I'm trying to make a set of UILabels bold, and figured it could be done with something like a CSS class. The only way I thought of though is subclassing UILabel and adding it as a Custom Class to each label:
import UIKit
class BoldLabel: UILabel {
override internal var font: UIFont? {
get {
return UIFont.boldSystemFontOfSize(16.0)
}
}
}
But this gives an error "Getter for 'font' with Objective-C selector 'font' conflicts with getter for 'font' from superclass 'UILabel' with the same Objective-C selector". So is there a way to do it like this, or a different way to easily make a bunch of labels' fonts bold?
import UIKit
class BoldLabel: UILabel {
//This method is call when you affect this class to a UILabel in your STORYBOARD
required init?(coder aDecoder: NSCoder) {
super.init(coder:aDecoder)
self.setup()
}
//This method is call when you programatically create an instance of this UILabel class
override init(frame:CGRect) {
super.init(frame:frame)
self.setup()
}
func setup() {
//All custom properties of this label class here
self.font = UIFont.boldSystemFontOfSize(28)
}
}
Results with UILabels from storyboard :
Related
now I'm trying to make a custom NavBarAppearance class that subclassing UINavigationBarAppearance, since I have the following same code's in my view controllers.
let appearance = UINavigationBarAppearance()
appearance.configureWithOpaqueBackground()
appearance.backgroundColor = .red // this varys in each vc
appearance.shadowColor = .clear // this also varys in each vc
So, I made a class for the custom UINavigationBarAppearance like below.
import UIKit
class OLNavigationBarAppearance: UINavigationBarAppearance {
override init(barAppearance: UIBarAppearance) {
super.init(barAppearance: barAppearance)
}
required init(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
init(backgroundColor: UIColor, shadowColor: UIColor) {
super.init(barAppearance: ) // <- not sure what to put in here...
self.backgroundColor = backgroundColor
self.shadowColor = shadowColor
}
}
I want to make the custom BarAppearance class to take two parameters, backgroundColor and shadowColor, and tried calling super.init() in the custom initializer, and got the error, Must call a designated initializer of the superclass 'UIBarAppearance'.
So, my question is how to find out the designated initializer of the superclass XYZ.
I looked up the UIBarAppearance documentation and there were four initializers.
But first, how do people know which one is the "required" initializer?
I'm pretty new to coding. Im not sure if an IBOutlet (button, text field, etc) ctrl-dragged from a xib should go in the xib's NSView class or in the view controller which has the NSView added as a subview.
I've been playing around with this for a while, learning as I go. I'm stuck on wondering if I have the code structured correctly. This is for MacOS so resources are limited and often dated. I'd assume that an outlet added for a button, for example, would go in the controller as views should be "dumb". If I try that the actions always have "action" set automatically and type as Any as a default - not what I'm used to seeing. I suspect this may have something to do with the class set for the file's owner and the class set for the view in IB. If anyone can outline the best way to handle this that would be fantastic, thank you!
The view that loads the xib:
class View4: NSView {
#IBOutlet weak var view: View4!
override init(frame frameRect: NSRect) {
super.init(frame: frameRect)
Bundle.main.loadNibNamed("View4", owner: self, topLevelObjects: nil)
self.frame = self.bounds
self.wantsLayer = true
self.translatesAutoresizingMaskIntoConstraints = false
self.layer?.backgroundColor = NSColor.purple.cgColor
self.roundedCorners(on: self)
// add xib to custom NSView subclass
self.addSubview(self.view)
}
required init?(coder: NSCoder) {
super.init(coder: coder)
}
override func draw(_ dirtyRect: NSRect) {
super.draw(dirtyRect)
// Drawing code here.
}
}
The corresponding ViewController:
class View4Controller: NSViewController {
override func loadView() {
print("View4Controller.loadView")
self.view = NSView()
}
override func viewDidLoad() {
super.viewDidLoad()
// Do view setup here.
print("View4Controller.viewDidLoad")
self.view = View4()
}
}
The idea of an outlet is to have a reference to an object that is outside of your code created. The concept is great for prototyping, but tends to become hard to manage as a project grow.
If you class is the class, then it can refer to itself. („self“ in swift or „this“ in c++) You don't need an outlet in this case.
The outlet is normally used by controller that need to maintain the view. The concept is a alternative to creating and configuring the view manually.
I'm writing nib-less views in which I use autolayout for all my layout logic. I find myself having to turn off autoresizing with every view I instantiate. My code is littered with a lot of these:
view.translatesAutoresizingMaskIntoConstraints
Ideally I'd like to just
extension UIView/NSView {
override var translatesAutoresizingMaskIntoConstraints: Bool = false
}
and get it over with once and for all, but extensions can't override stored properties.
Is there some other simple way to switch off autoresizing for good?
Well just a suggestion since its annoying to always set that to false, just setup a function with all the shared setups for the UIView and call it every time,
its saves time and its kinda less annoying than trying and setting the values each time,
extension UIView {
func notTranslated() {
self.translatesAutoresizingMaskIntoConstraints = false
//Add any additional code.
}
}
//Usage
let view = UIView()
view.notTranslated()
You can't override this constraints properties because the UIView maybe declared in the IB
translatesAutoresizingMaskIntoConstraints according to apple.
By default, the property is set to true for any view you programmatically create. If you add views in Interface Builder, the system automatically sets this property to false.
imagine if you could override that from an extension that would lead to some conflicts if there was other UIView's that's have the opposite value True || false, so in my opinion:
Apple did this to prevent any conflicts with the views constrains, therefore if you don't like to write it every time just wrap it up in a function.
