I use the library RKmanager to show a calendar with a dateRangePicker. But i can't get an event if the parameter rkManager.endDate is set from nil to a date.
I want activate and deactivate an addButton for the dateRange if a range is set.
The Object from i want to get the trigger if changes:
class RKManager : ObservableObject {
#Published var startDate: Date! = nil
#Published var endDate: Date! = nil
Now my View:
import SwiftUI
struct DateRangeView: View {
#State var rkManager = RKManager(calendar: Calendar.current, minimumDate: Date(), maximumDate: Date().addingTimeInterval(60*60*24*365), mode: 1)
#State private var addNewDateRangeIsDisabled: Bool = true
var body: some View {
VStack(alignment: .leading) {
RKViewController(isPresented: .constant(false), rkManager: self.rkManager )
Button(action: {
if self.rkManager.endDate != nil
&& self.rkManager.startDate != nil
{
self.addNewDateRange()
}
}) {
HStack {
Image(systemName: "plus.circle.fill")
.resizable()
.frame(width: 20, height: 20)
Text("Add new DateRange")
}
}
.padding()
.disabled(self.rkManager.endDate == nil) // --> here i want to change if the value changed
}.navigationBarTitle("TestRoomName", displayMode: .inline)
}
A ObservableObject should be represented in view by ObservedObject dynamic property wrapper so view would be updated on published property change.
Here is fix
struct DateRangeView: View {
#ObservedObject var rkManager = RKManager(calendar: Calendar.current, minimumDate: Date(), maximumDate: Date().addingTimeInterval(60*60*24*365), mode: 1)
// ... other code
Related
I am trying to make a view that updates based on if the user toggles the favorite button or not. I want the entire view to reconstruct in order to display an array of values whenever that array of values is changed. Inside the view, a for each loop should display every value in the array.
The view that I want to update every time savedArray is changed is FavView. But when I try to use a foreach loop to display every value is savedArray(which I created as a #Published so the view would reconstruct), it gives me the error Generic struct 'ForEach' requires that 'Published<[String]>.Publisher' conform to 'RandomAccessCollection'. I am confused because I thought that String arrays were able to be used in for each loops. Is this not true? How do I loop through a #Published array? Thank you!
This is my code for the savedArray(in ViewModel) and the FavView I want to display it in with the for each.
struct ContentView: View {
#StateObject private var statNavManager = StatsNavigationManager()
#State private var saved: [String] = []
var body: some View {
TabView {
StatsView(saved: $saved)
.tabItem {
Label("Home", systemImage: "house")
}
FavView(saved: $saved)
.tabItem {
Label("Saved", systemImage: "bookmark")
}
}
.environmentObject(statNavManager)
}
}
final class ViewModel: ObservableObject {
#Published var items = [Item]()
#Published var showingFavs = true
#Published var savedItems: Set<String> = []
#Published var savedArray: [String]
// Filter saved items
var filteredItems: [String] {
//return self.items
return savedArray
}
var db = Database()
init() {
self.savedItems = db.load()
self.items = db.returnList()//the items
self.savedArray = Array(db.load())
print("savedarray", savedArray)
print("important!", self.savedItems, self.items)
}
func contains(_ item: Item) -> Bool {
savedItems.contains(item.id)
}
// Toggle saved items
func toggleFav(item: Item) {
print("Toggled!", item)
if contains(item) {
savedItems.remove(item.id)
if let index = savedArray.firstIndex(of: item.id) {
savedArray.remove(at: index)
}
} else {
savedItems.insert(item.id)
savedArray.append(item.id)
}
db.save(items: savedItems)
}
}
struct FavView: View {
#StateObject private var vm = ViewModel()
var body: some View {
VStack {
List {
var x = print("testing",vm.savedArray)//this only prints once at the start
ForEach($vm.savedArray, id: \.self) { string in
let item = vm.db.returnItem(input: string.wrappedValue)
HStack {
VStack(alignment: .leading) {
Text(item.title)
.font(.headline)
Text(item.description)
.font(.subheadline)
}
Spacer()
Image(systemName: vm.contains(item) ? "bookmark.fill" : "bookmark")
.foregroundColor(.blue)
.onTapGesture {
vm.toggleFav(item: item)
}
}
}
}
.cornerRadius(10)
}
}
}
in ForEach, you are using $ symbol to access savedArray you have to use the vm itself
struct FavView: View {
#StateObject private var vm = ViewModel()
var body: some View {
VStack {
List {
ForEach($vm.savedArray, id: \.self) { string in //< here $vm.savedArray not vm.$savedArray
let item = vm.db.returnItem(input: string)
HStack {
VStack(alignment: .leading) {
Text(item.title)
.font(.headline)
Text(item.description)
.font(.subheadline)
}
Spacer()
Image(systemName: vm.contains(item) ? "bookmark.fill" : "bookmark")
.foregroundColor(.blue)
.onTapGesture {
vm.toggleFav(item: item)
}
}
}
}
.cornerRadius(10)
}
}
}
this should work.
