I've been trying to scroll UICollectionView with horizontal scroll, to the next page when isPagingEnabled property was set as true. I've been working on it for couple of days and I've made a lot of research, but I couldn't find any case like mine. If you already had this problem and if you already found a solution for it, it would be great sharing your solution way with me. Here is my current case;
func sampleTest() {
let collectionView = app.collectionViews[.sampleCollectionView]
collectionView.waitUntil(.exists)
let totalPageCount = collectionView.cells.count
guard totalPageCount > 0 else {
XCTFail("No pages could find in collection to take snapshot.")
return
}
for currentPage in 1...totalPageCount {
snapshot("Page\(currentPage)")
collectionView.swipeLeft()
}
}
Here, swipeLeft() method of XCUIElement is not working as expected in my case. When I call the method, it is not moving to the next page. It swipes a little bit and turn back due to isPagingEnabled = true statement.
In addition, there is another problem that collectionView.cells.count is calculated wrong. It always returns 1. I assume that the reason of the problem is about reusability. Because the other cells has not dequeued yet. Or collectionView.cells.count is not working as I guess?
I'm using probably a little bit exotic way of initialization of my UI components. I create them programmatically and among them is a UITableView instance, I set its background color immediately upon initialization, like this:
class MyViewController: UIViewController {
...
let tableView = UITableView().tap {
$0.backgroundColor = .black
$0.separatorStyle = .none
}
...
}
where tap is extension function:
func tap(_ block: (Self) -> Void) -> Self {
block(self)
return self
}
This worked very well in my previous project which was created in Xcode 8 and then migrated to Xcode 9 without breaking anything. But now I've created brand new project in Xcode 9 and copy-pasted above-mentioned extension to it, but seems like something went wrong. When my view controller appears on screen table has white background and default separator insets.
This seems to affect only some of the properties because others are working as they should have (e.g. $0.register(nib: UINib?, forCellReuseIdentifier: String) registers required cell class and $0.showsVerticalScrollIndicator = false hides scroll indicator).
Perhaps some of you, guys, could give me an idea what's the heart of the matter.
Here's full code, to reproduce the issue simply create a new project and replace ViewController.swift's content. As you can see, table has correct rowHeight (160) but resets its background color.
As for "before view appears" statement: I've printed table's background color in viewDidLoad, viewWillAppear and viewDidAppear like this:
print(#function, table.backgroundColor.debugDescription)
– it changes its color only in the last debug print:
viewDidLoad() Optional(UIExtendedGrayColorSpace 0 1)
viewWillAppear Optional(UIExtendedGrayColorSpace 0 1)
viewDidAppear Optional(UIExtendedSRGBColorSpace 1 1 1 1)
I ended up moving the initialization to lazy var's function – turns out initializing UITableView during the initialization of it's view controller has some side effects.
It seems like Apple's new feature of auto-flip interface on RTL languages cause problems when using UICollectionView.
I used constraints of type Trailing/Leading for the collection view and they switched their values, as they should, on RTL language.
The problem is that the data actually presented is of the last indexPath in the collection's data source but the UIScrollView.contentOffset.x of the first cell is 0.
A proper behaviour would have been one of the following:
Displaying the first indexPath correctly and switching the direction of the scroll (to the right) - Best option
Not flipping the UI/Constraints so the presented-data / indexPath / scrollView.contentOffset.x will be synchronised - Option that disabling the RTL support.
Presenting cell and data of the last indexPath but fixing the scrollView.contentOffset.x to represent the last cell position also.
I guess Apple might fix it sometime in the future but meanwhile we'll have to use workarounds like reversing array and/or scrolling to the last object.
I was in a similar situation and found a solution for this. If you are using swift, add the following snippet to your project, and it will make sure that the bounds.origin always follows leading edge of the collection view.
extension UICollectionViewFlowLayout {
open override var flipsHorizontallyInOppositeLayoutDirection: Bool {
return true
}
}
If you are using Objective-C, just subclass the UICollectionViewLayout class, and override flipsHorizontallyInOppositeLayoutDirection, and return true. Use this subclass as the layout object of your collection view.
I am late but if you don't want to create an extension because it will affect all the collection View in our app. Simply create your own custom class ie.
class CustomLayoutForLocalization : UICollectionViewFlowLayout{
open override var flipsHorizontallyInOppositeLayoutDirection: Bool {
return true
}
}
To use this class:
// your way of deciding on whether you need to apply this layout may vary depending on use of other tools like LanguageManager_iOS to handle multi-language support
if myCollectionView.effectiveUserInterfaceLayoutDirection == .rightToLeft {
let customLayout = CustomLayoutForRTL()
// if your elements are variable size use the following line
customLayout.estimatedItemSize = UICollectionViewFlowLayout.automaticSize
// if you want horizontal scroll (single line)
customLayout.scrollDirection = .horizontal
myCollectionView.collectionViewLayout = customLayout
}
There is one common solution for that problem that works for me, follow below steps to overcome that problem,
Give the auto layout constraint as per your requirement and then from attribute inspector change the semantic control property of the collection view to Force right-to-left from the storyboard.