Please if anyone have additional information, don't hesitate to contribute.
UPDATE: I found this cool answer that could also work, check out the code below.
class MyNibless: UIView {
//-----------------------------------------------------------------------------------------------------
//Constructors, Initializers, and UIView lifecycle
//-----------------------------------------------------------------------------------------------------
override init(frame: CGRect) {
super.init(frame: frame)
didLoad()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
didLoad()
}
convenience init() {
self.init(frame: CGRect.zero)
}
func didLoad() {
//Place your initialization code here
//I actually create & place constraints in here, instead of in
//updateConstraints
}
override func layoutSubviews() {
super.layoutSubviews()
//Custom manually positioning layout goes here (auto-layout pass has already run first pass)
}
override func updateConstraints() {
super.updateConstraints()
//Disable this if you are adding constraints manually
//or you're going to have a 'bad time'
//self.translatesAutoresizingMaskIntoConstraints = false
translatesAutoresizingMaskIntoConstraints = false
//Add custom constraint code here
}
}
var nibless: UIView = MyNibless()
//Usage
nibless.updateConstraints()
print(nibless.translatesAutoresizingMaskIntoConstraints) //false
So simply just create MyNibless instance as UIView and this also open big door to customizations too
I have a slider:NSSlider and valueLabel:NSTextField, and I'm wondering what's the proper way to make it accessible for VoiceOver users.
First I connected a send action for slider to sliderChanged function to update valueLabel.
valueLabel.stringValue = String(slider.integerValue)
VoiceOver reads the label correctly, but it reads the slider in percentage. To fix this, I changed sliderChanged function to setAccessibilityValueDescription.
slider.setAccessibilityValueDescription(String(slider.integerValue))
Now VoiceOver correctly reads the value for the slider. However, it sees both valueLabel and slider, so it's redundant.
I tried valueLabel.setAccessibilityElement(false), but VoiceOver doesn't seem to ignore.
Could someone advise what would be the proper way to implement this? Thanks!
The best way to do this is to create a custom "ContainerView" class (which inherits from UIView) that contains the label and the slider, make the ContainerView an accessibilityElement, and set its accessibilityTraits to "adjustable." By creating a ContainerView that holds both the valueLabel and the slider, you remove the redundancy that is present in your current implementation, while not affecting the layout or usability of the slider/valueLabel for a non-VoiceOver user. This answer is based on this video, so if something is unclear or you want more in-depth info, please watch the video!
Setting a view's UIAccessibilityTraits to be "Adjustable" allows you to use its functions accessibilityIncrement and accessibilityDecrement, so that you can update whatever you need to (slider, textfield, etc). This trait allows any view to act like a typical adjustable (without having to add UIGestureRecognizers or additional VoiceOver announcements).
I posted my code below for convenience, but it is heavily based on the video that I linked to above. (I personally am an iOS developer, so my Swift code is iOS-based)
Note -- I had to override the "accessibilityValue" variable -- this was to make VoiceOver announce changes in the slider whenever the user swiped up or down.
My ContainerView class contains the following code:
class ContainerView: UIView {
static let LABEL_TAG = 1
static let SLIDER_TAG = 2
var valueLabel: UILabel {
return self.viewWithTag(ContainerView.LABEL_TAG) as! UILabel
}
var slider: UISlider {
return self.viewWithTag(ContainerView.SLIDER_TAG) as! UISlider
}
override var accessibilityValue: String? {
get { return valueLabel.text }
set {}
}
override var isAccessibilityElement: Bool {
get { return true }
set { }
}
override var accessibilityTraits: UIAccessibilityTraits {
get { return UIAccessibilityTraitAdjustable }
set { }
}
override init(frame: CGRect) {
super.init(frame: frame)
valueUpdated()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
valueUpdated()
}
func valueUpdated() {
valueLabel.text = String(slider.value)
slider.sendActions(for: .valueChanged)
}
override func accessibilityIncrement() {
super.accessibilityIncrement()
slider.setValue(slider.value + 1, animated: true)
valueUpdated()
}
override func accessibilityDecrement() {
super.accessibilityDecrement()
slider.setValue(slider.value - 1, animated: true)
valueUpdated()
}
}
Hope this helps!
I have created a subclass of UILabel called MyUILabel. The only thing changed is the font and font-size. It appears as expected when I run the app. However, the in the Storyboard, the default UILabel is showed. Is there any way to make Storyboards show the font and font-size from my subclass?
MyUILabel:
public class MyUILabel : UILabel {
required public init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
self.font = UIFont(name: Constants.DefaultFont, size: 30)
}
}
You could make it #IBDesignable, and then implement prepareForInterfaceBuilder:
#IBDesignable
public class MyUILabel: UILabel {
public override func awakeFromNib() {
super.awakeFromNib()
configureLabel()
}
public override func prepareForInterfaceBuilder() {
super.prepareForInterfaceBuilder()
configureLabel()
}
func configureLabel() {
font = UIFont(name: Constants.DefaultFont, size: 40)
}
}
Note, IB didn't like it when I implemented init(coder:), so I moved it into awakeFromNib.
Also note that when you make an #IBDesignable class, Apple advises that you create a separate target (e.g. "File" - "New" - "Target..." - "Cocoa Touch Framework") for this designable class. For more information, see WWDC 2014 video What’s New in Interface Builder.