I am trying to set a default value in a text field but I don't know how.
//TextField("", text:$name)
struct MyView: View {
#State var name:String = ""
var body: some View {
TextField("", text:$name)
}
init(n:String) {
name = n
}
}
If I call MyView("Jack"), Jack does not appear as a value in the textfield.
This can be done in a following way
struct MyView: View {
#State var name: String
var body: some View {
TextField("", text:$name)
}
init(n: String) {
_name = State(initialValue: n)
}
}
Related
I'm trying to create a List that allows multiple selection. Each row can be edited but the issue is that since there's a tap gesture on the Text element, the list is unable to select the item.
Here's some code:
import SwiftUI
struct Person: Identifiable {
let id: UUID
let name: String
init(_ name: String) {
self.id = UUID()
self.name = name
}
}
struct ContentView: View {
#State private var persons = [Person("Peter"), Person("Jack"), Person("Sophia"), Person("Helen")]
#State private var selectedPersons = Set<Person.ID>()
var body: some View {
VStack {
List(selection: $selectedPersons) {
ForEach(persons) { person in
PersonView(person: person, selection: $selectedPersons) { newValue in
// ...
}
}
}
}
.padding()
}
}
struct PersonView: View {
var person: Person
#Binding var selection: Set<Person.ID>
var onCommit: (String) -> Void = { newValue in }
#State private var isEditing = false
#State private var newValue = ""
#FocusState private var isInputActive: Bool
var body: some View {
if isEditing {
TextField("", text: $newValue, onCommit: {
onCommit(newValue)
isEditing = false
})
.focused($isInputActive)
.labelsHidden()
}
else {
Text(person.name)
.onTapGesture {
if selection.contains(person.id), selection.count == 1 {
newValue = person.name
isEditing = true
isInputActive = true
}
}
}
}
}
Right now, you need to tap on the row anywhere but on the text to select it. Then, if you tap on the text it'll go in edit mode.
Is there a way to let the list do its selection? I tried wrapping the tap gesture in simultaneousGesture but that didn't work.
Thanks!
I have a SwiftUI app that produces a List made from elements of an array of columns held in a struct.
I need the items in the row to be editable so I'm trying to use TextEditor but the bindings are proving difficult. I have a working prototype however the TextEditors are uneditable - I get the warning:
Accessing State's value outside of being installed on a View. This will result in a constant Binding of the initial value and will not update.
Here's a much shortened version of my code which produces the same problem:
import SwiftUI
struct Item: Identifiable {
#State var stringValue: String
var id: UUID = UUID()
}
struct ArrayContainer {
var items: [Item] = [Item(stringValue: "one"), Item(stringValue: "two")]
}
struct ContentView: View {
#State var wrapperArray: ArrayContainer = ArrayContainer()
var body: some View {
List {
Section(header: Text("Test List")) {
ForEach (Array(wrapperArray.items.enumerated()), id: \.offset) { index, item in
TextEditor(text: item.$stringValue)
}
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
How can I bind the TextEditor to the items stringValues within the items array?
TIA.
#State should only be used as a property wrapper on your View -- not on your model.
You can use a binding within ForEach using the $ syntax to get an editable version of the item.
struct Item: Identifiable {
var stringValue: String
var id: UUID = UUID()
}
struct ArrayContainer {
var items: [Item] = [Item(stringValue: "one"), Item(stringValue: "two")]
}
struct ContentView: View {
#State var wrapperArray: ArrayContainer = ArrayContainer()
var body: some View {
List {
Section(header: Text("Test List")) {
ForEach ($wrapperArray.items, id: \.id) { $item in
TextEditor(text: $item.stringValue)
}
}
}
}
}
This could be simplified further to avoid the ArrayContainer if you want:
struct ContentView: View {
#State var items: [Item] = [Item(stringValue: "one"), Item(stringValue: "two")]
var body: some View {
List {
Section(header: Text("Test List")) {
ForEach ($items, id: \.id) { $item in
TextEditor(text: $item.stringValue)
}
}
}
}
}
I am just learning to code and I have a question. How do I store the Input data of a Textfield and display it in another View? I tried it with Binding but it doesn't work that way. I appreciate your help
import SwiftUI
struct SelectUserName: View {
#Binding var name: String
var body: some View {
TextField("Name", text: self.$name)
}
}
struct DisplayUserName: View {
#State private var name = ""
var body: some View {
// the name should be diplayed here!