I have a view that makes an API call to pull nearby restaurant data and display it in a list. I've placed a button in the navigation bar of that view to display a sheet which will ultimately show the user filter options. For now, it uses a Picker placed in a form to allow the user to pick how they want to sort the results. I am using a variable with a #Binding property wrapper in the filter view to pass the selected value to a #State variable in the restaurant data view (selectedOption). It all works great until the view is reloaded. Either by going to a different view or relaunching the app. It appears the selectedOption variable in my API call in the onAppear function of the restaurant data view is being reset to what I've set the default value to when I defined the #State variable. I am wondering if there is a way to persist the value of what was chosen in the filter view through view reloads of the restaurant data view.
Restaurant data view:
import SwiftUI
import SwiftyJSON
import SDWebImageSwiftUI
struct RestaurantsView: View {
#EnvironmentObject var locationViewModel: LocationViewModel
#EnvironmentObject var venueDataViewModel: VenueDataViewModel
#State var selectedOption: String = "rating"
#State private var showingSheet = false
#State private var searchText = ""
#State private var showCancelButton: Bool = false
var body: some View {
let CPLatitude: Double = locationViewModel.lastSeenLocation?.coordinate.latitude ?? 0.00
let CPLongitude: Double = locationViewModel.lastSeenLocation?.coordinate.longitude ?? 0.00
GeometryReader { geometry in
VStack {
Text("Restaurants")
.padding()
List(venueDataViewModel.venuesListTen) { index in
NavigationLink(destination: RestaurantsDetailView(venue: index)) {
HStack {
VStack(alignment: .leading, spacing: 6) {
Text(index.name ?? "")
.font(.body)
.lineLimit(2)
Text(index.address ?? "")
.font(.subheadline)
.lineLimit(2)
}
}
}
Spacer()
if index.image != nil {
WebImage(url: URL(string: index.image ?? ""), options: .highPriority, context: nil)
.resizable()
.frame(width: 70, height: 70, alignment: .center)
.aspectRatio(contentMode: .fill)
.cornerRadius(12)
}
}
Text("Selected: \(selectedOption)")
Spacer()
}.toolbar {
ToolbarItem(placement: .navigationBarLeading) {
Button(action: {
showingSheet.toggle()
}, label: {
Image(systemName: "line.horizontal.3")
.imageScale(.large)
}
)
.sheet(isPresented: $showingSheet, content: {
NavigationView {
RestaurantsFilterView(selectedOption: self.$selectedOption)
}
})
}
}
.onAppear {
venueDataViewModel.retrieveVenues(latitude: CPLatitude, longitude: CPLongitude, category: "restaurants", limit: 50, sortBy: selectedOption, locale: "en_US") { (response, error) in
if let error = error {
print("\(error)")
}
}
}
}
}
}
Filter view:
import SwiftUI
struct RestaurantsFilterView: View {
#EnvironmentObject var locationViewModel: LocationViewModel
#EnvironmentObject var venueDataViewModel: VenueDataViewModel
var sortOptions = ["rating", "review_count"]
#Binding var selectedOption: String
var body: some View {
let CPLatitude: Double = locationViewModel.lastSeenLocation?.coordinate.latitude ?? 0.00
let CPLongitude: Double = locationViewModel.lastSeenLocation?.coordinate.longitude ?? 0.00
VStack {
Text("Filter")
Form {
Section {
Picker(selection: $selectedOption, label: Text("Sort")) {
ForEach(sortOptions, id: \.self) {
Text($0)
}
}.onChange(of: selectedOption) { Equatable in
venueDataViewModel.retrieveVenues(latitude: CPLatitude, longitude: CPLongitude, category: "restaurants", limit: 50, sortBy: selectedOption, locale: "en_US") { (response, error) in
if let error = error {
print("\(error)")
}
}
}
}
}
}
}
}
I am still new to Swift and SwiftUI so I appreciate the help.
Thank you!
this is a Macos app where the parsclass is setup in a previous view that contains the YardageRowView below. That previous view is responsible for changing the contents of the parsclass. This is working is other views that use a NavigationLink to display the views.
When the parsclass is changed, this view is refreshed, but the previous value is put in the text field on the holeValueTestView.
I cannot comprehend how the value is not being passed into the holeValueTestView correctly
This is a view shown as a .sheet, and if I dismiss it and display it again, everything is fine.
if you create a macOS project called YardageSample and replace the ContentView.swift and YardageSampleApp.swift with the two files below, you can see that the display in red changes and the black numbers do not change until you click Done and redisplay the .sheet
//
// YardageSampleApp.swift
// YardageSample
//
// Created by Brian Quick on 2021-04-12.
