I have horizontal menu scrollView inside Parent vertical scrollView. When I select menu, it refresh it refreshes listView. But to fix parent scrollView content size, I need to refresh entire View (scrollView) by assigning menuItem selected id to parent scrollView.
Everything works as expected but as I have assigned menuItem id to parent scrollView to fix content size/height issue, animation for scrolling selected menu doesn't work.
Is there any way I can achieve this animation?
struct SampleScrollView: View {
// Parent scroll view to fit multiple sub-views
ScrollView(.vetical, showsIndicators: false) {
Vstack {
HStack {
ScrollView(.horizontal, showsIndicators: false) {
ScrollViewReader { proxy in
HStack {
ForEach(Menus, id: \.menuItem) { menu in
Button(action: {
// This animation is not working as parent scrollView gets assigned with this selected menuItem id on menu click which helps Parent ScrollView to get refreshed so parent scrollview content size get's refreshed based on content height of result list view.
withAnimation {
proxy.scrollTo(menuItem, anchor: .leading)
}
LoadList()
}) {
Text("Option \(menuItem)")
}
}
}
}
}
}
VStack {
ScrollView(.vertical, showsIndicators: false) {
LazyVStack {
ForEach(resultArray, id: \.self) { item in
Text(item.title)
}
}
}
}
// Some other views here
VStack { }
}.id(menuItem) // Parent ScrollView Id get's updated every time when menu button selected
}
}
Related
I have a LazyVGrid inside a NavigationView.
NavigationView {
ScrollView {
LazyVGrid(columns: columns) {
ForEach(items) { item in
NavigationLink(tag: item, selection: $displayedItem) {
DetailView(item)
} label: {
GridItemView(item)
}
}
}
}
}
The referenced variables are defined as follows on the view:
#State var displayedItem: Item?
let columns: [GridItem] = Array(repeating: .init(.flexible()), count: 2)
Now I want to show the detail view for a specific item. I do this by simply assigning this item to the displayedItem property:
func showDetailView(for item: Item) {
displayedItem = item
}
This works great when the respective item is visible on the LazyVGrid at the moment when I call this function. However, when the item is not visible, I first need to scroll to the item for the NavigationLink to fire. I know why this is happening (because the items are loaded lazily, it's a lazy grid after all), but I don't know how to make the LazyVGrid load the specific item when I need it.
What I've tried:
I have also tried to programmatically scroll to the target item by wrapping the entire ScrollView inside a ScrollViewReader and appending the following modifier:
.onChange(of: displayedItem) { item in
if let item = item {
scrollProxy.scrollTo(item.id)
}
}
Unfortunately, this has the same problem: Scrolling to a given item doesn't work until the item is loaded.
Question:
Is there any way to make this work, i.e. to trigger a NavigationLink for an item that is not currently visible in the LazyVGrid? (It's important for me as I need this functionality to deep-link to a specific item's DetailView.)
An possible approach can be like in this topic - use one link somewhere in background of ScrollView and activate it by tapGesture/button from user or assigning corresponding value programmatically.
Tested with Xcode 13.4 / iOS 15.5
Main part:
ScrollView {
LazyVGrid(columns: columns) {
ForEach(items) { item in
RoundedRectangle(cornerRadius: 16).fill(.yellow)
.frame(maxWidth: .infinity).aspectRatio(1, contentMode: .fit)
.overlay(Text("Item \(item.value)"))
.onTapGesture {
selectedItem = item
}
}
}
}
.padding(.horizontal)
.background(
NavigationLink(destination: DetailView(item: selectedItem), isActive: isActive) {
EmptyView()
}
)
.toolbar {
Button("Random") { selectedItem = items.randomElement() }
}
Test module on GitHub
I am writing a SwiftUI iOS app where I need a Text view to automatically scroll to the end of its content whenever the content is updated. The update happens from the model. To not complicate this question with the details of my app, I have created a simple scenario where I have two text fields and a text label. Any text entered in the text fields is concatenated and shown in the text label. The text label is enclosed in a horizontal ScrollView and can be scrolled manually if the text is longer than the screen width. What I want to achieve is for the text to scroll to the end automatically whenever the label is updated.
Here is the simple model code:
class Model: ObservableObject {
var firstString = "" {
didSet { combinedString = "\(firstString). \(secondString)." }
}
var secondString = "" {
didSet { combinedString = "\(firstString). \(secondString)." }
}
#Published var combinedString = ""
}
This is the ContentView:
struct ContentView: View {
#ObservedObject var model: Model
var body: some View {
VStack(alignment: .leading, spacing: 10) {
TextField("First string: ", text: $model.firstString)
TextField("Second string: ", text: $model.secondString)
Spacer().frame(height: 20)
Text("Combined string:")
ScrollView(.horizontal) {
Text(model.combinedString)
}
}
}
}
From the research I have done, the only way I have found to scroll to the end of the text, without having to do it manually, is to add a button to the view, which causes the text in the label to scroll to the end.
