I've created a custom view that acts like a UISlider - there is a "track", and a handle to "grab" to change the value. For particular reasons, I can't just make it a subclass of UISlider. I'm trying to make this slider as accessible as possible with VoiceOver. I have accessibilityIncrease and accessibilityDecrease on my custom view that handle single finger drag up and single finger drag down. This changes the value of the slider by 10% at a time.
However, I'd like to allow more fine grained control, just like a non-VoiceOver slider. By default , UISlider has double tap and hold, and you can drag up/down to "pan" the slider. I'd like to add exactly that to my custom view, but I can't find the correct incantation to handle the double tap and hold gesture.
Is there something I can do to mimic the double tap and hold gesture from UISlider on my custom view?
Thanks very much!!!
If you want to implement this kind of new gesture for VoiceOver users, just forget it.
The recommended gesture for this kind of UI control is definitely the implementation of adjustable value as you already did apparently.
I don't think it's a good idea to try and implement new VoiceOver gestures in an application because its users have their habits and they may be totally lost with your customed control if they cannot handle it unless you add an hint to explain but that's definitely not what I recommend anyway.
Otherwise, you could take a look at the pass through concept introduced in the What's New in Accessibility WWDC 2017 video that deals with the same idea but for a panning gesture...
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I am making app like sudoku (9*9 boxes) but it has only binary choices (on/off) and using button gave me horrible results. Can anyone give me demo version of 9*9 (or 3*3) box where depending upon the tap location, that specific box gets toggled (on/off)
You could create a custom subclass of UIView that had an attached tap gesture recognizer and interpreted the tap location to figure out which cell is being tapped, but it would be a lot of work.
It would be better to have custom view that contains a grid of buttons and set up the button actions to do what you want.
You said "...using button gave me horrible results." Can you elaborate? That should be a good way to go, so any "horrible results" are likely the result of something you did wrong, rather than that being the wrong way to go.
I'm working on an app with a musical keyboard component.
I need 2 types of "sent events" to trigger the keys of the keyboard (UIButtons).
1) "Touch Down" triggers the buttons they way I need it to
2) The 2nd way I need buttons to be triggered is by sliding onto a button,from another button/key to the side of it as if it is "touched down" upon, when it is slid upon from the left or right.
How do I achieve this?
You can't do this using the built-in control events of the buttons, for the simple reason that you don't get an event in a button at all unless the touch is initially in that button (as I explain here: https://stackoverflow.com/a/40414929/341994).
Still, this doesn't sound very hard to do. The simplest approach is probably to put the touch response (such as a gesture recognizer) into the common superview of all the buttons. The superview can then track the gesture. And it can very easily find out which button the touch is currently inside at any given moment. So it can manage the whole interaction. It can even send messages to the buttons telling them when to highlight and unhighlight. (And if you aren't going to use the button touch handling for anything, you might even want to give up the idea that these are buttons; they could just be views or custom controls that look like buttons.)
Brent Simmons wrote in a blog post that tap gesture recognizers, presumably on a UIView, are less accessible than UIButtons. I'm trying to learn my way around making my app accessible, and I was curious if anyone could clarify what makes that less accessible than a UIButton, and what makes an element "accessible" to begin with?
For more customizability I was planning to build a button comprised of a UIView and tap gesture recognizers with some subviews, but now I'm not so sure. Is it possible to make a UIView as accessible as a UIButton?
Accessible in this context most likely refers to UI elements that can be used using Apple's accessibility features, such as VoiceOver (see example below).
For example, a visually impaired person will not be able to see your view or subviews, or buttons for that matter; but the accessibility software "VoiceOver" built into every iOS device will read to her/him the kind of object and its title, something like "Button: Continue" (if the button title is "Continue").
You can see that most likely the tap gesture recognizer will not be read by VoiceOver and thus be less "accessible".
I know this has been probably asked before but I've seen many approaches and i don't know which is best for me, so plz don't send me a link to another post unless it addresses my problem directly.
I have a controller which has a uiview on the top (like a header) (this header is bigger than it seems because is partially hidden on top). on that view i have a uibutton which now with a touch up inside shows the entire header view and taping again returns it to its starting position (changing frame with animation). I want to also be able to drag the view but only changing position on the y axis(dragging up and down)... i was thinking of adding the dragInside/Outside event to the button but this doesn't give me the position of the finger... and also want to know when the user releases the drag so the view ends animation to any of its two possible states (showing or partially hidden). Is this a "touches began" , "touches moved" , "touches ended" thing? if it is please provide a code example. I also want to do this with another view but this is on the left side... same thing but this one moves on the X axis... any help is appreciated. or maybe it can be made with drag event if i only can save a CGpoint of last touch, maybe that's better, any other suggestions
Look at using a UIPanGestureRecognizer to detect the touch movements. Use the translationInView: of the gesture to set the view y position. The translation is the total movement since the start of the gesture so you don't need to remember and accumulate the offset position yourself.
The main thing to worry about while implementing this is bounding the y position of the view so that no matter how far the user drags the view won't go too high or low on the screen.
Use a UIPanGestureRecognizer, that's a class dedicated to handling such drag/pan gestures.
Everything is described here in Apple's documentation, including examples, so you should find your answer here.
There is also some sample code in Apple Developer Library that shows you how to use Gesture Recognizers if needed.
i am trying to implement accessibility option in my book reader app. I have a slider(similar to ibooks) which is used for navigating between pages. i have seen this question posted by another user and implemented the same code in my app. Right now my slider is responding when i'm tapping on it. The voiceover is also speaking the label i have given in the code. But, the problem is that, i am unable to change the slider value and navigate to another page.. I dont know if it is the problem with my code or is it that i do not know how to replicate the gesture to change the value of the slider... Any help in this regard will be appreciated.... Thanku
Does the slider work with VoiceOver turned off?
If so, try swiping vertically up or down (top to bottom of display) after selecting the slider element with VoiceOver enabled.
Is it a UISlider, or something of your own devising? UISlider needs an actual vertical swipe once selected, and moves a pretty significant amount as a result — not a good experience for going to the next page.
If it's your own custom control, be sure you set UIAccessibilityTraitAdjustable.