Applying an extension to only certain instances of UIButton - ios

I have a UIButton extension to make some of my buttons have a round shape:
extension UIButton {
override open var intrinsicContentSize: CGSize {
let originalContentSize = super.intrinsicContentSize
let height = originalContentSize.height + 5
layer.cornerRadius = height / 2
layer.masksToBounds = true
return CGSize(width: originalContentSize.width + 35, height: height)
}
}
This works as intended for the buttons within my views. However, I also have some buttons in my navigation bars, which have been affected by this extension and now appear in their containers with extra padding that is rather unsightly.
This is how I usually create my navigation bar buttons:
private func navBarButton() -> UIBarButtonItem {
let button = UIBarButtonItem(image: UIImage(named: "x"), style: .plain, target: self, action: #selector(x))
button.tintColor = .black
return button
}
Before I added my extension to the UIButton class, my navbar buttons used to look like this:
Now, they look like this:
which I do not want. How do I make my navbar buttons go back to what they looked like before adding my extension?

Change your extension from an override to a static function so it only happens when you explicitly instantiate one:
extension UIButton {
static func createAsRound(size: CGSize) -> UIButton {
let button = UIButton(type: .system)
button.frame = CGRect(origin: CGPoint.zero, size: size)
button.layer.cornerRadius = size.height/2
button.layer.masksToBounds = true
return button
}
}
Usage:
let myButton = UIButton.createAsRound(size: CGSize(width: 40, height: 40))
EDIT. If you are using auto layout:
In your extension, add to 'createAsRound`
button.translatesAutoresizingMaskIntoConstraints = false
Then add another method that will only be called as needed:
func makeRound() {
button.layer.cornerRadius = self.frame.height/2
self.setNeedsDisplay()
}
This edit is untested code. I'll edit as needed. (The first code I've used many times and with auto layout).
Obviously the one line of code to add is, well, actually just a convenience. Once you set the auto mask flag you're telling iOS to use auto layout. Setting a "frame" versus setting explicit origin/size constraints - particularly if using layout anchors can be done in the extension as long as you've already instantiated the button's superview.
Dynamically changing the size? Once you glean the UIViewController hierarchy, it should be simple. One like place is viewDidLayoutSubviews where the instantiated UIButton should have had auto layout compute it's frame... at which point you just make it round.
This may not exactly fit your needs, but it should be a good start to creating exactly a round UIButton only when you want to.

Why not to use an explicit class that will do exactly what you need?
class RoundedButton: UIButton {
open override var intrinsicContentSize: CGSize {
let originalContentSize = self.intrinsicContentSize
let height = originalContentSize.height + 5
layer.cornerRadius = height / 2
layer.masksToBounds = true
return CGSize(width: originalContentSize.width + 35, height: height)
}
}

