I'm working on an Accessibility project where I have a segmentedController in the NavigationBar. Almost everything is working fine until the focus comes at the middle (2/3) SegmentedController. It won't speak the the accessibilityLabel..
See my code.
I'm using NSNotifications to let the 'UIAccessibilityPostNotification' know when to focus:
func chatLijst() {
let subViews = customSC.subviews
let lijstView = subViews.last as UIView
UIAccessibilityPostNotification(UIAccessibilityScreenChangedNotification, lijstView)
}
func berichtenLijst() {
let subViews = customSC.subviews
let messageView = subViews[1] as UIView
UIAccessibilityPostNotification(UIAccessibilityScreenChangedNotification, messageView)
}
func contactenLijst() {
let subViews = customSC.subviews
let contactenView = subViews.first as UIView
UIAccessibilityPostNotification(UIAccessibilityScreenChangedNotification, contactenView)
}
func setupSegmentedController(){
let lijst:NSString = "Lijst"
lijst.isAccessibilityElement = false
lijst.accessibilityLabel = "Lijst met gesprekken"
let bericht:NSString = "Bericht"
bericht.isAccessibilityElement = false
bericht.accessibilityLabel = "Bericht schrijven"
let contacten:NSString = "Contacten"
contacten.isAccessibilityElement = false
contacten.accessibilityLabel = "Contacten opzoeken"
let midden:CGFloat = (self.view.frame.size.width - 233) / 2
customSC.frame = CGRectMake(midden, 7, 233, 30)
customSC.insertSegmentWithTitle(lijst, atIndex: 0, animated: true)
customSC.insertSegmentWithTitle(bericht, atIndex: 1, animated: true)
customSC.insertSegmentWithTitle(contacten, atIndex: 2, animated: true)
customSC.selectedSegmentIndex = 0
customSC.tintColor = UIColor.yellowColor()
customSC.isAccessibilityElement = true
self.navigationController?.navigationBar.addSubview(customSC)
}
Fix
Strange enough I had to restructure the subViews array in the setup func and replace UIAccessibilityPostNotification object with the new segmentsView array.
func chatLijst() {
UIAccessibilityPostNotification(UIAccessibilityScreenChangedNotification, segmentsViews[0])
}
// Restructure subviews....
segmentsViews = [customSC.subviews[2], customSC.subviews[1], customSC.subviews[0]]
I'm using NSNotifications to let the 'UIAccessibilityPostNotification' know when to focus
Don't. That's a poor way to build a custom accessible control, and more importantly it can be confusing to the user. The screen changed notification doesn't just change focus, it also plays a specific sound that indicates to the user that the contents of the screen has changed.
Instead, I would recommend that you either make the subviews that you want appear as accessibility elements be accessibility elements with their own labels and traits and then rely on the OS to focus and activate them, or that you implement the UIAccessibilityContainer protocol in your custom control and then rely on the OS to focus and activate them.
Related
I want to copy one UIView to another view without making it archive or unarchive.
Please help me if you have any solution.
I tried with by making an extension of UIView as already available an answer on Stack over flow. But its crashing when I pass the view with pattern Image Background color.
The code related to my comment below:
extension UIView
{
func copyView() -> UIView?
{
return NSKeyedUnarchiver.unarchiveObjectWithData(NSKeyedArchiver.archivedDataWithRootObject(self)) as? UIView
}
}
I've just tried this simple code in a Playground to check that the copy view works and it's not pointing the same view:
let originalView = UIView(frame: CGRectMake(0, 0, 100, 50));
originalView.backgroundColor = UIColor.redColor();
let originalLabel = UILabel(frame: originalView.frame);
originalLabel.text = "Hi";
originalLabel.backgroundColor = UIColor.whiteColor();
originalView.addSubview(originalLabel);
let copyView = originalView.copyView();
let copyLabel = copyView?.subviews[0] as! UILabel;
originalView.backgroundColor = UIColor.blackColor();
originalLabel.text = "Hola";
originalView.backgroundColor; // Returns black
originalLabel.text; // Returns "Hola"
copyView!.backgroundColor; // Returns red
copyLabel.text; // Returns "Hi"
If the extension wouldn't work, both copyView and originalView would have same backgroundColor and the same would happen to the text of the labels. So maybe there is the possibility that the problem is in other part.
