Is it possible to display images in SwiftUI `.alert`? - swiftui

Alert(title: <#T##Text#>, message: <#T##Text?#>, ...) inits take title and messages only as Text not a View. But Text is capable of displaying images. So why can't I display images as a title or a message?
Here is a small playground with an alert that tries to show an image as its title, but shows just some empty space. Although no errors appear.
import SwiftUI
import PlaygroundSupport
struct ContentView: View {
#State private var showAlert = false
var body: some View {
VStack {
Text(Image(systemName: "info.circle")) // Just to ensure `Text` can display `Image`
Button("Show Alert") {
self.showAlert = true
}
.alert(isPresented: $showAlert) {
Alert(title: Text(Image(systemName: "info.circle")),
message: Text("Alert message").bold() /* bold is not working */,
dismissButton: .default(Text("OK")))
}
}
.frame(width: 300, height: 600) // Sorry about it
}
}
PlaygroundPage.current.setLiveView(ContentView().previewDevice(PreviewDevice(stringLiteral: "iPhone 7")))
//`.previewdevice` has no effect in playground

Related

Back button messed with content on a detail view

I have items on a list. Every item is a NavigationLink that, once clicked, calls this:
import SwiftUI
struct ItemDetail: View {
private var item:MyItem
var body: some View {
ScrollView {
Text (item.fullDescription)
.fixedSize(horizontal: false, vertical: true)
.frame(alignment:.leading)
.padding([.leading, .trailing], 10)
}
}
Descriptions can be long. So, when I scroll the description up to read all content, the content gets over the back button, horribly, like this:
How do I solve that? Is there any way to make the navigation bar opaque?
I am unable to replicate this, but as long as you are using the correct navigation tree it should work as intended. Please see the code below for a simple example.
//
// ContentView.swift
// Tester
//
// Created by Jarren Campos on 3/15/22.
//
import SwiftUI
struct ContentView: View {
var body: some View{
NavigationView{
VStack{
NavigationLink(destination: ItemDetail()) {
Text("To new view")
}
}
}
}
}
struct ItemDetail: View {
var body: some View {
ScrollView {
Text ("slkdjf dksljf klsdj fklsdjf klsdj fklsdj fklsdjfklsd jfklsdj fklsdjfklsdjfkldjfkldjfkldjfkldjfkldjfkld jfkldjfkdljfkdlfjkdlfjkdfjdkfj kdjfkdjfkdjfkdjfkdjfdkjfkdfjdkfjdfjdkfj")
.fixedSize(horizontal: false, vertical: true)
.frame(alignment:.leading)
.padding([.leading, .trailing], 10)
}
}
}

SwiftUI changing navigation bar background color for inline navigationBarTitleDisplayMode

