I´m making a IOS app where I have a tabview. that tabview contains 3 different views, in one of these, i have a power button which has a growing animation, but when the view is changed, the power button back to off state. I´ll show you my code:
struct MainTabView: View {
@ObservedObject private var viewModel = MainTabViewModel()
var body: some View {
VStack {
HStack {
Text(viewModel.tabTitle).font(.largeTitle).bold().padding()
Spacer()
}
Spacer()
TabView(selection: $viewModel.selectedIndex) {
// view where is the button which activates the service
GPSButtonView()
.onTapGesture {
viewModel.selectedIndex = 0
}
.tabItem {
Image(systemName: "playpause")
}
.tag(0)
//view where is the map view
Text("Map")
.onTapGesture {
viewModel.selectedIndex = 1
}
.tabItem {
Image(systemName: "map")
}
.tag(1)
SettingsView()
.onTapGesture {
viewModel.selectedIndex = 2
}
.tabItem {
Image(systemName: "gear.circle")
}
.tag(2)
}
}
}
}
struct GPSButtonView: View {
@ObservedObject var viewModel = GPSButtonViewModel()
var body: some View {
VStack {
Button(
action: {
//button tapped
viewModel.gpsState.toggle()
viewModel.show.toggle()
}
) {
Image(systemName: "power.circle.fill")
.resizable()
.frame(width: 100, height: 100)
.foregroundColor(viewModel.gpsState ? .green : .red)
.scaleEffect(viewModel.show ? 2 : 1)
.animation(
Animation.easeInOut(duration: 0.5),
value: viewModel.show
)
}
}
}
}
class GPSButtonViewModel: ObservableObject {
//properties
@Published var gpsState = false
@Published var show = false
}
I´ll show you too a gif of the problem:
problem gif
2
Answers
You could conserve the state of the button by moving the ButtonViewModel up in the hierarchy.
Add this to your
MainTabView
:and when you call your view:
and important
remove the initializer from your buttonview:
You shouldn’t be using objects in SwiftUI like this, it’s best to use structs, e.g.
Then do