swift - Why doesn't my background image fill the entire screen consistently in SwiftUI? - Stack Overflow

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I'm a beginner learning SwiftUI, and I'm currently building a weather app. One of my challenges is getting my background image to fill the entire view properly. I want the image to act as a full-screen sky background, but when I run the app, the background image (sky) either doesn’t cover the whole screen or looks cropped in some cases.

I’ve already tried:

Using .resizable() and .scaledToFill() on the background image. Adding .ignoresSafeArea() to make the background cover the full screen. Ensuring that the TabView and other content have .frame(maxWidth: .infinity, maxHeight: .infinity) to fill the space.

I would appreciate a second eye and would love to learn from this experience. I did not expect an image to be something I would struggle with.

var body: some View {
    ZStack {
        // Background image
        Image("sky")
            .resizable()
            .scaledToFill()
            .ignoresSafeArea() // I expected this to make the image fill the entire screen
        
        VStack(spacing: 0) {
            // Header Section
            ZStack {
                Image("BG")
                    .resizable()
                    .scaledToFill()
                
                HStack(spacing: 10) {
                    Text("Change Location")
                        .font(.headline)
                        .foregroundColor(.black)
                    
                    TextField("Enter New Location", text: $weatherMapPlaceViewModel.newLocation)
                        .onSubmit {
                            Task {
                                await weatherMapPlaceViewModel.updateWeatherForLocation()
                                if let errorMessage = weatherMapPlaceViewModel.errorMessage {
                                    alertMessage = errorMessage
                                    showingAlert = true
                                }
                            }
                        }
                        .padding(8)
                        .background(Color.white)
                        .overlay(
                            RoundedRectangle(cornerRadius: 4)
                                .stroke(Color.gray, lineWidth: 1)
                        )
                        .frame(width: 200, height: 40)
                }
                .padding(.horizontal, 20)
                .padding(.top, 60)
            }
            .frame(height: 130)
            
            // Tab View Section
            TabView {
                CurrentWeatherView()
                    .tabItem { Label("Now", systemImage: "sun.max.fill") }
                
                ForecastWeatherView()
                    .tabItem { Label("5-Day Weather", systemImage: "calendar") }
                
                MapView()
                    .tabItem { Label("Place Map", systemImage: "map") }
                
                VisitedPlacesView()
                    .tabItem { Label("Stored Places", systemImage: "globe") }
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity) // Tried this to make sure the view uses all available space
            .background(Color.clear) // Ensures ZStack's background is visible
        }
        .onAppear {
            Task {
                await weatherMapPlaceViewModel.updateWeatherForLocation()
                if let errorMessage = weatherMapPlaceViewModel.errorMessage {
                    alertMessage = errorMessage
                    showingAlert = true
                }
            }
        }
        .alert(isPresented: $showingAlert) {
            Alert(
                title: Text("Notification"),
                message: Text(alertMessage),
                dismissButton: .default(Text("OK"))
            )
        }
    }
}

I’ve already tried:

• Using .resizable() and .scaledToFill() with .ignoresSafeArea() on the sky image to ensure it fills the screen.

• Adding .frame(maxWidth: .infinity, maxHeight: .infinity) to my VStack and TabView to ensure they don’t constrain the background.

• Debugging by removing all stacks, including the VStack, and noticed that when I removed the header image (BG), the sky background did fill the entire screen as expected.

I'm a beginner learning SwiftUI, and I'm currently building a weather app. One of my challenges is getting my background image to fill the entire view properly. I want the image to act as a full-screen sky background, but when I run the app, the background image (sky) either doesn’t cover the whole screen or looks cropped in some cases.

I’ve already tried:

Using .resizable() and .scaledToFill() on the background image. Adding .ignoresSafeArea() to make the background cover the full screen. Ensuring that the TabView and other content have .frame(maxWidth: .infinity, maxHeight: .infinity) to fill the space.