Original Post
func copyView(viewforCopy: UIView) -> UIView {
viewforCopy.hidden = false //The copy not works if is hidden, just prevention
let viewCopy = viewforCopy.snapshotViewAfterScreenUpdates(true)
viewforCopy.hidden = true
return viewCopy
}
Updated for Swift 4
func copyView(viewforCopy: UIView) -> UIView {
viewforCopy.isHidden = false //The copy not works if is hidden, just prevention
let viewCopy = viewforCopy.snapshotView(afterScreenUpdates: true)
viewforCopy.isHidden = true
return viewCopy!
}
I'm trying to implement 6 lines high description label and I want it to be focusable. Ideally that would mean extending UILabel class to make a custom component. I tried that by implementing canBecomeFocused and didUpdateFocusInContext but my UILabel doesn't seem to get any focus.
I also tried replacing UILabel with UIButton, but buttons aren't really optimised for this sort of thing. Also that would mean I'd need to change buttonType on focus from custom to plain.. and buttonType seems to be a ready-only property.
In reality I'd like to have exact same text label implemented by Apple in Apple TV Movies app. For movie description they have a text label that displays a few lines of text and a "more". When focused it looks like a button (shadows around) and changed background color. When tapped - it opens up a modal window with entire movie description.
Any suggestions? Or maybe someone has already implemented this custom control for tvOS? Or event better - there is a component from Apple that does this and I'm missing something.
P.S: Swift solution would be welcome :)
Ok, answering my own question :)
So it appears that some some views are "focusable" on tvOS out-of-the-box, and other have to be instructed to do so.
I finally ended up using UITextView, which has a selectable property, but if not one of these focusable views by default. Editing of TextView has to be disabled to make it look like UILabel. Also, currently there is a bug which prevents you from using selectable property from Interface Builder but works from code.
Naturally, canBecomeFocused() and didUpdateFocusInContext had to be implemented too. You'll also need to pass a UIViewController because UITextView is not capable of presenting a modal view controller. Bellow is what I ended up creating.
class FocusableText: UITextView {
var data: String?
var parentView: UIViewController?
override func awakeFromNib() {
super.awakeFromNib()
let tap = UITapGestureRecognizer(target: self, action: "tapped:")
tap.allowedPressTypes = [NSNumber(integer: UIPressType.Select.rawValue)]
self.addGestureRecognizer(tap)
}
func tapped(gesture: UITapGestureRecognizer) {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
if let descriptionView = storyboard.instantiateViewControllerWithIdentifier("descriptionView") as? DescriptionViewController {
if let view = parentView {
if let show = show {
descriptionView.descriptionText = self.data
view.modalPresentationStyle = UIModalPresentationStyle.OverFullScreen
view.presentViewController(descriptionView, animated: true, completion: nil)
}
}
}
}
override func canBecomeFocused() -> Bool {
return true
}
override func didUpdateFocusInContext(context: UIFocusUpdateContext, withAnimationCoordinator coordinator: UIFocusAnimationCoordinator) {
if context.nextFocusedView == self {
coordinator.addCoordinatedAnimations({ () -> Void in
self.layer.backgroundColor = UIColor.blackColor().colorWithAlphaComponent(0.2).CGColor
}, completion: nil)
} else if context.previouslyFocusedView == self {
coordinator.addCoordinatedAnimations({ () -> Void in
self.layer.backgroundColor = UIColor.clearColor().CGColor
}, completion: nil)
}
}
}
As for making a UILabel focusable:
class MyLabel: UILabel {
override var canBecomeFocused: Bool {
return true
}
override func didUpdateFocus(in context: UIFocusUpdateContext, with coordinator: UIFocusAnimationCoordinator) {
super.didUpdateFocus(in: context, with: coordinator)
backgroundColor = context.nextFocusedView == self ? .blue:.red
}
}
IMPORTANT!!!
