I have a page where the elements are added to the view in below order:
Self.view
title (Label)
close (Button)
back (Button)
next (Button)
scrollview
The Voice Over dictation is set to start from the title, close, next, back, and then to the subviews of scrollview. It works as expected unless until I leave to another page and come back. Whenever this page is loaded again from another view, it starts dictating from title all over again, though the page's UI stays at where it was last left at.
The scrollview is set to scroll in horizontal direction and it has 10 subviews(questions) to mimic a pagination effect. On 4th and 9th pages, I have option to where it needs to present another controller A. When dismissing from the controller A, the Voice Over starts dictating from title instead of resuming from the last element active i.e the 4th page's question or its options. This is a mockup of the placement of UI elements where I have difficulty fixing Voice Over elements order.
horizontalScroller.accessibilityElements = [firstQuestion, secondQuestion, thirdQuestion, fourthQuestion, fifthQuestion, sixthQuestion, seventhQuestion, eigthQuestion, ninthQuestion, finalQuestion]
view.accessibilityElements = [titlelabelLabel, closebuttonButton, nextButton, backButton, horizontalScroller]
I assume it is because Voice Over is designed to start all over from the beginning each time it loads a page. But, in this case it would be quite confusing to a visually impaired user to go over same question, IMO. Any help in tweaking this to resume where it was last at, would be highly appreciated.
When your view appears you can check if VoiceOver is running with:
UIAccessibility.isVoiceOverRunning
If VoiceOver is running, you can use the following to make VoiceOver move to targetView:
UIAccessibility.post(notification: .layoutChanged, argument: targetView)
And if that doesn’t work:
UIAccessibility.post(notification: .screenChanged, argument: targetView)
Edit: posting the notifications after a delay is needed in some cases.
Related
I've implemented a custom dialog box in a game (showing options when the game is paused) by using a Container View in the main game's ViewController.
That Container View has a constraint to be centered vertically and I'm using that constraint to animate this custom dialog box.
The dialog box itself is an image of a wooden board on a pole with 4 buttons, each being an image I prepared. These buttons are arranged in a vertical Stack View which contains 2 horizontal Stack Views, each with 2 buttons, so they will be laid out nicely symmetrical.
All of the above is done in Interface Builder. So a segue was automatically added from the game's main ViewController to the new Pause Dialog View Controller.
In my game's main ViewController I move the Container View out of view by adding the following to my viewDidLoad():
dialogBoxYConstraint.constant -= (view.bounds.height)
Then when the user clicks on a PAUSE button which should show this dialog, the following code is running:
UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.5, options: .curveEaseInOut) {
self.dialogBoxYConstraint.constant += (self.view.bounds.height)
self.view.layoutIfNeeded()
}
}
So this code will bring the constraint's constant back to its original location and it will show the dialog box that I put inside the Container View.
When the user clicks on the PAUSE button all of this indeed happens and there's a nice animation with the wooden board and all 4 buttons fall into place and all buttons are clickable. Here's an image (disregard the small white buttons, these are temporary work-in-progress):
But, before that, before I click on the PAUSE button, I always see part of the buttons all the way on top. I see the lower 2 buttons completely and a bit of those above as in the following image:
As you can see, the wooden board isn't here, only the buttons, and when I do press the PAUSE button everything together correctly animates to the right place as in the 1st image.
(It's an AR app so you basically see my walls in the background, but that's irrelevant for this question).
Moreover, when the buttons are on top, they are not clickable.
Also, it doesn't matter if I change the constraint's constant to be even higher, say I do this:
dialogBoxYConstraint.constant -= (view.bounds.height + 500)
the buttons will always show at the same place.
And if I try to put this line in viewDidAppear then I can see the whole board with the buttons as in the first image for a second on a black background and then I get what you see in the 2nd image, which makes sense.
The above happens whether or not I've implemented the prepare(for segue: )
The segue itself is actually happening immediately as the main view is loaded, which is why I had to initially move it out of view.
As a test, I tried to set one button's isHidden to true in the Pause Dialog View Controller and then set it to false in the prepare(for segue: ), thinking that maybe that would do something, but the button remained hidden all the time.
(Side question: how should I perform such changes in this child View Controller only after the user presses the PAUSE button? Since the segue happens already from the start, I don't understand how to control such changes only later on by user action?)
I'm not sure what I'm doing wrong. Looks like a glitch, but, as always, I guess it's something I did.
I had assumed that moving the view's constraint should always move all of its contents together.
Anyone has any idea why the buttons are always there at the top?
I saw that there is a present(_:animated:completion:) method to present VC's. Should I be looking into this instead of animating the constraint as I did???
Posting this as an answer, as per the OP's comments...
It can be very difficult to debug layouts when UI element are "clear." Giving them background colors allows you to easily see the framing at run-time.
Also, Debug View Hierarchy can be very helpful, because you can inspect constraints (and even see hidden or out-of-bounds elements). Note that you may need to temporarily disable certain features - such as playing video or an active AR scene.
I am working on the IOS application, related to voice over, my Question is : When accessibility voice over was enabled how can i get the swipe gestures left, right, top and down, what re the function for detecting these in swift?