//
import SwiftUI
#main
struct YardageSampleApp: App {
#StateObject var parsclass = parsClass()
var body: some Scene {
WindowGroup {
ContentView()
.environmentObject(parsclass)
}
}
}
//
// ContentView.swift
// YardageSample
//
// Created by Brian Quick on 2021-04-12.
//
import SwiftUI
struct ContentView: View {
#StateObject var parsclass = parsClass()
enum ActiveSheet : String , Identifiable {
case CourseMaintenance
var id: String {
return self.rawValue
}
}
#State var activeSheet : ActiveSheet? = nil
var body: some View {
Button(action: {
self.activeSheet = .CourseMaintenance
}) {
Text("Course Maintenance")
}
.sheet(item: $activeSheet) { sheet in
switch sheet {
case .CourseMaintenance:
CourseMaintenance()
}
}.frame(width: 200, height: 200, alignment: /*#START_MENU_TOKEN#*/.center/*#END_MENU_TOKEN#*/)
}
}
class parsClass: ObservableObject {
#Published var pars = [parsRec]()
init() {
self.pars = [parsRec]()
self.pars.append(parsRec())
}
func create(newpars: [parsRec]) {
pars.removeAll()
pars = newpars
}
}
class parsRec: Identifiable, Codable {
var id = UUID()
var Hole = 1
var Yardage = 1
}
struct CourseMaintenance: View {
#EnvironmentObject var parsclass: parsClass
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack {
Button(action: {presentationMode.wrappedValue.dismiss()}, label: {
Text("Done")
})
Button(action: {switchScores(number: 1)}, label: {
Text("Button 1")
})
Button(action: {switchScores(number: 2)}, label: {
Text("Button 2")
})
Button(action: {switchScores(number: 3)}, label: {
Text("Button 3")
})
CourseDetail().environmentObject(parsclass)
}.frame(width: 400, height: 400, alignment: .center)
}
func switchScores(number: Int) {
var newparRecs = [parsRec]()
for i in 0..<17 {
let myrec = parsRec()
myrec.Hole = i
myrec.Yardage = number
newparRecs.append(myrec)
}
parsclass.create(newpars: newparRecs)
}
}
struct CourseDetail: View {
#EnvironmentObject var parsclass: parsClass
var body: some View {
HStack(spacing: 0) {
ForEach(parsclass.pars.indices, id: \.self) { indice in
// this displays the previous value
holeValueTestView(value: String(parsclass.pars[indice].Yardage))
// this displays the correct value after parsclass has changed
Text(String(parsclass.pars[indice].Yardage))
.foregroundColor(.red)
}
}
}
}
struct holeValueTestView: View {
#State var value: String
var body: some View {
//TextField(String(value), text: $value)
Text(value)
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
There are a couple of issues going on:
You have multiple instances of parsClass. One is defined in YardageSampleApp and passed into the view hierarchy as a #EnvironmentObject. The second is defined in ContentView as a #StateObject. Make sure you're only using one.
On holeValueTestView, you defined value as a #State variable. That gets set initially when the view is created by its parent and then it maintains its own state. So, when the environmentObject changed, because it was in charge of its own state at this point, it didn't update the value. You can simply remove #State and see the behavior that you want.
struct ContentView: View {
#EnvironmentObject var parsclass : parsClass //<-- Here
enum ActiveSheet : String , Identifiable {
case CourseMaintenance
var id: String {
return self.rawValue
}
}
#State var activeSheet : ActiveSheet? = nil
var body: some View {
Button(action: {
self.activeSheet = .CourseMaintenance
}) {
Text("Course Maintenance")
}
.sheet(item: $activeSheet) { sheet in
switch sheet {
case .CourseMaintenance:
CourseMaintenance()
}
}.frame(width: 200, height: 200, alignment: .center)
}
}
struct holeValueTestView: View {
var value: String //<-- Here
var body: some View {
Text(value)
}
}
As a side note:
In Swift, normally type names are capitalized. If you want to write idiomatic Swift, you would change your parsClass to ParsClass for example.