Then open storyboard as source code and find for the “leading” attributes of your relevant collection view and replace that with the “left” and same for the “trailing” replace that with the “right”. Now you almost done.
now that will give you result as per your requirement.
import UIKit
extension UICollectionViewFlowLayout {
open override var flipsHorizontallyInOppositeLayoutDirection: Bool {
return UIApplication.shared.userInterfaceLayoutDirection == UIUserInterfaceLayoutDirection.rightToLeft
}
not pretty though simple math does the trick. (for horizontal collectionview)
- (void)switchSemanticDirection:(UISwitch*)sender {
//TEST switch the semantic direction between LTR and RTL.
if (sender.isOn) {
UIView.appearance.semanticContentAttribute = UISemanticContentAttributeForceLeftToRight;
} else {
UIView.appearance.semanticContentAttribute = UISemanticContentAttributeForceRightToLeft;
}
[self.myContent removeFromSuperview];
[self.view addSubview:self.myContent];
//reload your collection view to apply RTL setting programmatically
[self.list reloadData];
//position your content into the right offset after flipped RTL
self.list.contentOffset = CGPointMake(self.list.contentSize.width - self.list.contentOffset.x - self.list.bounds.size.width,
self.list.contentOffset.y);
}
The problem I'm trying to solve is this: I have a DetailViewController that displays the data for my Model with UIImageView's, UITextFields's, etc.
If the user taps a button, those DetailViewController's views move to different positions and start to be editable. When editable, if the user taps one of the UITextField (just one of them is special) the UITextField moves to the top of the screen and a UITableView appears to autocomplete it (just like when you type something on google).
The user can also tap the same button to go back to the display state (where nothing is editable).
So basically I have some views in a ViewController with 3 possible state: DisplayState, EditingState, EditingWithFocusOnSpecialTextFieldsState.
I'd like to have all those positioning state described by NSLayoutConstraints, and, if possible, just in the storyboard.
One thing I could do is this Animate to a storyboard state / position, but this involves writing every constraint for each state in code, therefore I couldn't visualize them really well in storyboard while developing (Also, writing constraints in code is a lot less maintainable than in storyboard).
What I would like is something like creating 3 different XIBs, for example, or different copies of my DetailViewController in storyboard with the 3 different positions for each of the subviews, and then animate between them.
If it makes any difference, I'm always using the latest iOS version (iOS 8 right now) and Swift.
I do know Objective-C very well too if you don't want to answer in Swift.
As far as I know, there's no way to do this with 3 different views, and get the result you want (at least no straight forward way). One approach would be to make 3 constraints (one for each state) to any one edge of the superview that you need to adjust for each view (in addition to any other constraints you need that you're not going to modify). One would have a high priority (I'm using 900, it can't be 1000), and the other 2 would have a lower priority (499 in my example). When you switch states, you change which of the 3 has the high priority. This does involve making a lot of constraints, and I found that the easiest way to implement the switching in code was to give the constraints identifiers in IB (which you do in the "User Defined Runtime Attributes" section of the Identity Inspector). This approach means I don't have to make IBOutlets for all those constraints. Here is an example with two views in the storyboard,
You can see the text field has 3 constraints to the top, and the image view has 3 centerY constraints (though you can't see that there are 3). Each constraint (in the groups of 3) has its identifier set to "display", "edit", or "focus". I give the one that's called "display" the priority of 900, and the other 2 get 499 (because I want the view to start in display mode). In this test app, I'm using 3 buttons to change the state, though, of course, you could use other means to accomplish that. Here is the code I use to switch the priorities,
enum EditState: String {
case Display = "display" // these strings are the same as the ones assigned to the identifier property of the constraints in IB (in "user defined runtime attributes")
case Editing = "edit"
case EditWithFocus = "focus"
}
class ViewController: UIViewController {
#IBOutlet weak var imageView: UIImageView!
func updatEditingState(state: EditState) {
var constraintsArray = self.view.constraints() as [NSLayoutConstraint]
constraintsArray += self.imageView.constraints() as [NSLayoutConstraint]
for con in constraintsArray {
if let name = con.identifier? {
if name == "display" || name == "edit" || name == "focus" {
con.priority = (name == state.rawValue) ? 900 : 499
}
}
}
UIView.animateWithDuration(0.5) {self.view.layoutIfNeeded()}
}
#IBAction func EnterEditingState(sender: UIButton) {
updatEditingState(EditState.Editing)
}
#IBAction func enterDisplayStatus(sender: UIButton) {
updatEditingState(EditState.Display)
}
#IBAction func enterFocusStatus(sender: UIButton) {
updatEditingState(EditState.EditWithFocus)
}
}
We use KIF for our functional testing, and it uses the accessibility label of elements to determine where to send events. I'm currently trying to test the behaviour of a UISegmentedControl, but in order to do so I need to set different accessibility labels for the different segments of the control. How do I set the accessibility label for a particular segment?
