The Apple documentation gives some user interface design tips on modal sheets including renaming Cancel to something like Dismiss where relevant. But there's no guide whether this is possible in SwiftUI.
There's a link that takes you to setTitle for Watchkit: https://developer.apple.com/documentation/watchkit/wkinterfacecontroller/1619570-settitle
But is there something equivalent for a SwiftUI Watch app?
Adding a ToolbarItem with the .cancellationAction placement works:
struct MySheet: View {
#Environment(\.dismiss) private var dismiss
var body: some View {
Text("The Content Of Sheet")
.toolbar {
ToolbarItem(placement: .cancellationAction) {
Button("Custom") {
dismiss()
}
}
}
}
}
The result looks like this:
Related
I'm learning SwiftUI and having trouble with closing Each Tab View Element.
My App shows photos from user's album by TabView with pageViewStyle one by one.
And What I want to make is user can click save button in each view, and when button is clicked, save that photo and close only that view while other photos are still displayed. So unless all photos are saved or discarded, if user clicks save button, TabView should automatically move to another one.
However, I don't know how to close only one Tab Element. I've tried to use dismiss() and dynamically changing vm.images element. Latter one actually works, but it displays awkward movement and it also requires quite messy code. How could I solve this issue?
Here is my code.
TabView {
ForEach(vm.images, id: \.self) { image in
TestView(image: image)
}
}
.tabViewStyle(.page(indexDisplayMode: .never))
struct TestView: View {
#ObservedObject var vm: TestviewModel
...
var body: some View {
VStack(spacing: 10) {
Image(...)
Spacer()
Button {
...
} label: {
Text("Save")
}
}
You need actually to remove saved image from the viewModel container, and UI will be updated automatically
literally
Button {
vm.images.removeAll { $0.id == image.id } // << here !!
} label: {
Text("Save")
}
You need to use the selection initializer of TabView in order to control what it displays. So replace TabView with:
TabView(selection: $selection)
Than add a new property: #State var selection: YourIdType = someDefaultValue, and in the Button action you set selection to whatever you want to display.
Also add .tag(TheIdTheViewWillUse) remember that whatever Id you use must be the same as your selection variable. I recommend you use Int for the simple use.
Is there anyway to keep the tab bar showing while presenting a modal / sheet view?
Here is a minimal failing example.
import SwiftUI
struct SheetView: View {
#Environment(\.dismiss) var dismiss
var body: some View {
Button("Press to dismiss") {
dismiss()
}
.padding()
}
}
struct Tab1: View {
#State private var showingSheet = false
var body: some View {
Button("Show Sheet") {
showingSheet.toggle()
}
.sheet(isPresented: $showingSheet) {
SheetView()
}
}
}
struct MainView: View {
var body: some View {
TabView {
Tab1()
.tabItem {
Label("Tab 1", systemImage: "heart")
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
MainView()
}
}
Thanks for answering my question in the comments.
Unfortunately the standard means of presenting views in SwiftUI is that they are truly modal – they capture the whole interaction context for the current scene, and you can’t interact with anything else until the modal is dismissed.
This is also the case for iPadOS. Even though a modal presented with .sheet on an iPad allows much more of the underlying view to be visible, you can’t interact with it until the sheet disappears. You can interact with different parts of the app by running two scenes side-by-side in split screen mode, but each half is a separate scene and any presented sheets are modal for that scene.
If you want one tab to optionally present a view over its usual content but still allow access to the tab view and its other tabs, that’s not a modal context and SwiftUI’s built-in sheet won’t work. You will have to implement something yourself - but I think that’s doable.
Rather than using .sheet, you could optionally add an overlay to your Tab1 view, using the same boolean state variable showingSheet. In this approach, the default dismiss environment variable won’t be available, so passing in the state variable as a binding value would be an alternative:
var body: some View
<main display>
.overlay(showingSheet ? Sheet1(presented: $showingSheet) : EmptyView())
You might also find that a ZStack works better than .overlay depending on what the contents of the tab view actually are.
You’ll definitely have a lot more structural work to do to make this work, but I hope you can see that it’s possible.
I have a SwiftUI app which uses a custom navigation bar. Because of that, I need to handle the back navigation separately (both the back button and the swipe gesture). Everything went fine up until now, when I need to use a TabView to swipe between pages. The code below illustrates what I'm trying to achieve:
ContentView.swift
import SwiftUI
struct ContentView: View {
var body: some View {
NavigationView {
NavigationLink(destination: SecondView()) {
Text("Go to second view")
}
}
}
}
SecondView.swift
import SwiftUI
// Being able to go back by swiping
// https://stackoverflow.com/questions/59921239/hide-navigation-bar-without-losing-swipe-back-gesture-in-swiftui
extension UINavigationController: UIGestureRecognizerDelegate {
override open func viewDidLoad() {
super.viewDidLoad()
interactivePopGestureRecognizer?.delegate = self
}
public func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
return viewControllers.count > 1
}
}
struct SecondView: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack(alignment: .leading) {
Image(systemName: "chevron.left")
.foregroundColor(Color(.systemBlue))
.font(.title2)
.onTapGesture {
self.presentationMode.wrappedValue.dismiss()
}
.padding()
TabView {
Text("Test 1")
.tag(1)
Text("Test 2")
.tag(1)
Text("Test 3")
.tag(3)
}
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .never))
}
.background(Color(.systemGray6))
.navigationBarHidden(true)
}
}
Note that I didn't add the custom navigation bar for the second view, I've just hidden the default navigation bar, as the custom bar is not needed to solve this problem.