I just started coding in SwiftUI and came across a problem. I need to give different colors to the background of the navigation bar (NavigationView). The colors will change as I go from one view to the next. I need to have this working for navigationBarTitleDisplayMode being "inline".
I tried the solutions presented in:
SwiftUI update navigation bar title color
but none of these solutions work fully for what I need.
The solution in this reply to that post works for inline:
Using UIViewControllerRepresentable. Nevertheless, when we first open the view it will show the color of the previous view for one second, before changing to the new color. I would like to avoid this and have the color displayed as soon as everything appears on screen. Is there a way to do this?
This other solution will not work either: Changing UINavigation's appearance in init(), because when I set the background in init(), it will change the background of all the views in the app. Again, I need the views to have different background colors.
I tried something similar to this solution: Modifying Toolbar, but it does not allow me to change the color of the navigation bar.
The other solution I tried was this: Creating navigationBarColor function, which is based on: NAVIGATIONVIEW DYNAMIC BACKGROUND COLOR IN SWIFTUI. This solution works for navigationBarTitleDisplayMode "large", but when setting navigationBarTitleDisplayMode to "inline", it will show the background color of the navigation bar in a different color, as if it was covered by a gray/transparent layer. For example, the color it shows in "large" mode is:
Red color in large mode
But instead, it shows this color:
Red color in inline mode
Finally, I tried this solution: Subclassing UIViewController and configuring viewDidLayoutSubviews(), but it did not work for what I want it either.
The closest solutions for what I need are 1. and 4., but they still do not work 100%.
Would anybody know how to make any of these solutions work for navigationBarTitleDisplayMode inline, being able to change the background color of the navigation bar in different layouts, and showing the new color once the view is shown (without delays)?
Thank you!
By the way, I am using XCode 12.5.
Here is the sample code that I am using, taking example 4. as a model:
FirstView.swift
import SwiftUI
struct FirstView: View {
#State private var selection: String? = nil
var body: some View {
NavigationView {
GeometryReader { metrics in
VStack {
Text("This is the first view")
NavigationLink(destination: SecondView(), tag: "SecondView", selection: $selection) {
EmptyView()
}
Button(action: {
self.selection = "SecondView"
print("Go to second view")
}) {
Text("Go to second view")
}
}
}
}.navigationViewStyle(StackNavigationViewStyle())
}
}
struct FirstView_Previews: PreviewProvider {
static var previews: some View {
FirstView()
}
}
SecondView.swift
On this screen, if I use
.navigationBarTitleDisplayMode(.large)
the color will be displayed properly: Navigation bar with red color
But using
.navigationBarTitleDisplayMode(.inline)
there is a blur on it: Navigation bar with some sort of blur over red color
import SwiftUI
struct SecondView: View {
#State private var selection: String? = nil
var body: some View {
GeometryReader { metrics in
VStack {
Text("This is the second view")
NavigationLink(destination: ThirdView(), tag: "ThirdView", selection: $selection) {
EmptyView()
}
Button(action: {
self.selection = "ThirdView"
print("Go to third view")
}) {
Text("Go to third view")
}
}
}
.navigationBarColor(backgroundColor: Color.red, titleColor: .black)
.navigationBarTitleDisplayMode(.inline)
}
}
struct SecondView_Previews: PreviewProvider {
static var previews: some View {
SecondView()
}
}
ThirdView.swift
This view displays the color properly as it is using
.navigationBarTitleDisplayMode(.large)
But if changed to
.navigationBarTitleDisplayMode(.inline)
it will show the blur on top of the color as well.
import SwiftUI
struct ThirdView: View {
var body: some View {
GeometryReader { metrics in
Text("This is the third view")
}
.navigationBarColor(backgroundColor: Color.blue, titleColor: .black)
.navigationBarTitleDisplayMode(.large)
}
}
struct ThirdView_Previews: PreviewProvider {
static var previews: some View {
ThirdView()
}
}
NavigationBarModifierView.swift
import SwiftUI
struct NavigationBarModifier: ViewModifier {
var backgroundColor: UIColor?
var titleColor: UIColor?
init(backgroundColor: Color, titleColor: UIColor?) {
self.backgroundColor = UIColor(backgroundColor)
let coloredAppearance = UINavigationBarAppearance()
coloredAppearance.configureWithTransparentBackground()
coloredAppearance.backgroundColor = UIColor(backgroundColor)
coloredAppearance.titleTextAttributes = [.foregroundColor: titleColor ?? .white]
coloredAppearance.largeTitleTextAttributes = [.foregroundColor: titleColor ?? .white]
coloredAppearance.shadowColor = .clear
UINavigationBar.appearance().standardAppearance = coloredAppearance
UINavigationBar.appearance().compactAppearance = coloredAppearance
UINavigationBar.appearance().scrollEdgeAppearance = coloredAppearance
UINavigationBar.appearance().tintColor = titleColor
}
func body(content: Content) -> some View {
ZStack{
content
VStack {
GeometryReader { geometry in
Color(self.backgroundColor ?? .clear)
.frame(height: geometry.safeAreaInsets.top)
.edgesIgnoringSafeArea(.top)
Spacer()
}
}
}
}
}
extension View {
func navigationBarColor(backgroundColor: Color, titleColor: UIColor?) -> some View {
self.modifier(NavigationBarModifier(backgroundColor: backgroundColor, titleColor: titleColor))
