UISheetPresentationController and UndimmedDetentIdentifier with custom Detent - ios

How can I use LargestUndimmedDetentIdentifier with custom SheetPresentation height ?
I have a UISheetPresentationController with two customs Detents and I don't find how can interact with content underneath.
UISheetPresentationController sheet = NavigationController!.SheetPresentationController!;
sheet.PrefersGrabberVisible = true;
sheet.PrefersScrollingExpandsWhenScrolledToEdge = false;
sheet.WidthFollowsPreferredContentSizeWhenEdgeAttached = true;
sheet.Delegate = new SheetPresentationControllerDelegate();
UISheetPresentationControllerDetent smallDetent = UISheetPresentationControllerDetent.Create("small", _ => 60);
UISheetPresentationControllerDetent msmallPlusDetent = UISheetPresentationControllerDetent.Create("smallPlus", _ => 350);
sheet.Detents = new UISheetPresentationControllerDetent[]
{
smallDetent,
msmallPlusDetent
};
sheet.LargestUndimmedDetentIdentifier = ????; (what can I put here?)

Your custom detents height is an object that represents a height where a sheet naturally rests. The LargeUndimmedDetentIdentifier property needs to be an enumeration of UISheetPresentationControllerDetentIdentifier. Its function is that it doesn't dim the view underneath the sheet. At present, iOS only defines two enumeration types, Medium and Large, and there is no way to customize changes for the time being.
You can only use these two ways:sheet.LargestUndimmedDetentIdentifier=UISheetPresentationControllerDetentIdentifier.Medium/Large
For more details, you can refer to:
largestUndimmedDetentIdentifier | AppleDeveloper
UISheetPresentationControllerDetentIdentifier | AppleDeveloper

Related

How to make ClickableText accessible to screen readers

This code creates a ClickableText element in Jetpack Compose Composable:
ClickableText(
text = forgotPasswordAnnotatedString,
onClick = {
context.startActivity(intent)
},
modifier = Modifier
.padding(top = mediumPadding)
)
The annotated string is defined here to make the text look like a link:
val forgotPasswordAnnotatedString = buildAnnotatedString {
append(stringResource(R.string.forgot_password))
addStyle(
style = SpanStyle(
textDecoration = TextDecoration.Underline,
color = Color.White,
fontSize = 16.sp,
fontWeight = FontWeight.Medium
),
start = 0,
end = 21,
)
}
When I encounter this text using the TalkBalk screen reader in Android, the screenreader does not make it clear that this is clickable text that will do something which tapped on. The reader just reads the text.
Is there a way to make it clear to the screen reader that this text is interactive? Otherwise should I just use a button and style it to look like a link?
It looks like your intention is for the whole text to be clickable? In which you best option is probably a TextButton as suggested by
Gabriele Mariotti.
But if you wan't only part of the link to be clickable, or to have multiple clickable sections, the best I've been able to land on is to draw an invisible box overtop of the Text. It means that I can control the touch target of the clickable area to be at least 48.dp and can use the semantics{} modifier to control how a screen reader interprets it.
Would welcome any suggestions.
// remember variables to hold the start and end position of the clickable text
val startX = remember { mutableStateOf(0f) }
val endX = remember { mutableStateOf(0f) }
// convert to Dp and work out width of button
val buttonPaddingX = with(LocalDensity.current) { startX.value.toDp() }
val buttonWidth = with(LocalDensity.current) { (endX.value - startX.value).toDp() }
Text(
text = forgotPasswordAnnotatedString,
onTextLayout = {
startX.value = it.getBoundingBox(0).left // where 0 is the start index of the range you want to be clickable
endX.value = it.getBoundingBox(21 - 1).right // where 21 is the end index of the range you want to be clickable
}
)
Note that buttonPaddingX is relative to the Text position not the Window, so you may have to surround both in a Box{} or use ConstraintLayout.
Then to draw the invisible box
Box(modifier = Modifier
.sizeIn(minWidth = 48.dp, minHeight = 48.dp) // minimum touch target size
.padding(start = buttonPaddingX)
.width(buttonWidth)
// .background(Color.Magenta.copy(alpha = 0.5f)) // uncomment this to debug where the box is drawn
.clickable(onClick = { context.startActivity(intent) })
.semantics {
// tell TalkBack whatever you need to here
role = Role.Button
contentDescription = "Insert button description here"
}
)
In my code I'm using pushStringAnnotation(TAG, annotation) rather than reference string indexes directly. That way I can get the start and end index of the clickable area with annotatedString.getStringAnnotations(TAG,0,annotatedString.length).first(). Useful if there a multiple links within the text.
It's disappointing that ClickableText doesn't have accessibility in mind from the get go, hopefully we'll be able to use it again in a future update.
Adding .semantics.contentDescription to the Modifier changes what is read by the screen reader. I had to word contentDescription to make it clear that this was a link to reset the your password.
The screen reader still doesn't recognize the element a clickable but hopefully the description will be useful to convey to the user that this element is interactive.
ClickableText(
text = forgotPasswordAnnotatedString,
onClick = {
context.startActivity(intent)
},
modifier = Modifier
.padding(top = mediumPadding)
// new code here:
.semantics {
contentDescription = "Forgot your password? link"
}
)