I am struggling to create an animation of a changing date value. A simplified example is below. It is intended to update the Text view with changing values as the date is updated from its original value to its new value. Help would be most appreciated!
struct DateAnimationView: View {
#State var date = Date()
typealias AnimatableData = Date
var animatableData: Date{
get{date}
set{date = newValue}
}
var body: some View {
VStack{
Text(date, style: .time)
.padding()
Button(action:{
withAnimation(.linear(duration: 3.0)){
date.addTimeInterval(60 * 60 * 3)
}
}){
Text("Add 3 hours")
}
.padding()
Spacer()
}
}
}
Another attempt which also fails:
struct InnerView: View {
var date: Date
var interval: TimeInterval
typealias AnimatableData = TimeInterval
var animatableData: TimeInterval{
get{interval}
set{interval = newValue}
}
var body: some View{
Text(date.addingTimeInterval(interval), style: .time)
}
}
struct DateAnimationView: View{
#State var isOn: Bool = false
var body: some View{
VStack{
InnerView(date: Date(), interval: isOn ? 60*60*3 : 0)
Button(action:{
isOn.toggle()
}){
Text("Go")
}
}
}
}
The essential idea is that you need to specify an id for the component you're animating. SwiftUI uses this id to understand if it's the same component or a new component when doing a redraw. If it is a new component, it will remove the old one and add a new with the animation. The code below achieves the animation.
struct DateAnimationView: View {
#State var date = Date()
typealias AnimatableData = Date
var animatableData: Date{
get{date}
set{date = newValue}
}
var body: some View {
VStack{
Text(date, style: .time)
.padding()
.id(String(date.hashValue))
Button(action:{
withAnimation(.linear(duration: 3.0)){
date.addTimeInterval(60 * 60 * 3)
}
}){
Text("Add 3 hours")
}
.padding()
Spacer()
}
}
}
A similar issue is solved by the solution posted here.
My full project is here https://github.com/m3rtkoksal/TaskManager
I have made SelectedTask an environment object as below
let context = persistentContainer.viewContext
let contentView = ContentView()
.environmentObject(observer())
.environmentObject(SelectedTask())
.environment(\.managedObjectContext,context)
In my TaskElement model I have created another class called SelectedTask as below
class SelectedTask: ObservableObject {
#Published var item = [TaskElement]()
func appendNewTask(task: TaskElement) {
objectWillChange.send()
item.append(TaskElement(title: task.title, dateFrom: task.dateFrom , dateTo: task.dateTo , text: task.text))
}
}
I am trying to fetch an item inside the scroll view and get its data to be able to modify it in the NewTaskView as below
struct ScrollViewTask: View {
#ObservedObject private var obser = observer()
#EnvironmentObject var selectedTask : SelectedTask
#State var shown: Bool = false
var body: some View {
ScrollView(.vertical) {
VStack {
ForEach(self.obser.tasks) { task in
TaskElementView(task:task)
.onTapGesture {
self.selectedTask.objectWillChange.send()
self.selectedTask.appendNewTask(task: task) //THREAD 1 ERROR
print(task)
self.shown.toggle()
}
}
}
}
.onAppear {
self.obser.fetchData()
}
.fullScreenCover(isPresented: $shown, content: {
NewTaskView(isShown: $shown)
.environmentObject(selectedTask)
})
}
}
But when I tap one of the items in scrollview I am getting a Thread 1 error #self.selectedTask.appendNewTask(task: task)
Thread 1: Fatal error: No ObservableObject of type SelectedTask found. A View.environmentObject(_:) for SelectedTask may be missing as an ancestor of this view.
If I change as ScrollViewTask().environmentObject(self.obser)
then this happens
This is how my TaskFrameView is called
import SwiftUI
struct TaskListView: View {
#State private(set) var data = ""
#State var isSettings: Bool = false
#State var isSaved: Bool = false
#State var shown: Bool = false
#State var selectedTask = TaskElement(title: "", dateFrom: "", dateTo: "", text: "")
var body: some View {
NavigationView {
ZStack {
Color(#colorLiteral(red: 0.9333333333, green: 0.9450980392, blue: 0.9882352941, alpha: 1)).edgesIgnoringSafeArea(.all)
VStack {
TopBar()
HStack {...}
CustomSegmentedView()
ZStack {
TaskFrameView() // scrollview inside
VStack {
Spacer()
HStack {...}
}
NavigationLink(
destination: NewTaskView(isShown: $shown).environmentObject(selectedTask),
isActive: $shown,
label: {
Text("")
})
}
}
}
.navigationBarHidden(true)
Spacer()
}
.navigationBarHidden(true)
}
}
It looks like the selectedTask is not injected to the TaskListView.
Find the place where you call TaskListView() and inject the selectedTask as an EnvironmentObject.
In ContentView:
struct ContentView: View {
#EnvironmentObject var selectedTask : SelectedTask
...
TaskListView().environmentObject(selectedTask)
Also don't create new instances of selectedTask like:
#State var selectedTask = TaskElement(title: "", dateFrom: "", dateTo: "", text: "")
Get the already created instance from the environment instead:
#EnvironmentObject var selectedTask: SelectedTask
call scroll view by sending the observer object as environment object modifier
ScrollViewTask().environmentObject(self. observer)