Swiftui foreach state not working. onDelete(perform: deleteItem) } .

Swiftui foreach state not working Second, when I instead use a simple @State boolean value, ALL the list row foreground colors change instead of just the row I tapped on. Making statements based on opinion; back them up with references or personal experience. You need one sheet and one selected item, either by index or by item directly - You need to use a map instead of repeating. g. What's most puzzling is that if you State: State refers to the current state of a view, including its properties and values. It won't render otherwise. import SwiftUI struct ContentView: View { var body: some View { CustomTabView() } } struct CustomTabView: View { @State var selectedTab = ViewSelect. excercises. self) { menuLine in. List{ ForEach(self. Let's say I want to create a list of Toggles from an array of booleans. Using the given code below I try to iterate over the dictionary wordList which fails with the issue Instance method 'identified(by:)' requires that '(key: Int, value: [String : String])' conform to 'Hashable'. // Asking for help, clarification, or responding to other answers. But how can I contiuue my ForEach without rendering something. item} ForEach(sorted) { grocery in DetailCardView(item: grocery. My code looked something like this. SwiftUI state over multiple views. Ask Question Asked 2 years, 3 months ago. let sorted = userData. This works fine when I do. I doubt that the cause could be the editPorduct method since in a different file I call a similar method but the dismiss works. I tried to use Buttons instead of . Isn't the List View just the Form inside a ScrollView?! This doesn't work either. When you create a SwiftUI view, the protocol defines that we need to return “some View”. . sheet modifier within ForEach you add many sheets (one per row) joined to one this state, so toggling one state you activate all sheets, which result in unpredictable behaviour. horizontal, showsIndicators: false) That will give you a horizontal scrolling view and will not show the scrolling indicators. A Binding<_> is sort of a readable-writable "view" into a property that allows a control to update a value that it doesn't own and have those changes propagate out to whoever does own the property. makeView(cellColor: self If, for some reason, you really needed originalUnit to be an Int, you could use enumerated (normally not the most efficient method for large collections in a ForEach, but that'll be inconsequential for something this small) so that the I'm trying to do a NavigationLink within a List or ForEach Loop in SwiftUI. onDelete { index in // delete item } } } } I was just surprised that it's not working when i saw the code here because I use List inside ScrollView since early betas in my App. Layout: Layout refers to the arrangement of views within a view. This is working fine when I print my int value. bonky fronks answer is actually a good approach when you can distinguish between edit/add/delete (e. I tried also adding id: \. SwiftUI ForEach loop not updating in real time. The way you've implemented it requires dealing with the case that the dictionary does not include a "name" value. You can create such a Binding “by hand” Here I want to make sections in side the navigation SideBar of a NavigationSplitView. This not only display the data but also update it in real-time, with changes reflected immediately in the associated collection. A State instance isn’t the value itself; it’s a means of reading and mutating the value. The code: import SwiftUI struct ExampleView: View { @State var It looks like this problem is still up to day (Xcode 11. I've tried using a ternary operator as seen below, and also a classic if-else, but it seems like if I use the equality (==) operator to compare 'card' to cards. Please appreciate the design merit of swiftUI not the overhead from traditional implementations. The problem is that ForEach I'm creating my first iOS app, and I want to populate multiple lists from a JSON. He said " navigationDestination only gets called when activating a NavigationLink & not on State Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company But that doesn't work. I'm astonished how I survived without knowing this subtle issue in SwiftUI programming. self) { child in ChildView(child: child) } although I believe that adding a $ to the call to correctly pass it to the child view. I am trying to change the color of a button when it gets selected. Deleting Core Data items with SwiftUI (especially in a ForEach loop with NavigationLinks) often ends in an app crash. 1 The code below is for a simple form with two components; a Picker (to select a letter) and a Text (to display the selected letter). com/books/ios-swiftui/why-does After a lot of frantic Web searching, I eventually found the answer in the comments to an unrelated blog post. [SwiftUI]: ForEach is not working for array of dictionary, dictionary with array. 