Text(name)
}
}
struct DisplayUserName_Previews: PreviewProvider {
static var previews: some View {
DisplayUserName()
}
}
State should always be stored in a parent and passed down to the children. Right now, you're not showing the connection between the two views (neither reference the other), so it's a little unclear how they relate, but there are basically two scenarios:
Your current code would work if DisplayUserName was the parent of SelectUserName:
struct DisplayUserName: View {
#State private var name = ""
var body: some View {
Text(name)
SelectUserName(name: $name)
}
}
struct SelectUserName: View {
#Binding var name: String
var body: some View {
TextField("Name", text: self.$name)
}
}
Or, if they are sibling views, the state should be stored by a common parent:
struct ContentView : View {
#State private var name = ""
var body: some View {
SelectUserName(name: $name)
DisplayUserName(name: name)
}
}
struct SelectUserName: View {
#Binding var name: String
var body: some View {
TextField("Name", text: self.$name)
}
}
struct DisplayUserName: View {
var name : String //<-- Note that #State isn't needed here because nothing in this view modifies the value
var body: some View {
Text(name)
}
}
I'm trying to present a View in a sheet with a #Binding String variable that just shows/binds this variable in a TextField.
In my main ContentView I have an Array of Strings which I display with a ForEach looping over the indices of the Array, showing a Button each with the text of the looped-over-element.
The Buttons action is simple: set an #State "index"-variable to the pressed Buttons' Element-index and show the sheet.
Here is my ContentView:
struct ContentView: View {
#State var array = ["first", "second", "third"]
#State var showIndex = 0
#State var showSheet = false
var body: some View {
VStack {
ForEach (0 ..< array.count, id:\.self) { i in
Button("\(array[i])") {
showIndex = i
showSheet = true
}
}
// Text("\(showIndex)") // if I uncomment this line, it works!
}
.sheet(isPresented: $showSheet, content: {
SheetView(text: $array[showIndex])
})
.padding()
}
}
And here is the SheetView:
struct SheetView: View {
#Binding var text: String
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack {
TextField("text:", text: $text)
Button("dismiss") {
presentationMode.wrappedValue.dismiss()
}
}.padding()
}
}
The problem is, when I first open the app and press on the "second" Button, the sheet opens and displays "first" in the TextField. I can then dismiss the Sheet and press the "second" Button again with the same result.
If I then press the "third" or "first" Button everything works from then on. Pressing any Button results in the correct behaviour.
Preview
Interestingly, if I uncomment the line with the Text showing the showIndex-variable, it works from the first time on.
Is this a bug, or am I doing something wrong here?
You should use custom Binding, custom Struct for solving the issue, it is complex issue. See the Example:
struct ContentView: View {
#State private var array: [String] = ["first", "second", "third"]
#State private var customStruct: CustomStruct?
var body: some View {
VStack {
ForEach (array.indices, id:\.self) { index in
Button(action: { customStruct = CustomStruct(int: index) }, label: {
Text(array[index]).frame(width: 100)
})
}
}
.frame(width: 300, height: 300, alignment: .center)
.background(Color.gray.opacity(0.5))
.sheet(item: $customStruct, content: { item in SheetView(text: Binding.init(get: { () -> String in return array[item.int] },
set: { (newValue) in array[item.int] = newValue }) ) })
}
}
struct CustomStruct: Identifiable {
let id: UUID = UUID()
var int: Int
}
struct SheetView: View {
#Binding var text: String
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack {
TextField("text:", text: $text)
Button("dismiss") {
presentationMode.wrappedValue.dismiss()
}
}.padding()
}
}
I had this happen to me before. I believe it is a bug, in that until it is used in the UI, it doesn't seem to get set in the ForEach. I fixed it essentially in the same way you did, with a bit of subtlety. Use it in each Button as part of the Label but hide it like so:
Button(action: {
showIndex = i
showSheet = true
}, label: {
HStack {
Text("\(array[i])")
Text(showIndex.description)
.hidden()
}
})
This doesn't change your UI, but you use it so it gets properly updated. I can't seem to find where I had the issue in my app, and I have changed the UI to get away from this, but I can't remember how I did it. I will update this if I can find it. This is a bit of a kludge, but it works.