}
}
NOTE TO THE MODERATORS: Please, do not delete this post. I know similar questions were asked before, but I need an answer to this in particular which was not addressed. Please read before deleting indiscriminately, I need this for work. Also, I cannot ask questions inline in each of those solutions because I do not have the minimum 50 points in stackoverflow required to write there.
I think I have what you want. It is VERY touchy... It is a hack, and not terribly robust, so take as is...
I got it to work by having your modifier return a clear NavBar, and then the solution from this answer works for you. I even added a ScrollView to ThirdView() to make sure that scrolling under didn't affect in. Also note, you lose all of the other built in effects of the bar like translucency, etc.
Edit: I went over the code. The .navigationViewStyle was in the wrong spot. It likes to be outside of the NavigaionView(), where everything else needs to be inside. Also, I removed the part of the code setting the bar color in FirstView() as it was redundant and ugly. I hadn't meant to leave that in there.
struct NavigationBarModifier: ViewModifier {
var backgroundColor: UIColor?
var titleColor: UIColor?
init(backgroundColor: Color, titleColor: UIColor?) {
self.backgroundColor = UIColor(backgroundColor)
let coloredAppearance = UINavigationBarAppearance()
coloredAppearance.configureWithTransparentBackground()
coloredAppearance.backgroundColor = .clear // The key is here. Change the actual bar to clear.
coloredAppearance.titleTextAttributes = [.foregroundColor: titleColor ?? .white]
coloredAppearance.largeTitleTextAttributes = [.foregroundColor: titleColor ?? .white]
coloredAppearance.shadowColor = .clear
UINavigationBar.appearance().standardAppearance = coloredAppearance
UINavigationBar.appearance().compactAppearance = coloredAppearance
UINavigationBar.appearance().scrollEdgeAppearance = coloredAppearance
UINavigationBar.appearance().tintColor = titleColor
}
func body(content: Content) -> some View {
ZStack{
content
VStack {
GeometryReader { geometry in
Color(self.backgroundColor ?? .clear)
.frame(height: geometry.safeAreaInsets.top)
.edgesIgnoringSafeArea(.top)
Spacer()
}
}
}
}
}
extension View {
func navigationBarColor(backgroundColor: Color, titleColor: UIColor?) -> some View {
self.modifier(NavigationBarModifier(backgroundColor: backgroundColor, titleColor: titleColor))
}
}
struct FirstView: View {
#State private var selection: String? = nil
var body: some View {
NavigationView {
GeometryReader { _ in
VStack {
Text("This is the first view")
NavigationLink(destination: SecondView(), tag: "SecondView", selection: $selection) {
EmptyView()
}
Button(action: {
self.selection = "SecondView"
print("Go to second view")
}) {
Text("Go to second view")
}
}
.navigationTitle("First")
.navigationBarTitleDisplayMode(.inline)
.navigationBarColor(backgroundColor: .red, titleColor: .black)
}
}
.navigationViewStyle(StackNavigationViewStyle())
}
}
struct SecondView: View {
#State private var selection: String? = nil
var body: some View {
VStack {
Text("This is the second view")
NavigationLink(destination: ThirdView(), tag: "ThirdView", selection: $selection) {
EmptyView()
}
Button(action: {
self.selection = "ThirdView"
print("Go to third view")
}) {
Text("Go to third view")
}
}
.navigationTitle("Second")
.navigationBarTitleDisplayMode(.inline)
.navigationBarColor(backgroundColor: .blue, titleColor: .black)
}
}
struct ThirdView: View {
var body: some View {
ScrollView {
ForEach(0..<50) { _ in
Text("This is the third view")
}
}
.navigationTitle("Third")
.navigationBarTitleDisplayMode(.inline)
.navigationBarColor(backgroundColor: .green, titleColor: .black)
}
}
iOS 16
Since this version of SwiftUI, there is a dedicated modifier for setting any toolbar background color (including the navigation bar):
Xcode 14 beta 5 (Not working 🤦🏻‍♂️, waiting for beta 6...)
.toolbarBackground(.red, for: .navigationBar)
Xcode 14 beta 1,2,3,4
.toolbarBackground(.red, in: .navigationBar)
It works perfectly in in inline mode and also animates between modes.
For my custom view the following code worked well.
struct HomeView: View {
init() {
//Use this if NavigationBarTitle is with Large Font
UINavigationBar.appearance().largeTitleTextAttributes = [.foregroundColor: UIColor.systemIndigo]
//Use this if NavigationBarTitle is with displayMode = .inline
UINavigationBar.appearance().titleTextAttributes = [.foregroundColor: UIColor.systemIndigo]
UINavigationBar.appearance().backgroundColor = UIColor.clear
UINavigationBar.appearance().barTintColor = UIColor(Color(red: 32 / 255, green: 72 / 255, blue: 63 / 255))
}
var body: some View {
NavigationView {
ZStack {
...
...
...
}
.padding(.zero)
.navigationTitle("Feedbacks")
}
}
}
and result is like that:
Here is a bit hacky solution, but it works for me (as of iOS 15) both for .large and .inline display modes.
import SwiftUI
enum Kind: String, CaseIterable {
case checking
case savings
case investment
}
struct PaddedList: View {
#Binding var name: String
#Binding var kind: Kind
var body: some View {
NavigationView {
List {
TextField("Account name", text: $name)
Picker("Kind", selection: $kind) {
ForEach(Kind.allCases, id: \.self) { kind in
Text(kind.rawValue).tag(kind)
}
}
.listRowSeparatorTint(.red)
Spacer()
}
.padding(.top, 1) // note top 1 padding!
.background(.green) // the color "bleeds" through
.navigationBarTitle("Navigation Bar")
}
}
}
struct PaddedList_Previews: PreviewProvider {
static var previews: some View {
PaddedList(name: .constant(""), kind: .constant(.checking))
}
}