Related

UIView animation snaps into updated bounds before animation is done

Problem:
I am trying to create my own custom search field with a desired growing animation (if you click on it), and a shrinking animation when the user taps out.
The animation behaves weirdly since it moves out of the right screen bounds when shrinking, even though the text field/search bar's right anchor is not modified.
Like so:
Notice how the right side of the search bar briefly moves outside of the visible screen bounds during the animation.
Expected behavior:
The search bar should smoothly grow/shrink without moving the right edge position of the text field, i.e. have the right anchor stay pinned.
What you see in above gif is built using the following code (by subclassing a UITextField):
public class MySearchBar: UITextField {
private var preAnimationWidth: NSLayoutConstraint?
private var postAnimationWidth: NSLayoutConstraint?
public override init(frame: CGRect) {
super.init(frame: frame)
self.backgroundColor = Theme.GRAY800
self.borderStyle = .roundedRect
self.layer.masksToBounds = true
self.clipsToBounds = true
self.autocorrectionType = .no
self.font = FontFamily.ProximaNova.regular.font(size: 16)
self.textColor = .white
self.attributedPlaceholder = NSAttributedString(string: "Search", attributes: [.foregroundColor : Theme.GRAY400, .font: FontFamily.ProximaNova.regular.font(size: 16)])
// some further appearance configurations
}
public func setupGrowAnimation(initialWidth: NSLayoutConstraint, grownWidth: NSLayoutConstraint, height: CGFloat) {
preAnimationWidth = initialWidth
postAnimationWidth = grownWidth
self.layer.borderWidth = 0
self.layer.cornerRadius = height / 2
}
// growButton is called when the textfield becomes active, i.e. the user taps on it.
public func growButton() {
guard let preAnimationWidth = preAnimationWidth, let postAnimationWidth = postAnimationWidth else { return }
UIView.animate(withDuration: 0.2) {
preAnimationWidth.isActive = false
postAnimationWidth.isActive = true
self.layer.borderColor = Theme.GRAY600.cgColor
self.layer.borderWidth = 2
self.layer.cornerRadius = 8
self.layoutIfNeeded()
}
}
// shrinkButton is called whenever the textfield resigns its first responder state, i.e. the user clicks out of it.
public func shrinkButton() {
guard let preAnimationWidth = preAnimationWidth, let postAnimationWidth = postAnimationWidth else { return }
UIView.animate(withDuration: 0.2) {
postAnimationWidth.isActive = false
preAnimationWidth.isActive = true
self.layer.borderWidth = 0
self.layer.borderColor = .none
self.layer.cornerRadius = self.frame.height / 2
self.layoutIfNeeded()
}
}
}
And this is how the search bar is initialized in my viewDidLoad:
override func viewDidLoad() {
let containerView = UIView()
let searchBar = MySearchBar()
searchBar.addTarget(self, action: #selector(searchBarChangedEntry(_:)), for: .editingChanged)
searchBar.addTarget(self, action: #selector(searchBarEndedEditing(_:)), for: .editingDidEnd)
searchBar.translatesAutoresizingMaskIntoConstraints = false
let initialWidth = searchBar.widthAnchor.constraint(equalToConstant: 100)
let expandedWidth = searchBar.widthAnchor.constraint(equalTo: containerView.widthAnchor, constant: -32)
searchBar.setupGrowAnimation(initialWidth: initialWidth, grownWidth: expandedWidth, height: 44)
containerView.addSubview(searchBar)
stackView.insertArrangedSubview(containerView, at: 0)
NSLayoutConstraint.activate([
containerView.heightAnchor.constraint(equalToConstant: 44),
containerView.widthAnchor.constraint(equalTo: self.stackView.widthAnchor),
searchBar.heightAnchor.constraint(equalTo: containerView.heightAnchor),
initialWidth,
searchBar.rightAnchor.constraint(equalTo: containerView.rightAnchor, constant: -16)
])
self.stackView.setCustomSpacing(12, after: containerView)
}
The search bar is part of a container view which, in turn, is the first (top) arranged subview of a stack view covering the entire screen's safeAreaLayout rectangle
What I already tried:
I have to perform the animation using constraints, and I've tried to animate it without using the width anchor (e.g. by animating the leftAnchor's constant). Nothing worked so far.
Upon googling, I couldn't really find anything helpful that would help me find a solution to this problem, which is why I am trying my luck here.
I do have to admit that I am not proficient with animations of iOS at all - so please bear with me if this is a simple mistake to fix.
So, why does the search bar behave that way? And how can I fix this?
A little tough to say, because the code you posted is missing a lot of information (for example, you don't show the creation of the stackView, nor where its being added to the view hierarchy).
However, you might fix your issue with this simple change...
In both your growButton() and shrinkButton() funcs, change this line in the animation block:
self.layoutIfNeeded()
to this:
self.superview?.layoutIfNeeded()
Edit - a little explanation...
To animate constraint changes, we want to call .layoutIfNeeded() on the top-most view that will be affected.
When calling:
UIView.animate(withDuration: 0.5) {
self.someView.layoutIfNeeded()
}
we're telling auto-layout to calculate the changes and then generate and run an animation... but only for someView and its subviews.
If our action is going to affect someView.superview - or, for example, the constraint change is going to move/size a sibling of someView or a sibling of someView.superview, we haven't told auto-layout to include those views in its layout calculations.
I expect there are specific implementations / layout hierarchies where one would want to specifically exclude some views from the layout / animation... but...
Personally, I do this:
UIView.animate(withDuration: 0.5) {
self.view.layoutIfNeeded()
}
because the constraint I want to animate might be on a subview deep in the view hierarchy - and could have 4 or 5 or 6 etc superviews - all of which could be affected by the change.