As stated on the apple developer portal:
The value of this property is true if the view can become focused; false otherwise.
By default, the value of this property is false. This property informs the focus engine if a view is capable of being focused. Sometimes even if a view returns true, a view may not be focusable for the following reasons:
The view is hidden.
The view has alpha set to 0.
The view has userInteractionEnabled set to false.
The view is not currently in the view hierarchy.
Use a collection view with just one cell and add transform to cell and change cell background color in didUpdateFocusInContext when focus moves to cell.
override func didUpdateFocusInContext(context: UIFocusUpdateContext, withAnimationCoordinator coordinator: UIFocusAnimationCoordinator) {
coordinator.addCoordinatedAnimations({
if self.focused {
self.transform = CGAffineTransformMakeScale(1.01, 1.01)
self.backgroundColor = UIColor.whiteColor()
self.textLabel.textColor = .blackColor()
}
else {
self.transform = CGAffineTransformMakeScale(1, 1)
self.backgroundColor = UIColor.clearColor()
self.textLabel.textColor = .whiteColor()
}
}, completion: nil)
}
As an additional step you could try to extract the color of the image if you are using the image as background like iTunes and use that for Visual effect view behind the cell.
Also you can apply transform to the collectionView in the video controller to make it look like in focus
You can use system button, and set the background image in storyboard to an image that contains the color you would like
I am trying to make UIAlertController that looks like this:
How can we customize the UIAlertController to get the result something same as this picture ?
What you are trying to do is a popover, for current versions of iOS you can achieve the same effect for both iPad and iPhone.
1.- Start by building your design on Storyboard or a xib. and then reference it.
2.- then present it as a popover.
3.- maybe you will want to implement popoverdelegates to avoid wrong positions when rotating the device.
for example:
private static func presentCustomDialog(parent: UIViewController) -> Bool {
/// Loads your custom from its xib or from Storyboard
if let rateDialog = loadNibForRate() {
rateDialog.modalPresentationStyle = UIModalPresentationStyle.Popover
rateDialog.modalTransitionStyle = UIModalTransitionStyle.CrossDissolve
let x = parent.view.center
let sourceRectX : CGFloat
let maximumDim = max(UIScreen.mainScreen().bounds.height, UIScreen.mainScreen().bounds.width)
if maximumDim == 1024 { //iPad
sourceRectX = x.x
}else {
sourceRectX = 0
}
rateDialog.popoverPresentationController?.sourceView = parent.view
rateDialog.popoverPresentationController?.permittedArrowDirections = UIPopoverArrowDirection.allZeros
rateDialog.popoverPresentationController?.sourceRect = CGRectMake(sourceRectX, x.y, 0, 0)
rateDialog.popoverPresentationController?.popoverLayoutMargins = UIEdgeInsetsMake(0, 0, 0, 0)
rateDialog.popoverPresentationController?.delegate = parent
rateDialogParent = parent
dispatch_async(dispatch_get_main_queue(), {
parent.presentViewController(rateDialog, animated: true, completion: nil)
})
return true
}
return false
}
Update: to achieve, point 3... on your parent UIViewController.
public class MyParentViewController: UIViewController, UIPopoverPresentationControllerDelegate {
/**
This function guarantees that the CustomDialog is always centered at parent, it locates the Dialog view
*/
public func popoverPresentationController(popoverPresentationController: UIPopoverPresentationController, willRepositionPopoverToRect rect: UnsafeMutablePointer<CGRect>, inView view: AutoreleasingUnsafeMutablePointer<UIView?>) {
let x = popoverPresentationController.presentingViewController.view.center
let newRect = CGRectMake(x.x, x.y, 0, 0)
rect.initialize(newRect)
}
}
I did the custom popup windows as #Hugo posted, after a while i found a library that is done in a very neat and magnificent way which can be used to implement custom popup views with less effort:
here is the link for the library on Github:
https://github.com/m1entus/MZFormSheetPresentationController
It is written in Objective c, as well as there is swift example included in the library's samples.