As Vertex said,
obj-c
[[[self.segmentOutlet subviews] objectAtIndex:3] setAccessibilityLabel:#"GENERAL_SEGMENT"];
swift
self.segmentOutlet.subviews[3].accessibilityLabel = "GENERAL_SEGMENT"
some advice so you don't go crazy like I did:
To scroll in accessibility mode swipe three fingers
The indexes of the segments are backwards than you would expect, i.e. the furthest segment to the right is the 0th index and the furthest to the left is the n'th index where n is the number of elements in the UISegmentControl
I'm just getting started with KIF myself, so I haven't tested this, but it may be worth a try. I'm sure I'll have the same issue soon, so I'd be interested to hear if it works.
First, UIAccessibility Protocol Reference has a note under accessibilityLabel that says:
"If you supply UIImage objects to display in a UISegmentedControl, you can set this property on each image to ensure that the segments are properly accessible."
So, I'm wondering if you could set the accessibilityLabel on each NSString object as well and be able to use that to access each segment with KIF. As a start, you could try creating a couple of strings, setting their accessibility labels, and using [[UISegmentedControl alloc] initWithItems:myStringArray]; to populate it.
Please update us on your progress. I'd like to hear how this goes
Each segment of UISegmentedControl is UISegment class instance which subclass from UIImageView. You can access those instances by subviews property of UISegmentedControl and try to add accessibility for them programmatically.
You can't rely on the index in the subviewsarray for the position. For customisation of the individual subviews I sort the subviews on their X Position before setting any propery.What would also be valid for accesibilityLbel.
let sortedViews = self.subviews.sorted( by: { $0.frame.origin.x < $1.frame.origin.x } )
sortedViews[0].accessibilityLabel = "segment_full"
sortedViews[1].accessibilityLabel = "segment_not_full"
This is an old question but just in case anyone else runs up against this I found that the segments automatically had an accessibility label specified as their text. So if two options were added of Option 1 and Option 2. A call to
[tester tapViewWithAccessibilityLabel:#"Option 2"];
successfully selected the segment.
The solutions with using an indexed subview is not working since you cannot rely on a correct order and it will be difficult to change the number of segments. And sorting by origin does not work, since the frame (at least for current versions) seems to be always at x: 0.
My solution:
(segmentedControl.accessibilityElement(at: 0) as? UIView)?.accessibilityLabel = "Custom VoiceOver Label 1"
(segmentedControl.accessibilityElement(at: 1) as? UIView)?.accessibilityLabel = "Custom VoiceOver Label 2"
(segmentedControl.accessibilityElement(at: 2) as? UIView)?.accessibilityLabel = "Custom VoiceOver Label 3"
Seems to work for me and has the correct order. You also do not rely on an image. Not that pretty either but maybe more reliable than other solutions.
This is an old question but just in case anyone else runs up against this I found that the segments automatically had an accessibility label specified as their text.
Further to Stuart's answer, I found it really useful when writing test cases to turn on 'Accessibility Inspector' on the Simulator (Settings -> General -> Accessibility -> Accessibility Inspector). You'd be surprised how many elements already have accessibility labels included, like in the standard iOS UI elements or even third party frameworks.
Note: Gestures will now be different - Tap to view accessibility information, double tap to select. Minimizing the Accessibility Inspector window (by tapping the X button) will return the gestures back to normal.
You guys want to see how Apple recommends it be done?
It's FUGLY.
This is from this example:
func configureCustomSegmentsSegmentedControl() {
let imageToAccessibilityLabelMappings = [
"checkmark_icon": NSLocalizedString("Done", comment: ""),
"search_icon": NSLocalizedString("Search", comment: ""),
"tools_icon": NSLocalizedString("Settings", comment: "")
]
// Guarantee that the segments show up in the same order.
var sortedSegmentImageNames = Array(imageToAccessibilityLabelMappings.keys)
sortedSegmentImageNames.sort { lhs, rhs in
return lhs.localizedStandardCompare(rhs) == ComparisonResult.orderedAscending
}
for (idx, segmentImageName) in sortedSegmentImageNames.enumerated() {
let image = UIImage(named: segmentImageName)!