How do I prevent Keyboard from adding its own height constraint when using view as inputAccessoryView

I'm trying to use a custom view as an accessory view over the keyboard, for various reasons, in this case, it is much preferred over manual keyboard aligning because of some other features.
Unfortunately, this is a dynamic view that defines its own height. The constraints all work fine outside of the context of an accessoryView without errors, and properly resizing
When added as a keyboardAccessoryView it seems to impose a height of whatever the frame is at the time and break other height constraints
It appears as:
"<NSLayoutConstraint:0x600003e682d0 '_UIKBAutolayoutHeightConstraint' Turntable.ChatInput:0x7fb629c15050.height == 0 (active)>"
(where 0 would correspond to whatever height had been used at initialization
It is also labeled accessoryHeight which should make it easy to remove, but unfortunately, before I can do this, I'm getting unsatisfiable constraints and the system is tossing my height constraints
Tried:
in the inputAccessoryView override, I tried to check for the constraints and remove it, but it doesn't exist at this time
setting translatesAutoresizing...Constraints = false
tl;dr
Using a view as a KeyboardAccessoryView is adding its own height constraint after the fact, can I remove this?
Looks like keyboard doesn't like inputAccessoryView with height constraint. However you still can have inputAccessoryView with dynamic height by using frame (it is still possible to use constraints inside your custom inputAccessoryView).
Please check this example:
import UIKit
final class ViewController: UIViewController {
private let textField: UITextField = {
let view = UITextField()
view.frame = .init(x: 100, y: 100, width: 200, height: 40)
view.borderStyle = .line
return view
}()
private let customView: UIView = {
let view = UIView()
view.backgroundColor = .red
view.frame.size.height = 100
view.autoresizingMask = .flexibleHeight // without this line height won't change
return view
}()
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(textField)
textField.inputAccessoryView = customView
textField.becomeFirstResponder()
DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
self.customView.frame.size.height = 50
self.textField.reloadInputViews()
}
}
}

Swift UITableViewCell Shadow not appearing

I am trying to create custom table view cell which works fine in my other UIViewControllers. However, in one of my controllers, the shadow is not growing, I can barely see the shadow.
Here is an image of the shadow being shown in red, you can see it is barely visible.
My cell has a UIView added inside the contentView to creating floating cell effects - the same code and same storyboard layouts are being used across my controllers but this is the only table view where the shadow issue is occurring - so I must be missing something.
My addShadow extension:
extension UIView {
func addShadow(offset: CGSize, color: UIColor, radius: CGFloat, opacity: Float) {
layer.masksToBounds = false
layer.shadowOffset = offset
layer.shadowColor = color.cgColor
layer.shadowRadius = radius
layer.shadowOpacity = opacity
}
}
My awakeFromNib on the custom cell:
:: cellContentView is my UIView added to the base contentView of the cell.
override func awakeFromNib() {
super.awakeFromNib()
self.backgroundColor = .clear
self.selectionStyle = .none
cellContentView?.layer.masksToBounds = true
cellContentView?.round(corners: [.topLeft, .topRight, .bottomLeft, .bottomRight], radius: 10)
cellContentView?.addShadow(offset: CGSize(width: 40, height: 60), color: UIColor.red, radius: 10, opacity: 1)
cellContentView?.layer.shouldRasterize = true
}
Note: The .round is an extension being used on all my cells.
No matter what radius or offset I add for this shadow, it does not get bigger than the image. Also, none of my other cells in the their controllers require the shouldRasterize property to be set, but this does.
Does anyone know what is happening here?
Thanks :)
Edit
Strangely, if I add constraints around my view to keep the gaps large between my view and the cell content view, the background colour disappears - this is set to white in the storyboard.
You should call in the layoutSubviews method. because shadow should add after the view is uploaded
override func awakeFromNib() {
super.awakeFromNib()
//init methods
}
override public func layoutSubviews() {
super.layoutSubviews()
//Added shadow
self.reloadLayers()
}
private func reloadLayers() {
self.layer.cornerRadius = 5
self.addShadow(.TransactionCell)
}
I hope it helps
Content view will fill you cell, so you need to add shadow to view inside content view which has all your components inside it. Then add constraints to it with gap between that view and content view. Second, 40 and 60 properties for shadow is likely too large, when I said too large I mean unbelievable large, because gap between content views in cells are no more than 15 - 30 even less. so try it with much less values, while radius can remain 10 but you will see what value fit the best. If cell content view is your custom view just values will did the job if your view is not kind of transparent or any inside it, in that case it won't, and there is hard to fix that, I tried many libraries and custom codes and it is never ok.
squircleView.layer.cornerRadius = 40
squircleView.layer.cornerCurve = CALayerCornerCurve.continuous
squircleView.layer.shadowColor = UIColor.systemGray.cgColor
squircleView.layer.shadowOpacity = 0.7
squircleView.layer.shadowOffset = CGSize(width: 0, height: 0.5)
squircleView.layer.shadowRadius = 5