Jetpack Compose - Row Clipping Children When Width Increases

Here on the right , I have a list of items in a composable , Every item is inside a row , All the items are inside a column
All the children of the are getting clipped to fit the screen which I don't want , I want these items to render completely even if outside of screen since I have a zoomable container above them
As you can see how text in the text field is all in one line vertically rather than expanding the width , This is the problem
Code :
Row(
modifier = modifier.zIndex(3f),
verticalAlignment = Alignment.CenterVertically,
horizontalArrangement = Arrangement.Center,
) {
SimpleNodesList(
modifier = Modifier.padding(8.dp),
parentNode = state.center,
nodes = state.center.left,
renderRight = false,
)
SimpleNode(node = state.center, parentNode = null)
SimpleNodesList(
modifier = Modifier.padding(8.dp),
parentNode = state.center,
nodes = state.center.right,
renderLeft = false
)
}
Simple Nodes List is a column of rows , I have one column on left and one on the right , If the width of the left column increases , right row get's clipped by the screen
Using this modifier does the job for the row , In my case I also needed this layout modifier , wrapContentSize(unbounded = true) was working but children weren't clickable for some reason outside the bounds of the zoom container !
I also had to create a modifier zoomable rather than use a zoomable box , so the zoomable touch events would be dispatched on the this composable rather than the parent !
modifier = Modifier
.layout { measurable, constraints ->
val r =
measurable.measure(constraints = constraints.copy(maxWidth = Constraints.Infinity))
layout(r.measuredWidth, r.measuredHeight, placementBlock = {
r.placeWithLayer(0, 0, 0f) {
}
})
}
.wrapContentSize(unbounded = true)
If you are using hard-coded width for the text, applying Modifier.wrapContentSize() on every container might do the job
Use SimpleFlowRow in place of Row. It will fix the clipping issue.