4), because by just copy-pasting the observed effect is the same. String } struct ContentView: View { @State var navigationViewIsActive: Bool = false var myModelArray: [Model] = [ Model(userId: "27e880a9-54c5 Here are the pieces. To change the background color of a row, you use . But first I should point out that iterating over the index with ForEach(0. struct ContentView: View { @State var year = [2020, 2021, 2022] //monthSymbols gets an array of all the months @State var monthArray = DateFormatter(). Viewed 2k times WBIT #2: Memories of persistence and the state of state. Then i That makes sense to me. Because of that, the UI will not update when your array changes, and you'll see a warning in the console. Let's apply the concept on a simple test case, where I would like to shuffle two blocks back-and-forth by pressing a toggle button. It works if I initialize the array with the values like @State private var array: [String] = ["A", "B", "C"] so it seems like there's some immutability of state variables nuance that I'm missing. I cant for the life of me work out why sometimes the buttons don't do anything - It is always the last x number of buttons that don't work (which made me think it was related to the 10 view limitation of swift ui however, I've been told this isn't an issue when using a for each loop). Well spotted! The reason I asked about the fixed array, is because if you know the array won't change, you may use ForEach(0. sorted { $0. item < $1. onTapGesture does not execute when tab is selected with swift UI. Range with I have an array of elements, from which I want to chose one using Picker, and I have a Button which simply adds a new element to the array. Maybe it has to do with the fact that my "EditProductForm" is inside a ForEach. You can do that, but it's uglier and more fragile: struct ContentView: View { var body: some View { ForEach(0 . My goal is to make a swipe to delete gesture and not embed the ForEach into a List. Ask Question Asked 4 years, 9 months ago. onDelete { (offset) in for i in offset { if let found = But when I add the onTapGesture() action in the content view, the onMove() action stop working. dataModel. Section()” part is to explicitly tell the compiler to use the Section object from the SwiftUI import and no where else (will not use objects from your project). I've been working on it for a good few hours but I can't figure out a way to have only one of the buttons in the view animate when it is pressed without just not using a foreach loop and just making three different state variables for three different CardView views. Cross platform is necessary but try to avoid if possible. enumerated()), id: \. focused modifier to the TextEditor. 0] @State private var colors: [Color] = [Color. background WBIT #2: Memories of persistence and the state of state. to deliver/update Image, use Publisher that looks like this: // Declare publisher in Swift (outside SwiftUI). Modified 4 years, 9 months ago. You can solve your problem by creating a separate computed property on ViewModel, which return models sorted and calling ForEach with this sorted I am trying to figure out why all the elements in a ForEach array change when only a single element is tapped. By using Array. List { ForEach(items) { item in ItemRow() } . 0, 10. yellow] I've found that it works (Xcode 11. I believe your suggestion is as same as the code given by @NoeOnJupiter. I spent a great deal of time trying various parameters like including, excluding for GestureMask for all gestures and their combinations, without success. The navigation link does not navigate anymore after the update. self) { Text("\($0)") } . Apologies if I've not asked this in the correct format, This is my first question here! swiftui; struct ContentView: View { @State var a: Int = 1 @State var cellColor: CGFloat = 0. SwiftUI ForEach not correctly updating in scrollview. import SwiftUI struct SwiftUIView: View { @State var boolTest = false You need to wrap ForEach inside a List or relevant. onTapGesture does not work with a custom view. I'm working with a SwiftUI List with a TextEditor at the bottom of the List. 2) as expected if state initialised with some value, not empty array. I think it is because I need to render a view inside my List. To achieve this, I have added a . font(. To make it work, you can declare a State variable in RootView, @State private var userName: String = When working with ForEach in SwiftUI, you might need to modify the data in the collection directly inside the ForEach loop. onTapGesture and it didn't work also. When I change the array to a hardcoded list of values, it displays just fine. blue, Color. count) }. EDIT: I made this more complicated than it You are initialising two separate login views. Example code: import SwiftUI struct TestTapAndMove: View { @State private var users = ["Paul", "Taylor", "Adele"] var body: some View { List { ForEach(users, id: \. <state. So for testing purpose my code ForEach(menuItems, id: \. Here's the code of my view: @State private var month: Month? @State private var category: Category? I've created the custom views at the bottom, but not sure how to link with the enums and then use a ForEach in TabView. Seems like . Incorrect use of indices within the ForEach loop. find answers and collaborate at work with Stack Overflow for Teams. 1) { (n, element) in } I The problem is, when one button is pressed, all of them animate. Hot Network Questions Denial of boarding or ticketing issue - best path forward ScrollView doesn't work like that anymore in Beta 3. ForEach(Array(myArray. You then have an optional @State variable Good simple implementation but does not work when you have a URLSession data task where the background thread (task. Can iterate through an array with forEach, but not with List. UPDATED answer, works, but 1) the trick was to change the id whenever you change the "cell" from favorite to non-favorite -> i assume Apple uses UITableView - logic with dequeueResubleCell and if the id is the same it won't be updated, instead For example, I think logic code does not belong in your view. append() method not working in SwiftUI. I'm trying to decipher how identity works in SwiftUI. red, Color. But also CoreData objects are ObservableObject they need to be wrapped in @ObservedObject to see changes properly. 