Hey!
Is there any opportunity in SwiftUI to keep a global variable that can changed its value and not cause views refresh (because I'm not going to display the value of this var)?
Aleksa_Khruleva
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Hi!
I'm learning SwiftUI and now got stuck with a problem of using @EnvironmentObject. The problem is: I get an email inputed by user and I have to pass it through several view (each view I call with NavigationLink). But I get an error sometimes:
struct RepeatPinView: View {
@State var pin: String
@State var pinRepeat: String = ""
@State var text: String = "Repeat PIN"
@State var selection: String? = nil
@EnvironmentObject var globalObj: GlobalObj
@Environment(\.colorScheme) var colorScheme
var body: some View {
let buttons: [[numPadButton]] = [
[.one, .two, .three],
[.four, .five, .six],
[.seven, .eight, .nine],
[.dop, .zero, .del],
]
VStack {
NavigationLink(destination: ContentView(), tag: "GotPin", selection: $selection) { EmptyView() }
Spacer()
// Text("Pin repeat \(globalObj.email)")
/* here I'm trying to check the email but sometimes and sometimes not (whaat.. can't understand how it works) I get a Fatal error: No ObservableObject of type GlobalObj found
*/
Text(text)
.font(.system(size: 30))
Spacer()
Text(pinRepeat)
.font(.system(size: 30))
.onChange(of: pinRepeat) { pinRepeat in
print(pinRepeat)
// print(globalObj.email)
/* same problem, sometimes get a Fatal error*/
if pinRepeat.count == 4 {
if self.pinRepeat == pin {
print(globalObj.email)
let textToWrite = globalObj.email + "\n" + pinRepeat
print(textToWrite)
/* surprisingly, but here everything works fine WHY??? */
selection = "GotPin"
} else {
text = "Try again"
}
}
}
.frame(width: 100, height: 50, alignment: .center)
Spacer()
ForEach(buttons, id: \.self) { row in
HStack {
ForEach(row, id: \.self) { item in
Button(action: {
switch item.rawValue {
case "dop":
print("dop")
case "del":
print("del")
if pinRepeat != "" {
pinRepeat.removeLast()
}
default:
pinRepeat.append(item.rawValue)
}
}, label: {
if item.rawValue == "del" {
Image(systemName: "delete.left")
.font(.title)
.foregroundColor(colorScheme == .dark ? .white : .black)
.padding()
} else if item.rawValue == "dop" {
Text("")
.font(.title)
.foregroundColor(colorScheme == .dark ? .white : .black)
.padding()
} else {
Text(item.rawValue)
.fontWeight(.bold)
.font(.largeTitle)
.foregroundColor(colorScheme == .dark ? .white : .black)
.padding()
.background(
Circle()
.stroke(Color.yellow, lineWidth: 4)
.frame(width: buttonWidth(item: item) - 5, height: buttonHeight(item: item) - 5, alignment: .center)
)
}
})
.frame(width: buttonWidth(item: item), height: buttonHeight(item: item), alignment: .center)
.padding([.trailing, .leading], 7)
}
}
.padding(.bottom, 7)
}
Spacer()
Spacer()
Spacer()
}
}
}
In previous views (there are three views before this one) I never got a Fatal error doing the same things.
Help me, please
Hey, everyone! Now I'm trying to do a simple app where I have a list of titles. I have two actions: tap the button "plus" to add new title and tap the row to edit the title. Each time I call "sheet". I use extra var to handle multiple sheets. So, I use "activeSheet" which changes when I tap the row and when I tap add button:
	@State var activeSheet = 0
@State var isPresented = false
@State var filmID: UUID = UUID()
var body: some View {
NavigationView {
List {
ForEach (modelData) { watch in
Row(film: watch)
.onTapGesture {
filmID = watch.id!
activeSheet = 1
isPresented = true
}
}
.sheet(isPresented: $isPresented) {
if (activeSheet == 1) {
DetailNotWatchedView(filmID: $filmID, isPresentedDetailView: $isPresented)
}
else if (activeSheet == 2) {
AddingNotWatchedView(isPresented: $isPresented)
}
}
.navigationBarTitle("To watch")
.navigationBarItems(trailing:
Button(action: {
activeSheet = 2
isPresented = true },
label: { Image(systemName: "plus.circle").imageScale(.large) }))
.listStyle(PlainListStyle())
}
The problem is that when I tap add button before tapping the row I go to DetailNotWatchedView instead of AddingNotWatchedView. I suppose when I tap add button activeSheet must change to 2. But if I tap the row before I tap the add button everything works OK. I can't understand how to fix it.
Hey, everyone! I've just started learning SwiftUI. Moreover, I upgraded Xcode yesterday so now it is Xcode 12.
My problem:
I need to make a list and locate it in NavigationView. Everything is OK until I'm trying to add NavigationBarItems. When I add NavigationBarItems the extra grey-colored space around list appears. Probably it is because of Xcode 12. Help me, please.
My code:
import SwiftUI
struct ContentView: View {
var body: some View {
let f1 = Film(id: UUID(), title: "Harry Potter", type: "film")
let f2 = Film(id: UUID(), title: "Who am I", type: "film")
let f3 = Film(id: UUID(), title: "Scorpion", type: "series")
let f4 = Film(id: UUID(), title: "Manifest", type: "series")
let films = [f1, f2, f3, f4]
NavigationView {
List (films) { watch in
Text(watch.title)
}
.navigationBarItems(trailing: EditButton())
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
struct Film: Identifiable {
var id: UUID
var title: String
var type: String
}