How to render a UIButton in Xamarin.iOS

How do I render a UIButton in Xamarin.iOS? See the current Code for the full list.
This is the code I'm using to create and add the button to the Xamarin.Forms.Platform.iOS.CellTableViewCell cell. I cannot get the button to display anything.
With the use of a Foundation.NSMutableAttributedString, it shows a cut-off section of text in the top left corner, regardless of anything I try (alignments, insets, bounds, various constraints, etc). I'm currently trying things from Xamarin.Forms.Platform.iOS.Renderers.ButtonRenderer, but still can't get anything to display at all, no text, no button, or its outline.
If you could fork the repo and fix it or post the solution here, I would be very grateful.
protected override void SetUpContentView()
{
var insets = new UIEdgeInsets(SVConstants.Cell.PADDING.Top.ToNFloat(), SVConstants.Cell.PADDING.Left.ToNFloat(), SVConstants.Cell.PADDING.Bottom.ToNFloat(), SVConstants.Cell.PADDING.Right.ToNFloat());
_Button = new UIButton(UIButtonType.RoundedRect)
{
AutoresizingMask = UIViewAutoresizing.All,
HorizontalAlignment = UIControlContentHorizontalAlignment.Center,
VerticalAlignment = UIControlContentVerticalAlignment.Center,
ContentEdgeInsets = insets,
// TitleEdgeInsets = insets
};
DefaultFontSize = _Button.TitleLabel.ContentScaleFactor;
DefaultTextColor = _Button.TitleLabel.TextColor;
_Recognizer = new UILongPressGestureRecognizer(RunLong);
_Button.TouchUpInside += OnClick; // https://stackoverflow.com/a/51593238/9530917
_Button.AddGestureRecognizer(_Recognizer); // https://stackoverflow.com/a/6179591/9530917
ContentView.AddSubview(_Button);
_Button.CenterXAnchor.ConstraintEqualTo(ContentView.CenterXAnchor).Active = true;
_Button.CenterYAnchor.ConstraintEqualTo(ContentView.CenterYAnchor).Active = true;
_Button.WidthAnchor.ConstraintEqualTo(ContentView.WidthAnchor).Active = true;
_Button.HeightAnchor.ConstraintEqualTo(ContentView.HeightAnchor).Active = true;
UpdateConstraintsIfNeeded();
LayoutIfNeeded();
}
Found out that you can't subclass it. Any button added to the view must be native (UIButton) or custom rendered, such as Xamarin.Forms.Platform.iOS.ButtonRenderer; It doesn't show up otherwise.

Wrapping text on TitleLabel and DetailLabel - Material Card

I am using CosmicMind - Material Framework to create a Card. titleLabel and DetailLabel do not wrap to a new line.
My question is: What do I need to do to accomplish such task and is it supposed to be automatically adjusted by the framework?
This is what I have so far:
let card = Card()
var heartIcon = IconButton()
heartIcon = IconButton(image: Icon.favoriteBorder, tintColor: Color.red.base)
//Title Bar
let toolbar = Toolbar(rightViews: [heartIcon])
toolbar.title = cardData.cardTitleText
toolbar.titleLabel.textAlignment = .left
toolbar.titleLabel.numberOfLines = 0
toolbar.detail = "Company: " + cardData.cardTitleSubtitle
toolbar.detailLabel.font = RobotoFont.regular(with: 14)
toolbar.detailLabel.textColor = Color.grey.base
toolbar.detailLabel.textAlignment = .left
toolbar.detailLabel.numberOfLines = 0
And this is my output:
Update:
I managed to achieve what I wanted by increasing the size of the toolbar frame.
toolbar.frame = CGRect(x:0,y:0,width: view.frame.width,height: 100)
My goal was to at least show 2 lines of text.
Thanks!
I have no experience with the CosmicMind framework but usually, the label.numberOfLines property defines the maximum number of lines that the label text can have. You can set it to 2 instead of 0 and it should wrap.

Why isn't cell resizing when content is taller than the EstimatedSize (sizeHint)