When the user is inside the SecondView and presses the back button, everything works as expected. The problem appears when he tries to swipe back, as the swipe back gesture is captured by the TabView. I want to keep the 'swipe-between-pages' functionality of the TabView while being able to go back to ContentView when the user swipes right from the leftmost part of the screen.
This problem only appears when using TabViews, other types of content handle the swipe back gesture without problems.
To solve this problem, I could add a horizontal padding to the TabView like this:
TabView {
// content
}
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .never))
.padding(.horizontal)
and then the user would have some space to swipe back, but this solution is not so good when some views inside the TabView need to take the whole width of the screen.
Is there any way to handle the swipe back gesture in this particular case? Maybe another possible solution would be customizing the TabView to ignore the drag gesture when the first view is presented and a swipe right gesture is captured (I don't know how to implement that).
I ran into this same problem. I solved it by wrapping my first tabview in with a geometryReader. When the bounds of that view is more than a quarter off the screen, I dismiss the view.
enter image description hereI am new to SwiftUI. When I embed a toggle switch inside Vstack, it says "generic param Label cannot be inferred" in SwiftUI. May I know the cause for this error and how to fix it.Thank you
Looks like you might have missed specifying the label or have an error there. I have created the below code that has a toggle button inside VStack.
import SwiftUI
struct ContentView: View {
#State private var isOn: Bool = false
var body: some View {
VStack (alignment: .leading, spacing: 10){
Toggle(isOn: $isOn){
Text("Toggle me to set values")
}
Text("Toggle Value: \(isOn.description)")
Spacer()
}.padding()
}
}
Let me know if this helps.
Toggle Screenshot
I have embedded a text, Two toggles and stepper and a button in Vstack and here I have missed to provide action to that button, which resulted in the issue "generic param Label cannot be inferred".previous Code with issue. After adding the button action
I am creating an App where the login / register part is inside a modal, which is shown if the user is not logged in.
The problem is, that the user can dismiss the modal by swiping it down...
Is it possible to prevent this?
var body: some View {
TabView(selection: $selection) {
App()
}.sheet(isPresented: self.$showSheet) { // This needs to be non-dismissible
LoginRegister()
}
}
Second example:
I am using a modal to ask for information. The user should not be able to quit this process except by dismissing the modal with save button. The user has to input information before the button works. Unfortunately the modal can be dismissed by swiping it down.
Is it possible to prevent this?
iOS 15 and later:
Use .interactiveDismissDisabled(true) on the sheet, that's all.
Prev iOS 15:
You can try to do this by using a highPriorityGesture. Of course the blue Rectangle is only for demonstration but you would have to use a view which is covering the whole screen.
struct ModalViewNoClose : View {
#Environment(\.presentationMode) var presentationMode
let gesture = DragGesture()
var body: some View {
Rectangle()
.fill(Color.blue)
.frame(width: 300, height: 600)
.highPriorityGesture(gesture)
.overlay(
VStack{
Button("Close") {
self.presentationMode.value.dismiss()
}.accentColor(.white)
Text("Modal")
.highPriorityGesture(gesture)
TextField("as", text: .constant("sdf"))
.highPriorityGesture(gesture)
} .highPriorityGesture(gesture)
)
.border(Color.green)
}
}
This is a common problem and a "code smell"... well not really code but a "design pattern smell" anyway.
The problem is that you are making your login process part of the rest of the app.
Instead of presenting the LoginRegister over the App you should really be showing either App or LoginRegister.
i.e. you should have some state object like userLoggedIn: Bool or something and depending on that value you should show either App or LoginRegister.
Just don't have both in the view hierarchy at the same time. That way your user won't be able to dismiss the view.
If you dont mind using Introspect:
import Introspect
#available(iOS 13, *)
extension View {
/// A Boolean value indicating whether the view controller enforces a modal behavior.
///
/// The default value of this property is `false`. When you set it to `true`, UIKit ignores events
/// outside the view controller's bounds and prevents the interactive dismissal of the
/// view controller while it is onscreen.
public func isModalInPresentation(_ value: Bool) -> some View {
introspectViewController {
$0.isModalInPresentation = value
}
}
}
Usage:
.sheet {
VStack {
...
}.isModalInPresentation(true)
}
iOS 15+
Starting from iOS 15 you can use interactiveDismissDisabled.
You just need to attach it to the sheet:
var body: some View {
TabView(selection: $selection) {
App()
}.sheet(isPresented: self.$showSheet) {
LoginRegister()
.interactiveDismissDisabled(true)
}
}
Regarding your second example, you can pass a variable to control when the sheet is disabled:
.interactiveDismissDisabled(!isAllInformationProvided)
You can find more information in the documentation.
theoretically this may help you (I didn't tryed it)
private var isDisplayedBind: Binding<Bool>{ Binding(get: { true }, set: { _ = $0 }) }
and usage:
content
.sheet(isPresented: isDisplayedBind) { some sheet }