to include it into swift project you will need to use something called Bridging-header
Good morning everyone,
I am a newbie Swift developer and I am facing the following problem implementing an exercise I am dealing with.
I have a collection view with collection cells displaying images I have imported in XCODE; when I tap with the finger on the screen I would like to replace the image currently being display with another one that i have also imported, and animate this replacement.
I am implementing the UITapLongPressureRecognizer method but i am getting confused on which state to implement for the recognizer, just to replace the first image view with the one I want to be shown when I tap the screen to scroll up-down.
As you can see from the code below the two recognizer I think should be more appropriate to be implemented are the "Begin" and "Ended".
My problem is that when the state .Begin starts I don't know how to animate the replacement of one image view with another and so when the state is .Ended I don't know how to replace the second image with the first one and animate the replacement (I want it to be like for example a Modal segue with "Cross Dissolve" transition).
Thank you in advance for your kindness and patience.
class MainViewController: UICollectionViewController {
var fashionArray = [Fashion]()
private var selectedIndexPath: NSIndexPath?
override func viewDidLoad() {
super.viewDidLoad()
selectedIndexPath = NSIndexPath()
//Register the cell
let collectionViewCellNIB = UINib(nibName: "CollectionViewCell", bundle: nil)
self.collectionView!.registerNib(collectionViewCellNIB, forCellWithReuseIdentifier: reuseIdentifier)
//Configure the size of the image according to the device size
let layout = collectionViewLayout as! UICollectionViewFlowLayout
let bounds = UIScreen.mainScreen().bounds
let width = bounds.size.width
let height = bounds.size.height
layout.itemSize = CGSize(width: width, height: height)
let longPressRecogn = UILongPressGestureRecognizer(target: self, action: "handleLongPress:")
collectionView!.addGestureRecognizer(longPressRecogn)
}
func handleLongPress(recognizer: UILongPressGestureRecognizer){
var cell: CollectionViewCell!
let location = recognizer.locationInView(collectionView)
let indexPath = collectionView!.indexPathForItemAtPoint(location)
if let indexPath = indexPath {
cell = collectionView!.cellForItemAtIndexPath(indexPath) as! CollectionViewCell
}
switch recognizer.state {
case .Began:
cell.screenTapped = false
case .Ended:
cell.screenTapped = false
default:
println("")
}
}
First of all, I suggest you to use UITapGestureRecognizer instead of long press. Because, as far as I understand, you only tap once instead of pressing for a time.
let tapRecognizer = UITapGestureRecognizer(target: self, action:Selector("tapped:"))
collectionView.addGestureRecognizer(tapRecognizer)
And when the user tapped, you can use UIView animations to change the image. You can check the Example II from the following link to get insight about animations.
http://www.appcoda.com/view-animation-in-swift/
I'm using a UITextView inside a UIPageViewController, and I want to determine the font size based on the size class of the device.
The first slide of the page view is loaded in ViewDidLoad like so (viewControllerAtIndex(0)):
override func viewDidLoad() {
super.viewDidLoad()
//Some unrelated code here
// Page View Controller for Questions Slider
questionPageVC = storyboard?.instantiateViewControllerWithIdentifier("QuestionPageView") as? UIPageViewController
questionPageVC!.dataSource = self;
questionPageVC!.delegate = self;
let startingViewController : QuestionContentViewController = viewControllerAtIndex(0) as QuestionContentViewController
var viewControllers = [startingViewController]
questionPageVC!.setViewControllers(viewControllers, direction: .Forward, animated: true, completion: nil)
let sliderHeight = view.frame.size.height * 0.5
questionPageVC!.view.frame = CGRectMake(20, 70,
view.frame.size.width-40, sliderHeight)
addChildViewController(questionPageVC!)