I ported a table view implementation from Swift with a variable height cell. But in my Xamarin/ReactiveUI implementation, the cell does not resize when the content grows (i.e. when an optional label is displayed). Please note that the cell does resize to fit in the native Swift implementation.
Most answers online focus on the setting of two properties on UITableView: RowHeight and EstimatedHeight as well as using AutoLayout. My row height is set to UITableView.AutomaticDimension and the EstimatedHeight is set to 44f. I am using autolayout constraints which I will show below. I am using the BindTo extensions in ReactiveTableViewSourceExtensions.
I also tried setting the Text property of the optional label right away to test the theory that setting the property up front would provoke a resize.
Here are the pertinent lines of code:
In a ReactiveViewController<T> ctor:
this.WhenActivated(disposables =>
{
//// ...
// This method automatically wires up the cell reuse key to be the nameof my cell class which is what I want.
this.WhenAnyValue(view => view._cells)
.BindTo<IImportedFileViewModel, ImportedFileCell>(TableView, 44f)
.DisposeWith(disposables);
//// ...
});
Below in ViewDidLoad:
//// ...
TableView = new UITableView
{
RowHeight = UITableView.AutomaticDimension,
EstimatedRowHeight = 44f, // Setting or not setting this doesn't matter
SeparatorStyle = UITableViewCellSeparatorStyle.None,
AllowsSelection = false,
TranslatesAutoresizingMaskIntoConstraints = false,
};
//// ...
In the cell implementation:
ClipsToBounds = true;
PreservesSuperviewLayoutMargins = true;
ContentView.ClipsToBounds = true;
ContentView.PreservesSuperviewLayoutMargins = true;
var stackView = new UIStackView
{
TranslatesAutoresizingMaskIntoConstraints = false,
Axis = UILayoutConstraintAxis.Vertical,
Distribution = UIStackViewDistribution.Fill,
Alignment = UIStackViewAlignment.Fill,
Spacing = 4,
};
var fileStackView = new UIStackView
{
TranslatesAutoresizingMaskIntoConstraints = false,
Axis = UILayoutConstraintAxis.Horizontal,
Distribution = UIStackViewDistribution.Fill,
Alignment = UIStackViewAlignment.Top,
};
FilenameLabel = new UILabel
{
TranslatesAutoresizingMaskIntoConstraints = false,
Font = UIFont.SystemFontOfSize(15f, UIFontWeight.Medium),
};
fileStackView.AddArrangedSubview(FilenameLabel);
StatusImage = new UIImageView()
{
TranslatesAutoresizingMaskIntoConstraints = false,
ContentMode = UIViewContentMode.Center,
};
fileStackView.AddArrangedSubview(StatusImage);
stackView.AddArrangedSubview(fileStackView);
var reasonStackView = new UIStackView
{
TranslatesAutoresizingMaskIntoConstraints = false,
Axis = UILayoutConstraintAxis.Horizontal,
Distribution = UIStackViewDistribution.Fill,
Alignment = UIStackViewAlignment.Top,
};
// This is the optional label that, when its Text property is set, should resize the cell.
FailureReasonLabel = new UILabel
{
TranslatesAutoresizingMaskIntoConstraints = false,
Font = UIFont.SystemFontOfSize(13f, UIFontWeight.Medium),
Lines = 0,
};
reasonStackView.AddArrangedSubview(FailureReasonLabel);
stackView.AddArrangedSubview(reasonStackView);
ContentView.AddSubview(stackView);
stackView.BottomAnchor.ConstraintEqualTo(ContentView.LayoutMarginsGuide.BottomAnchor).Active = true;
stackView.TopAnchor.ConstraintEqualTo(ContentView.LayoutMarginsGuide.TopAnchor).Active = true;
stackView.LeadingAnchor.ConstraintEqualTo(ContentView.LayoutMarginsGuide.LeadingAnchor).Active = true;
stackView.TrailingAnchor.ConstraintEqualTo(ContentView.LayoutMarginsGuide.TrailingAnchor).Active = true;
StatusImage.HeightAnchor.ConstraintEqualTo(16f).Active = true;
StatusImage.WidthAnchor.ConstraintEqualTo(16f).Active = true;
I would be happy to get a solution to the problem using the basic structure I have now but I would also accept an example of some other pattern that someone has used (based on ReactiveUI) to get this working. I would prefer that the solution not be based on old manual resizing patterns like in the pre-iOS 8 days or some sort of hack.
So two things had to be adjusted to fix my issue.
The sizeHint parameter in the ReactiveUI BindTo method does not behave like TableView.EstimatedRowHeight, which is what I was assuming. So I ended up setting it to the auto dimension constant like this:
.BindTo<IImportedFileViewModel, ImportedFileCell>(TableView, (float)UITableView.AutomaticDimension)
I was thinking that I could just update the properties of the view models within the IObservableCollection implementation that is passed in to the BindTo method but it wasn't until I started provoking changed events on the collection itself (the collection that the view is bound to) that the cells started resizing themselves. So since I am using DynamicData as part of ReactiveUI, that meant calling SourceCache.AddOrUpdate(updatedViewModel) whenever I knew that the FailureReasonLabel had been set.
I am also going to try and restore the ReactiveUI tag that was removed from this post because I believe it to be a relevant part of this question and its answer.

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