UITextField Left View Mode .never Not Working

I added a left view to my UITextField via:
customTextField.leftView = searchIconView
customTextField.leftViewMode = .always
However, I later need to remove that icon from my customTextField and make it look like the original. You would think that you could just do this and it would reset:
customTextField.leftView = nil
customTextField.leftViewMode = .never
This did not work. It got rid of my search icon, but the padding of the left view still acted like it was there. It just is this weird whitespace.
I figured out the answer to my own question:
I had to leave the customTextField.leftViewMode as .always once I had set it. Then, when I want to revert back to the original, I just set a new view for the Left View that is zero everything except has the original padding for the customTextField.
customTextField.leftView = UIView(frame: CGRect(origin: .zero, size: CGSize(width: customTextField.originalLeftPadding, height: 0)))
I get the original text field padding by subclassing UITextField for my customTextField, then I just hold onto the original left padding as a variable:
class CustomTextField : UITextField {
var originalLeftPadding: CGFloat = 0
override init(frame: CGRect) {
super.init(frame: frame)
originalLeftPadding = leftPadding
}
}

adding a constraint to a subview makes background color not display

So i am using a custom function to format an subview that I am adding to a UICollectionViewCell. It is from Brian Voong's public project here: https://github.com/purelyswift/facebook_feed_dynamic_cell_content/blob/master/facebookfeed2/ViewController.swift.
func addConstraintsWithFormat(format: String, views: UIView...) {
var viewsDictionary = [String: UIView]()
for (index, view) in views.enumerate() {
let key = "v\(index)"
viewsDictionary[key] = view
view.translatesAutoresizingMaskIntoConstraints = false
}
addConstraints(NSLayoutConstraint.constraintsWithVisualFormat(format, options: NSLayoutFormatOptions(), metrics: nil, views: viewsDictionary))
}
What is interesting, is that in my UICollectionView I add a SubView to a single cell, and set the background color to white. The background is white when I comment out the line which sets the background for the subview, and no background color is set when I uncomment out the line setting the visually formatted constraints for the subview.
Here are the two lines which clobber each other:
func chronicleOneClicked(sender: UIButton) {
point1view.backgroundColor = UIColor.whiteColor()
addSubview(point1view)
//When the below is commented the background of point1view disappears
//addConstraintsWithFormat("|-50-[v0]-50-|", views: point1view)
}
when I do print(subviews) i see that the UIView with the white background color is the highest in the view stack (top of the stack). When i print out subviews[subviews.count-1].backgroundColor I get the Optional(UIDeviceWhiteColorSpace 1 1) which is what I expect. it is strange because the color is not displayed.
I am not sure how to go about seeing what is happening behind the scenes to confirm that the background is being set at all in the latter case.
This all happens in a class for the UiCollectionViewCell which I am using as the class of one of my UICollectionView Cells which can be viewed in its entirety here:
https://gist.github.com/ebbnormal/edb79a15dab4797946e0d1f6905c2dd0
Here is a screen shot from both cases, the first case is where the line addConstraintsWithFormat is commented out, and the second case is where it is uncommented: The subview of point1subview is highlighted with a white background in the first case.