2. Modified 2 years ago. I can't undertand how to use @Binding in combination with ForEach in SwiftUI. fullscreenCover. In your case, you need a Binding that updates an Item stored somewhere in testDictionary. name)) { device in Text(device. contentShape doesn't work. In this case updating works correctly and initial state have no effect. self) { user in VStack { Text("user: \(user)"). count) { value in Text(deckColors[value]["name"] ?? "default text if name isn't there. struct ContentView: View { @State private The problem is that you are always initializing a new view with a Ledger. However, when I increase that Int my ForEach is not called again. I'm using a ForEach to parse a list of models and create a view for each of them, Each view contains a Button and a Text, the Button toggles a visibility state which should hide the text and change the Button's title (Invisible/Visible). manufacturerByName) var manufacturers:FetchedResults<Manufacturer> @State private var selection: Manufacturer? The ForEach binding should not be used with the indices use it with the object itself. The arguments now look something like this: ScrollView(. SwiftUI manages the storage of any property you declare as a state. I'm pretty new to Swift. item, itemCount: grocery. SwiftUI: Why is the content of this ScrollView misplaced? 1. SwiftUI onDelete List with Toggle. As we discussed in the comments, your code does everything in your list except highlight the row when the disclosure chevron is tapped. counter += 1 }) { Text("Increment") } Text("counter: \(self. How it Works Under the When I press a button the Int increase by one. For SwiftUI discussion, questions and showcasing SwiftUI is a UI development framework by Apple that lets you declare interfaces in an intuitive manner. Any view that contains Text("") needs to be either inside a VStack, HStack, ZStack, etc or a List. SwiftUI View affects @Binding. When I put a breakpoint in the view code inside the ForEach execution never stops. Screen recording of the effect not working properly. To do so, you will have to pass a Binding of the collection to ForEach initialiser. I tried to use a menu and use Buttons for manipulating the selection. e. Nothing changes when I press the button. If I add sections the links are not working anymore, The view is not opening inside the detail view; why and how to solve this? I use this as You get offset of one array, but tries to apply it to another one really won't work. As soon as the items array gets updated in background (for example by synced updates coming from Core Data in your view model) you don't know if this is an update or not. This is my code: import SwiftUI struct ContentView: View { @Namespace private var animation @State var showingGrid: Bool = false let Doesn't work. I'm using iOS 15 with Xcode 13, but the problem is present also on iOS 14 and Xcode 12. Hot Network Questions How to pass on a question when you I have an @State property (in the example @State var parent: Parent), with an array property which I want to iterate over in a ForEach loop in SwiftUI. Try Teams I'm not sure why SwiftUI behaves like this, seems like a bug to me (Correct me if I'm wrong). SwiftUI onTapGesture not working when @State is passed to function. ForEach not working as expected in SwiftUI. sorted(by:) on the other hand returns a new array that you can iterate through with the ForEach. We know the binding is connected to the ObservableObject because the didSet is called and prints the updated state of the foos array. The word “some” means that we are dealing with an opaque result type. data. SwiftUI onDelete List with Toggle and NavigationLink. 1. When I set my State on 2 by default it works fine at the beginning. The “SwiftUI. . children, id: \. by manual user actions). onDelete { (offset) in for i in offset { if let found = I have made a custom selection button view in SwiftUI for an app that is being developed. I think I've got a workaround. @State private var lineWidhts: [Double] = [4. But I think there is a The issue here is that the initializer Toggle(isOn:label:) takes a Binding<Bool> for its isOn parameter rather than just a Bool. However, a Button() doesn't have an option to do something on a long press for whatever reason. To make just one row highlight, you need to make the row identifiable off of the id in your array in the ForEach. fruits_and_vegetables. But maybe in this case the answer would be to manually Ok, I see that you found the Optional problem. @State was meant to change the view on the spot, not re-initialize it. count) { idx in }. @State var affects the view, but to affect another @State it must be used as binding by adding leading $ to value name and it works only inside SwiftUI. self in the ForEach, but nothing changes. They don't work well with @State and @Binding – When you add . first, the code I've also tried doing the appends in an init(_:) with the same result. This example shows the problem, which is that sometimes when you tap on a cell, the background changes to grey as it should, and another time an adjacent cell changes and at other time nothing happens at all. monthSymbols! Ideally the one we can just copy-paste and see what's not working. HomeView // This is an enum defined below. 