Passing a binding to the index fix the issue like this
struct ContentView: View {
#State var array = ["First", "Second", "Third"]
#State var showIndex: Int = 0
#State var showSheet = false
var body: some View {
VStack {
ForEach (0 ..< array.count, id:\.self) { i in
Button(action:{
showIndex = i
showSheet.toggle()
})
{
Text("\(array[i])")
}.sheet(isPresented: $showSheet){
SheetView(text: $array, index: $showIndex)
}
}
}
.padding()
}
}
struct SheetView: View {
#Binding var text: [String]
#Binding var index: Int
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack {
TextField("text:", text: $text[index])
Button("dismiss") {
presentationMode.wrappedValue.dismiss()
}
}.padding()
}
}
In SwiftUI2 when calling isPresented if you don't pass bindings you're going to have some weird issues.
This is a simple tweak if you want to keep it with the isPresented and make it work but i would advise you to use the item with a costum struct like the answer of swiftPunk
This is how I would do it. You'll lose your form edits if you don't use #State variables.
This Code is Untested
struct SheetView: View {
#Binding var text: String
#State var draft: String
#Environment(\.presentationMode) var presentationMode
init(text: Binding<String>) {
self._text = text
self._draft = State(initialValue: text.wrappedValue)
}
var body: some View {
VStack {
TextField("text:", text: $draft)
Button("dismiss") {
text = draft
presentationMode.wrappedValue.dismiss()
}
}.padding()
}
}
I was wondering whether I was able to get some help on this one, I've been trying a while to get things working and functioning properly and have been able to pass the Firestore data into the picker view, but I'm unable to select the data to view in the 'selected' area. I have added my code and my Firestore setup.
Thanks in advance.
import SwiftUI
import Firebase
struct SchoolDetailsView: View {
#ObservedObject var schoolData = getSchoolData()
#State var selectedSchool: String!
var body: some View {
VStack {
Form {
Section {
Picker(selection: $selectedSchool, label: Text("School Name")) {
ForEach(self.schoolData.datas) {i in
Text(self.schoolData.datas.count != 0 ? i.name : "No Schools Available").tag(i.name)
}
}
Text("Selected School: \(selectedSchool)")
}
}.navigationBarTitle("Select your school")
}
}
}
struct SchoolPicker_Previews: PreviewProvider {
static var previews: some View {
SchoolDetailsView()
}
}
class getSchoolData : ObservableObject{
#Published var datas = [schoolName]()
init() {
let db = Firestore.firestore()
db.collection("School Name").addSnapshotListener { (snap, err) in
if err != nil{
print((err?.localizedDescription)!)
return
}
for i in snap!.documentChanges{
let id = i.document.documentID
let name = i.document.get("Name") as! String
self.datas.append(schoolName(id: id, name: name))
}
}
}
}
struct schoolName : Identifiable {
var id : String
var name : String
}
Firestore Setup Image
To solve the issue with the code above the you can cast the tag to be the same type as the selectedSchool variable. This should then allow it to be selectable and is also safer as it uses optionals and allows the picker to be initially set to nil.
Example Code:
struct SchoolDetailsView: View {
#ObservedObject var schoolData = getSchoolData()
#State var selectedSchool: String?
var body: some View {
NavigationView {
VStack {
Form {
Section {
Picker(selection: $selectedSchool, label: Text("School Name")) {
ForEach(self.schoolData.datas.sorted(by: { $0.name < $1.name } )) {i in
Text(self.schoolData.datas.count != 0 ? i.name : "No Schools Available").tag(i.name as String?)
}
}
Text("Selected School: \(selectedSchool ?? "No School Selected")")
}
}.navigationBarTitle("Select your school")
}
}
}
}
As an alternative to the example above, you could also change the selectedSchool variable to be a schoolName type and cast the tag to be schoolName and this will also work. The only caveat with this approach is that the schoolName type must conform to the Hashable protocol.
Example Alternative Code:
struct schoolName: Identifiable, Hashable {
var id: String
var name: String
}
struct SchoolDetailsView: View {
#ObservedObject var schoolData = getSchoolData()
#State var selectedSchool: schoolName?
var body: some View {
NavigationView {
VStack {
Form {
Section {
Picker(selection: $selectedSchool, label: Text("School Name")) {
ForEach(self.schoolData.datas.sorted(by: { $0.name < $1.name } )) {i in
Text(self.schoolData.datas.count != 0 ? i.name : "No Schools Available").tag(i as schoolName?)
}
}
Text("Selected School: \(selectedSchool?.name ?? "No School Selected")")
}
}.navigationBarTitle("Select your school")
}
}
}
}
Either of these code examples should result in a working picker as follows:
Finally, as a side note for anyone when working with SwiftUI's default list view picker style, it must be enclosed within a NavigationView somewhere within the view hierarchy. This tripped me up when I first started using them :)