I would appreciate a second eye and would love to learn from this experience. I did not expect an image to be something I would struggle with.

var body: some View {
    ZStack {
        // Background image
        Image("sky")
            .resizable()
            .scaledToFill()
            .ignoresSafeArea() // I expected this to make the image fill the entire screen
        
        VStack(spacing: 0) {
            // Header Section
            ZStack {
                Image("BG")
                    .resizable()
                    .scaledToFill()
                
                HStack(spacing: 10) {
                    Text("Change Location")
                        .font(.headline)
                        .foregroundColor(.black)
                    
                    TextField("Enter New Location", text: $weatherMapPlaceViewModel.newLocation)
                        .onSubmit {
                            Task {
                                await weatherMapPlaceViewModel.updateWeatherForLocation()
                                if let errorMessage = weatherMapPlaceViewModel.errorMessage {
                                    alertMessage = errorMessage
                                    showingAlert = true
                                }
                            }
                        }
                        .padding(8)
                        .background(Color.white)
                        .overlay(
                            RoundedRectangle(cornerRadius: 4)
                                .stroke(Color.gray, lineWidth: 1)
                        )
                        .frame(width: 200, height: 40)
                }
                .padding(.horizontal, 20)
                .padding(.top, 60)
            }
            .frame(height: 130)
            
            // Tab View Section
            TabView {
                CurrentWeatherView()
                    .tabItem { Label("Now", systemImage: "sun.max.fill") }
                
                ForecastWeatherView()
                    .tabItem { Label("5-Day Weather", systemImage: "calendar") }
                
                MapView()
                    .tabItem { Label("Place Map", systemImage: "map") }
                
                VisitedPlacesView()
                    .tabItem { Label("Stored Places", systemImage: "globe") }
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity) // Tried this to make sure the view uses all available space
            .background(Color.clear) // Ensures ZStack's background is visible
        }
        .onAppear {
            Task {
                await weatherMapPlaceViewModel.updateWeatherForLocation()
                if let errorMessage = weatherMapPlaceViewModel.errorMessage {
                    alertMessage = errorMessage
                    showingAlert = true
                }
            }
        }
        .alert(isPresented: $showingAlert) {
            Alert(
                title: Text("Notification"),
                message: Text(alertMessage),
                dismissButton: .default(Text("OK"))
            )
        }
    }
}

I’ve already tried:

• Using .resizable() and .scaledToFill() with .ignoresSafeArea() on the sky image to ensure it fills the screen.

• Adding .frame(maxWidth: .infinity, maxHeight: .infinity) to my VStack and TabView to ensure they don’t constrain the background.

• Debugging by removing all stacks, including the VStack, and noticed that when I removed the header image (BG), the sky background did fill the entire screen as expected.

• swift
• image
• swiftui

Share Improve this question Follow asked Jan 9 at 4:36 Najmo MahamuudNajmo Mahamuud 111 silver badge New contributor Najmo Mahamuud is a new contributor to this site. Take care in asking for clarification, commenting, and answering. Check out our Code of Conduct. 1

• I recommend removing the view model object with onAppear/Task and simply using .task instead to call the async func and set the result on an @State. – malhal Commented 2 days ago

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1 Answer 1

Sorted by: Reset to default 1

The size of a ZStack is determined by the size of its contents. When you use .scaledtoFill on an image, the image will overflow the frame in either the horizontal or the vertical direction... unless of course, the aspect ratio of the image exactly matches the screen. If the image is a regular layer in the ZStack then it causes the ZStack to overflow too.

A better approach is to show the image as an overlay over a Color. Colors are greedy and consume as much space as possible, so this causes the ZStack to fill the screen. However, an overlay is constrained by the frame of the view it is applied to, so the image no longer causes the ZStack to overflow the screen dimensions.

If the view is used as the parent or child view of a navigation stack then it can also be a good idea to clip the image. This prevents the overflow from being seen during transitions.

ZStack {
    // Background image
    Color.clear
        .overlay {
            Image("sky")
                .resizable()
                .scaledToFill()
        }
        .clipped()
        .ignoresSafeArea()

    // ...
}

The same issue of overflow also exists for the image "BG", which is being shown in a nested ZStack. The same technique can also be used for resolving it, except that you may not want to ignore the safe area insets for this one:

ZStack {
    Color.clear
        .overlay {
            Image("BG")
                .resizable()
                .scaledToFill()
        }
        .clipped()
        // .ignoresSafeArea()

    // ...
}
.frame(height: 130)

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