image.accessibilityLabel = imageToAccessibilityLabelMappings[segmentImageName]
customSegmentsSegmentedControl.setImage(image, forSegmentAt: idx)
}
customSegmentsSegmentedControl.selectedSegmentIndex = 0
customSegmentsSegmentedControl.addTarget(self,
action: #selector(SegmentedControlViewController.selectedSegmentDidChange(_:)),
for: .valueChanged)
}
They apply the accessibility labels to images, and then attach the images. Not too different from the above answer.
another option if not willing to set accesibility label might be calculating the poistion of each segment part and use
[tester tapScreenAtPoint:segementPosition];
to trigger the actions
If you look at the segmented control thru the accessibility inspector, you find that the segments are UISegment objects. Moreover, they turn out to be direct subviews of the UISegmentedControl. That fact suggests the following insanely crazy but perfectly safe Swift 4 code to set the accessibility labels of the segments of a UISegmentedControl:
let seg = // the UISegmentedControl
if let segclass = NSClassFromString("UISegment") {
let segments = seg.subviews.filter {type(of:$0) == segclass}
.sorted {$0.frame.minX < $1.frame.minX}
let labels = ["Previous article", "Next article"] // or whatever
for pair in zip(segments,labels) {
pair.0.accessibilityLabel = pair.1
}
}
As mentioned in the accepted answer, adding accessibilityLabel to the text should do the trick:
let title0 = "Button1" as NSString
title0.accessibilityLabel = "MyButtonIdentifier1"
segmentedControl.setTitle("\(title0)", forSegmentAt: 0)
let title1 ="Button2" as NSString
title1.accessibilityLabel = "MyButtonIdentifier2"
segmentedControl.setTitle("\(title1)", forSegmentAt: 1)
XCode 12 / iOS 14.3 / Swift 5
This is an old post but I encountered the same problem trying to set accessibility hints for individual segments in a UISegmentedControl. I also had problems with some of the older solutions. The code that's currently working for my app borrows from replies such as those from matt and Ilker Baltaci and then mixes in my own hack using UIView.description.
First, some comments:
For my UISegmentedControl with 3 segments, the subview count is 3 in the viewDidLoad() and viewWillAppear() of the parent UIVIewController. But the subview count is 7 in viewDidAppear().
In viewDidLoad() or viewWillAppear() the subview frames aren't set, so ordering the subviews didn't work for me. Apparently Benjamin B encountered the same problem with frame origins.
In viewDidAppear(), the 7 subviews include 4 views of type UIImageView and 3 views of type UISegment.
UISegment is a private type. Working directly with the private API might flag your app for rejection. (see comment below)
type(of:) didn't yield anything useful for the UISegment subviews
(HACK!) UIView.description can be used to check the type without accessing the private API.
Setting accessibility hints based on X order tightly couples UI segment titles and hints to their current positions. If user testing suggests a change in segment order, then changes must be made both in the UI and in the code to set accessibility hints. It's easy to miss that.
Using an enum to set segment titles is an alternative to relying on X ordering set manually in the UI. If your enum inherits from String and adopts the protocols CaseIterable and RawRepresentable, then it's straightforward to create titles from the enum cases, and to determine the enum case from a segment title.
There's no guarantee the following will work in a future release of the framework, given the reliance on description.contains("UISegment") but it's working for me. Gotta move on.
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
// get only the UISegment items; ignore UIImageView
let segments = mySegmentedControl.subviews.compactMap(
{ $0.description.contains("UISegment") ? $0 : nil }
)
let sortedSegments = segments.sorted(
by: { $0.frame.origin.x < $1.frame.origin.x }
)
for i in 0 ..< sortedSegments.count {
let segment = sortedSegments[i]
// set .accessibilityHint or .accessibilityLabel by index
// or check for a segment title matching an enum case
// ...
}
}
On Private APIs and Rejection
I'm referring to the April 2016 comment from #dan in Test if object is an instance of class UISegment:
It's a private class. You can check it with [...
isKindOfClass:NSClassFromString(#"UISegment")] but that may get your
app rejected for using private api or stop working in the future if
apple changes the internal class name or structure.
Also:
What exactly is a Private API, and why will Apple reject an iOS App if one is used?
"App rejected due to non-public api's": https://discussions.apple.com/thread/3838251
As Vortex said, the array is right to left with [0] starting on the right. You can set every single accessibility option by accessing the subviews. Since the subviews are optional, it is good to pull out the subview first, and then assign the accessibility traits that you want. Swift 4 example for a simple two option segment control:
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
guard let rightSegment = segmentControl.subviews.first, let leftSegment = segmentControl.subviews.last else { return }
rightSegment.accessibilityLabel = "A label for the right segment."
rightSegment.accessibilityHint = "A hint for the right segment."
leftSegment.accessibilityLabel = "A label for the left segment."
leftSegment.accessibilityHint = "A hint for the left segment."
}