).isActive = true
yellowSquare.trailingAnchor.constraint(equalTo: subviewWrapper.trailingAnchor, constant: -100).isActive = true
yellowSquare.bottomAnchor.constraint(equalTo: subviewWrapper.bottomAnchor, constant: -100).isActive = true