view.addSubview(questionPageVC!.view!)
questionPageVC?.didMoveToParentViewController(self)
var pageControl : UIPageControl = UIPageControl.appearance()
pageControl.pageIndicatorTintColor = UIColor.lightGrayColor()
pageControl.currentPageIndicatorTintColor = UIColor.blackColor()
pageControl.backgroundColor = UIColor.whiteColor()
// Some more code here
}
And then, in viewControllerAtIndex:
private func viewControllerAtIndex(index: Int) -> QuestionContentViewController {
var pcvc : QuestionContentViewController = storyboard?.instantiateViewControllerWithIdentifier("QuestionContentView") as! QuestionContentViewController
var fontSize = ""
if (view.traitCollection.horizontalSizeClass == UIUserInterfaceSizeClass.Compact) {
fontSize = "20"
} else {
fontSize = "28"
}
pcvc.questionString = TextFormatter(string: fontSize + questionsArray[index]).formattedString
pcvc.questionIndex = index
return pcvc
}
The problem is that the very first slide, which was called in viewDidLoad, always uses the font size in the "else" clause.
If I print view.traitCollection.horizontalSizeClass, for that first slide, I get 0 (UIUserInterfaceSizeClassUnspecified), for subsequent slides, I get the correct size.
I tried moving the whole thing to "viewWillAppear", and then weird things happen to the UIPageViewController (an extra slide with the wrong size text behind the other slides)
The problem is that viewDidLoad is too soon to be asking about a view's trait collection. This is because the trait collection of a view is a feature acquired from the view hierarchy, the environment in which it finds itself. But in viewDidLoad, the view has no environment: it is not in in the view hierarchy yet. It has loaded, meaning that it exists: the view controller now has a view. But it has not been put into the interface yet, and it will not be put into the interface until viewDidAppear:, which comes later in the sequence of events.
However, the view controller also has a trait collection, and it does have an environment: by the time viewDidLoad is called, the view controller is part of the view controller hierarchy. Therefore the simplest (and correct) solution is to ask for the traitCollection of self, not of view. Just say self.traitCollection where you now have view.traitCollection, and all will be well.
(Your solution, asking the screen for its trait collection, may happen to work, but it is not reliable and is not the correct approach. This is because it is possible for the parent view controller to alter the trait collection of its child, and if you bypass the correct approach and ask the screen, directly, you will fail to get the correct trait collection.)
I found that if I use the main screen's traitCollection, instead of the current view, I get the correct size class:
if (UIScreen.main.traitCollection.horizontalSizeClass == .compact) {
fontSize = "20"
} else {
fontSize = "28"
}
You will be better off moving that code to the viewWillAppear method, as in the viewDidLoad the ViewController's view has not been added to the hierarchy yet, and you might get an empty trait collection.
In my case I needed my view to know about the horizontalSizeClass so accessing the UIScreen traitCollection was tempting but not encouraged, so I had something like this:
override func layoutSubviews() {
super.layoutSubviews()
print("\(self.traitCollection.horizontalSizeClass.rawValue)")
switch self.traitCollection.horizontalSizeClass {
case .regular, .unspecified:
fontSize = 28
case .compact:
fontSize = 20
}
}
override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
super.traitCollectionDidChange(previousTraitCollection)
print("\(self.traitCollection.horizontalSizeClass.rawValue)")
guard let previousTraitCollection = previousTraitCollection else { return }
if self.traitCollection.horizontalSizeClass != previousTraitCollection.horizontalSizeClass {
layoutIfNeeded()
}
}
I took a hint from this Apple Technical Q&A and used viewWillLayoutSubviews instead of viewDidLoad/viewWillAppear.