First of all, you need to let VoiceOver know that about your view (or another element). So if you are in a view controller, this should work: self.view.isAccessibilityElement = true
Second, you need to let VoiceOver know that your view will handle user interactions on its own: self.view.accessibilityTraits = UIAccessibilityTraitAllowsDirectInteraction. After that your view should start getting gestures notifications.
Here's another relevant answer: https://stackoverflow.com/a/20712889/2219578
It isn't possible to catch the left, right, top and bottom VoiceOver gestures : I've seen neither a protocol nor a kind of notification for this.
However, you can detect a scrolling action and be aware of the element focus provided by VoiceOver.
Whenever I swipe the page controller and tap the UIPageControl at the bottom in the opposite direction of the swipe at the same time, the page that is currently being displayed and the page number in the pageControl will be out of sync.
Has anyone ever had this weird issue and solved it?
Let me know if you need any additional info.
Just checked out the docs for UIPageControl. I never realized this myself, but you can use page controls for input:
When a user taps a page control to move to the next or previous page,
the control sends the UIControlEventValueChanged event for handling by
the delegate. The delegate can then evaluate the currentPage property
to determine the page to display. The page control advances only one
page in either direction.
My suggestion would be to either disable the page control or update your app to respond to input on it. Setting userInteractionEnabled to false on my page control resolved the problem for me.
I have a relatively simple dialog/popup style UIViewController that isn't behaving correctly. I have many others just like it (though each with a unique button layout) that work just fine. For some reason that I cannot figure out, this controller is only accepting touches within (approximately) the green shaded area.
Note that none of these colors are the actual colors, just placeholders. Same goes for the text.
Tapping in the "Search..." text field does nothing. Tapping on the "Cancel" button does nothing. No UI reaction whatsoever.
The tableview will scroll just fine (there are over 100 rows) if it's touched inside (approximately) the green region. Touching the tableview below the green results in no response. Same thing for the "Cats" button. It reacts when touched in approximately the top half, but nothing in the bottom half.
I've banged my head against the wall for the requisite "several hours" and am getting nowhere.
It seems that part of your view controller's view is overlapped with some "harmful" view/views. Maybe this view is created programmatically and is not visible in IB. You should start with checking your views hierarchy. Put breakpoint in your view controller's code. Somewhere, where you are sure all views (normal and harmful) are already created and type in debug area
po [self.view recursiveDescription]
you should receive something like
Now try to find harmful views. Temporarily delete some "normal" views could be a good idea.
I found my solution. I have a method that launches a dialog controller given the dialog to launch and the parent (up until this point, always a full-screen view controller). The parent gets darkened and the dialog gets launched on the center of the screen.
This one wasn't working because I was launching it from an existing dialog; I was telling the dialog launcher that the new dialog's parent was the current dialog, not the whole screen. This means that the new dialog (which is bigger than the first one) launches at the correct size, but only accepts input inside the area of the "parent" dialog, which is the smaller one underneath it.
Fix: Launch the new dialog using the current dialog's parent (which is full screen) and it works fine. The green zone on my image is the approximate size of the dialog that was being used as the parent, which is why input was only being accepted in that area.
This is one of those "it was working a while ago" troubleshooting efforts.
I'm working on the document preview view controller, in which is a scroll view, which itself contains subclasses of UIView that represent each document. I'm modeling this pretty closely to how Keynote handles its document preview, except I build my scroll view horizontally and with paging. But the standard user experience is present: Long press on a document icon causes all document icons to start jiggling, nab bar has + button and Edit button, etc.
The issue at hand is that when you tap on the name of a document, I hide all the others, move the one being edited front and center, build a new text edit field, add it as a subview atop the real name label, and set it as first responder; but the
[editNameTextField setClearButtonMode:UITextFieldViewModeWhileEditing];
while correctly showing in the edit field is not taking any action when the user taps on the clear button.
I can't figure out what I may have done to cause this to not work -- it had been!
My first thought was that somehow my instance of this subclass is no longer the delegate for this text edit field. To try and confirm/deny that, I usurped a tap on the image view of the document preview to compare the delegate property to self, and it passes.
if (editNameTextField) {
NSLog(#"editNameTextField is still active");
if ([editNameTextField.delegate isEqual:self]) {
NSLog(#"we're still the delegate for the editNameTextField");
}
}
Editing the text within the edit field works fine. Pressing the Return/Done key correctly sends the delegate message textFieldShouldReturn:
While investigating this I implemented the delegate method textFieldShouldClear: just to write a log message if the method gets called (and return YES of course). It never gets called.
My next thought was that perhaps a subview had covered up the area where the clear button sits. So I implemented textFieldShouldBeginEditing: and used the opportunity to bring my the text field to the front. That didn't change anything either. I set a debugger breakpoint there to play a sound when it was called, and it got called, so I know my text edit field is frontmost.
I have only one troubleshooting strategy remaining: Go backwards through snap shots until it starts working again. Before doing that I thought I'd see if any of the more experienced folks out here have any suggestions of what to try next.
Where are you adding the textfield? As a subview of the scrollView? If you added the textfield and it is out of bounds of its parent view it won't receive any touches.
You can try and not call becomeFirstResponder and see if clicking it will show keyboard. Another possible error might be that the parent view of the UITextField has userInteractionEnabled = NO.
Without seeing more code I'm afraid I can not offer more solutions.