This is how I setup the views. It all happens in a class that overrides UICollectionViewCell
class myClass : UICollectionViewCell {
var chronicle: BrowsableChronicle? {
didSet{
//etc.
point1.addTarget(self, action: #selector(chronicleOneClicked(_:)), forControlEvents: UIControlEvents.TouchUpInside)
}
}
override init(frame: CGRect) {
super.init(frame: frame)
setupViews()
}
let point1 : PointButtonView = {
let pointView = PointButtonView(frame: CGRectMake(0, 0, 25, 25 ))
return pointView
}()
//NOTE here is where I create the view, whose background doesn't display
let point1view : UIView = {
let pointView = UIView(frame: CGRectMake( 0, 0, 200, 270))
pointView.backgroundColor = UIColor.whiteColor()
let title = UILabel(frame: CGRectMake(0, 0, 200, 21))
title.font = UIFont(name:"HelveticaNeue-Bold", size: 16.0)
pointView.addSubview(title)
let summary = UILabel(frame: CGRectMake(0, 0, 190, 260))
summary.lineBreakMode = NSLineBreakMode.ByWordWrapping
summary.numberOfLines = 4
summary.font = UIFont(name:"HelveticaNeue", size: 12.5)
pointView.addSubview(summary)
let button = UIButton(frame: CGRectMake(0, 200, 190, 30))
button.backgroundColor = UIColor(red:0.00, green:0.90, blue:0.93, alpha:1.0)
pointView.addSubview(button)
pointView.tag = 100
return pointView
}()
//NOTE: here is where I add the subview to the UICollectionViewCell view
func chronicleOneClicked(sender: UIButton){
addSubview(point1view)
addConstraintsWithFormat("H:|-20-[v0]-20-|", views: point1view)
//TODO anytime i add a constraint here the background color leaves!
print(subviews[subviews.count-1].backgroundColor) //Prints white
}
}
UPDATE: I thought maybe it was related to this issue :
UITableViewCell subview disappears when cell is selected
Where the UICollectionViewCell is selected, and therefore iOS automatically sets the backgroundColor to clear. The problem is, that I implemented this class extension of UIView to see when didSet is called on the backgroundColor and when it is set to clear, i set it to white. However, it only calls didSet on the backgroundColor once, when i first set the color of the view. Here is the code I used to override the UIView class:
class NeverClearView: UIView {
override var backgroundColor: UIColor? {
didSet {
print("background color is being set")
if backgroundColor == UIColor.clearColor() {
print("set to a clear color")
backgroundColor = UIColor.whiteColor()
}
}
}
}
The difference you are seeing is obviously caused by a view frame resulting in zero width or zero height.
Let's explain how the drawing system works.
Every view has a layer that draws its background color in its bounds, which are specified by the view frame. Then every subview is drawn. However, the subviews are not limited by the frame unless you set UIView.clipsToBounds to true.
What you are seeing means the a container view has a zero frame (either width or height) but its subviews have correct frame, therefore they are displayed correctly.
There are multiple reasons why this could happen, for example:
You are setting translatesAutoresizingMaskIntoConstraints to false to some system view (e.g. the content view of the UICollectionView).
You have a constraint conflict, resulting in some important constraint to be removed (you should see a warning).
You are missing some constraints. Specifically, I don't see you setting vertical constraints.
You should be able to debug the problem using the view debugger in Xcode. Just open your app, click the view debugger button and print the recursive description of the cell. You should see a frame that is zero.

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