Here is the above ScrollView embedded in a ScrollViewReader, with a button to effect the scrolling action.
ScrollViewReader { scrollView in
VStack {
ScrollView(.horizontal) {
Text(model.combinedString)
.id("combinedText")
}
Button("Scroll to end") {
withAnimation {
scrollView.scrollTo("combinedText", anchor: .trailing)
}
}
.padding()
.foregroundColor(.white)
.background(Color.black)
}
}
This works, provided the intention is to use a button to effect the scrolling action.
My question is: Can the scrolling action above be triggered whenever the model is updated, without the need to click a button.
Any help or pointers will be much appreciated.
Thanks.
I assume you wanted this:
ScrollViewReader { scrollView in
VStack {
ScrollView(.horizontal) {
Text(model.combinedString)
.id("combinedText")
}
.onChange(of: model.combinedString) { // << here !!
withAnimation {
scrollView.scrollTo("combinedText", anchor: .trailing)
}
}
}
}
ScrollViewReader is the solution you're looking for. You may need to play around with the value. Also you'll need to add the .id(0) modifier to your textview.
ScrollView {
ScrollViewReader { reader in
Button("Go to first then anchor trailing.") {
value.scrollTo(0, anchor: .trailing)
}
// The rest of your code .......
I have a list inside a view. Inside the list, items are iterated through to populate the list. When you click on each list item, I want to navigate to another view.
This is working as expected but I want to have a Button represented by a circle in each list item that can be clicked independently without navigating to the second view. Right now, clicking the circle just takes me to 2nd view. How can I accomplish this?
var body: some View {
NavigationView {
List {
ForEach(items) { item in
NavigationLink(
destination: OtherView(name: "test"),
label: {
Text("Navigate")
})
HStack {
Image("1")
.resizable()
.frame(width: 32.0, height: 32.0)
Button(action: addItem) {
Label("Add Item", systemImage: "circle")
}
}
}
}
}
}
You can not do this with List. You can use VStack or LazyVStack inside a ScrollView as an alternative solution
I want to have a scrollable list that when each row is tapped, it takes you to a different view. Inside each row, I want to have a heart button that when tapped overrides the navigation behavior and just toggles a heart fill/unfill.
As an alternative to do this, would it make sense to use a ScrollView inside a NavigationView and then have each list item be a VStack?
Pseudocode hierarchy:
NavigationView {
ScrollView {
VStack {
// Button
}
}
}
Is there a better way ( or more preferred way) to accomplish this?
Use LazyVStack
let items = ["A","B"]
var body: some View {
ScrollView {
LazyVStack(spacing: 10) {
ForEach(items, id: \.self) { item in
Text(item)
}
}
}
}
I tried to make a horizontal scrollview that contained a list of item. when I clicked any of the item, it will show a border(highlight) behind the item. When I press another item, the previous border disappear and the latest clicked item appear the border. It just looks like a selection horizontal scrollview. I have no idea about how to do so.
ScrollView(.horizontal, showsIndicators: false){
LazyHStack{
ForEach(self.staffs.indices, id: \.self){ staff in
VStack{
Image(staff.image)
.resizable()
.frame(width: 100, height: 100)
.clipShape(Circle())
}
.onTapGesture {
print(createBookingJSON.staffs[staff].staffID!)
}
}
}
}
Convert your VStack into a standalone view, then pass a Binding to it that can be read from the Parent View. Your new VStack standalone view needs an OnTapGesture or an Action through a button to toggle it's state. We will make your ForEach a "single selection" list as you request.
NEW View to use inside your ForEach:
struct ItemCell: View {
var item: Item
#Binding var selectedItem: Item?
var body: some View {
VStack{
Image(item.image)
.resizable()
.frame(width: 100, height: 100)
.border(Color.green, width: (item == selectedItem) ? 20 : 0)
}
.onTapGesture {
self.selectedItem = item
print(createBookingJSON.staffs[staff].staffID!)
}
}
}
Now in the view that contains your Foreach, add a State Var of selectedItem so you can read the Binding you created in your cells. And Replace your VStack with your new ItemCell:
struct YourParentView: View {
#State var selectedItem: Item? = nil
var body: some View {
ScrollView(.horizontal, showsIndicators: false){
LazyHStack{
ForEach(self.staffs.indices, id: \.self){ staff in
ItemCell(item: staff, selectedItem: self.$selectedItem)
}
}
}
}
}
Now when you click on the item, a border should appear. You may need to play with the border depending on your design, and the clipShape you have used of Circle(). Good Luck comrade.