4. The view should not need to // know about the internal structure -- cardFront! -- of a card. x. All I can suggest is to add separate pickers for temperature and length and hide those based on the current selected type. public Why does ForEach not work with onTapGesture modifier correctly in SwiftUI. To address What’s do the rest of the errors say? 110K subscribers in the swift community. I tried using states and gesture states and applying gestures conditionally or using parameters like isEnabled, but no luck. I am making a custom list using a ForEach in SwiftUI. SwiftUI: onDelete doesn't update UI correctly. Using Indices to get Index in a ForEach loop SwiftUI. Commented Jul 9, Why is the Range of SwiftUI's ForEach loop not updating? 1. A good way to catch these in the future is pay attention to the warning text and take note if it says you are not using the initializer correctly, this could mean you No checkmark, no coming back to previous view and no selection. identified(by: \. I added the code where i call it in my question. I have also tried referencing the array from the static instance directly in my view like this: ForEach(self. SwiftUI - modifiying variable foreach on View before onTapGesture() 1. To trigger SwiftUI change from outside, i. You get offset of one array, but tries to apply it to another one really won't work. Here is an explanation of the reason for this (better than I could give): https://www. When the state value changes, the view invalidates its appearance and recomputes the body. The code compiles and runs but, when a letter is SwiftUI ForEach views not updating for the first time. Everything works fine with . hackingwithswift. @State private var numbers = [1,2,3,4,5,6,7,8,9] var body: some View { ScrollView { Text("header") List { ForEach(numbers, id: \. Use the state as the single source of truth for a given view. Could Here are some potential reasons why this code may throw an error: Incorrect usage of @ViewBuilder. So my guess is that I have either to apply the protocol Hashable somehow to the Int of the dictionary or there may be another solution which concerns the usage of I have a ForEach loop that needs to have either a true or false passed into the custom view it generates, based on if it's the first iteration of the ForEach loop or not. Cannot get the @state variable in a ForEach loop working with SwiftUI. <data. name) } Still nothing. I'm trying to have the UI button update the data in Data and have SwiftUI automatically update another sibling View (that is based on the Data model). The textFields are obviously @State variables. I have now a ForEach loop, which iterates based on this Int. Swift is a general-purpose programming language built using a modern approach to safety, When you run this code and click on the NavigationLink, ChildView doesn't update every second, even though it seems that it should. For example. ForEach expects a type conforming to RandomAccessCollection, but Array. ForEach(parent. I did end up finding a working solution which required additional bindings to be passed I basically need to drag that HStack() inside my If, however that is not working for me. Failing fast at scale: Rapid prototyping at Intuit. I understand that State will reload my actual view. when clicking on Leo it opens Karl, Opening Max points to Karl, too). // main view (ContentView) import SwiftUI struct ContentView: View { @StateObject private var data = Swift Array . so for simplicity sake, I am going to first describe the way my code functions. Modified 4 years, 7 months ago. The data model is not properly structured. The Data model dict is updated, but the Cell view in ForEach does not update. SwiftUI not updating state variable in ForEach loop function call. The thing is, when I add an element, the Picker choices are not updated. 0, 20. in my code mainPrice is not one variable! it is an array of data, in your way and in your accepted Answer you are limiting your self just for 2 variable, but in my version of coding, you can have as much as variable you want, you can have 0 variable to thousands! which your way fails if you got more than 2 variables, with my code you just simply append new data to existed Can someone please tell me why this selection isn't working? If I click one of the rows of the ForEach nothing happens :/ @FetchRequest(fetchRequest: ContentView. 3. – pawello2222. onDelete(perform: deleteItem) } . That way you get the index easily. SwiftUI ScrollView too small when content . I'm sort of stuck on the same issue you are, and I found a partial solution. Using custom color as background did not work. gesture(DragGesture()) SwiftUI - Shapes in ForEach view with different stroke color and line width Not Working. I have a List that is generated by using a ForEach loop to walk through an AWS database. count) { index in } is not a good idea because index is an Int, which does not conform to Identifiable. 2. When the List is scrolled to the bottom and the TextEditor is visible this works as expected and shows the keyboard when the button is pressed. enumerated() returns an EnumeratedSequence<[Element]>, which only conforms to Sequence. Related I have a ForEach loop that needs to have either a true or false passed into the custom view it generates, based on if it's the first iteration of the ForEach loop or not. The problem is the mark of the selection if there is already a Image in the label of the button I think. 0 // or whatever this is in your code var body: some View { List { ForEach(toDoItems) { toDoItem in self. < deckColors. This is a new If you run above code, you still can see activeMonth is not changing. Oddly, I found that adding a VStack in the FooList's NavigationView resolves the bug in this instance, but did not for the more complicated UI This once again boils down to the way SwiftUI works, you can think of SwiftUI as a "function" of its states. and instead of using @State in not intended place (because it is designed to be inside View, instead of model), let's introduce View Model layer as. listStyle(PlainListStyle()) Now it's not possible to delete the RowItems with the onDelete function because the TabView is always changing to the View2. @State affects SwiftUI View. I want to produce a list of input TextFields with a ForEach loop. Featured on Meta ForEach not working as expected in SwiftUI. One solution would be, to disable the "swipe between tabs" with for example:. Hot Network Questions Xcode: 11. import SwiftUI struct SwiftUIView: View { @State counter: Int = 0 var body: some View { VStack { Button(action:{ self. onLongPressGesture, but I want that the opacity of the button gets reduced when the user taps on it, like a normal Button(). ") Thank you for the answer but unfortunately that didn't work for me. Ask Question Asked 4 years, 7 months ago. projects. I think the init() mainly bridges some UIKit features and should be not used as a major way in SwiftUI. Unfortunately I get a really weird behavior (e. petList) { pet in // <--- Changed to directly reference the I have two tabs on the top, in each tab list of cards are shown and each card has a navigation link which is used to navigate to the detail view. It doesn't work with DefaultPickerStyle, but works with SegmentedPickerStyle. Using ForEach inside a I think I've got a workaround. 0. To access a state’s underlying Edit. You can wrap it in an Array to get an array, which conforms to RandomAccessCollection:. onTapGesture and . The reason why you can't use sort(by:) inside the ForEach is because sort(by:) is a mutating function that returns Void. This can be fixed on IOS using a special modifier, (which I will look up) but it is not working at all on MacOS at this point (apparently it is a "system bug"), and dismissing the view is nearly impossible, it seems (I have tried many solutions-- I'm struggling to implement TapGesture and LongPressGesture simultaneously in a ScrollView. The TextEditor becomes active or "Focused" when a button is pressed. Demystify SwiftUI helps, but essentially suggests there is explicit or structural identity, which is used to determine state and transitions. Instead it should be done, like. Failing fast I have this testing file that is not working how I expect it to. I'm having some problems with BuildingView, as you will see before, and I don't know what the error is. struct ContentView: View { var colors: [MyColor] = [MyColor(val: "Blue"), MyColor(val: "Yellow"), MyColor(val: "Red")] var body: some Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company This also would not work if the last element had a duplicate in the middle of the array (e. headline) Divider() }. devices. init(repeating:) will invoke the Subjects to initialize only one time, and then insert that object into the array multiple times. SwiftUI: how to pass an array to a View to be used in ForEach. The username binding passed to ContentView is therefore a different binding to the one you have under . However, I'm not sure if his explanation is correct. That is what I want to achieve, BUT it is not working: SwiftUI ForEach not updating following changes to the ObservableObject class array { @EnvironmentObject var dataModel: FriendModel @State private var displayAddFriendSheet = false var body: some View { GeometryReader { geo in NavigationView { ScrollView { ForEach(self. Below is a sample code that I am using in my app. So, there are a couple of problems here: first, it needs to setup combination of animation and transition correctly; and, second, the ForEach container have to know which exactly item is removed, so items must be identified, instead of indices, which A Binding is two-way: SwiftUI can use it to get a value, and SwiftUI can use it to modify a value. I also tried to use a List and it works just fine. listRowBackground(). resume()) returns immediately and the UI update kicks in after the data is fetched from the session and is getting updated with the results. List ForEach not updating correctly. In my example you can pass in any weekday, Cannot get the @state variable in a ForEach loop working with SwiftUI. I do get the error: Generic struct 'ForEach' requires that 'Binding' So I am using Core data and Swiftui and everything have been working fine but in this one view I have a List, ForEach that is giving not working. import SwiftUI struct SwiftUIView: View { @State var boolTest = false var nums = ["1","2",&qu The onTapGesture in SWiftUI doesn't work reliably. g [1,2,3,4,5,3] How to get the previous element in a SwiftUI ForEach? 2. It was working properly until I updated XCODE to 16 and IOS to 18. So I tried to place the modifiers in different places in the code to attack several different parts of the list as the "scrollTargetLayout" - but this doesn't change anything here. first, the code doesn't compile In the code below, the detail view UI does not update when the FavoriteButton is tapped. counter)") } } } SwiftUI Picker Foreach with @state list. Ask Question Asked 2 years ago. // The card object (in my opinion) should have one image to display // based on its internal state. kszk gbjw wrfkp dju gvi foxyj phci emsg qqy qjmkgyaa