SwiftUI .fullScreenCover appears as a .sheet

I expected to be able to dismiss a sheet and present a fullScreenCover straight after, however this doesn't seem to work without a delay between the two state modifications.
struct ContentView: View {
#State var sheet = false
#State var cover = false
var body: some View {
Button("Click me for sheet") {
sheet = true
}
.fullScreenCover(isPresented: $cover) {
Text("This is a full screen cover")
}
.sheet(isPresented: $sheet) {
Text("This is a sheet")
Button("This doesn't work") {
sheet = false
cover = true
}
Button("This works") {
sheet = false
DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
cover = true
}
}
}
}
}
Clicking the "This doesn't work" button produces the below image demonstrating a fullScreen cover displaying as a sheet and not covering the entire screen:
Introducing a small delay between the two state modifications which is done by clicking the "This works" button fixes the issue.
What am I not understanding about SwiftUI here that would explain this behaviour?
Tested on:
Xcode 12.5.1
iPhone 12 Pro Max Simulator running iOS 14.5
Adding the modifiers to seperate view like this also doesn't work:
Text("Another view").sheet(isPresented: $sheet) { ...
you could try this:
struct ContentView: View {
#State var sheet = false
#State var cover = false
var body: some View {
Button("Click me for sheet") {
sheet = true
}
.fullScreenCover(isPresented: $cover) {
Text("This is a full screen cover")
}
.sheet(isPresented: $sheet, onDismiss: {cover = true}) {
Text("This is a sheet")
}
}
}

SWIFTUI Button or NavigationLink?

I have a button called "save" that saves the user inputs.
But, I want to make it like, if the user tap on Button "Save", then the screen automatically goes back to the previous view. Can I do that by just adding a code to an action in Button? or do I have to use NavigationLink instead of Button?
Button(action: {
let title = shortcutTitle
currentShortcutTitle = title
UserDefaults.standard.set(title, forKey: "title")
}, label: {
Text("Save")
.padding()
.frame(width: 120, height: 80)
.border(Color.black)
}) //: Button - save
If you're just trying to go back to the previous view and already inside a NavigationView stack, you can use #Environment(\.presentationMode):
struct ContentView: View {
var body: some View {
NavigationView {
NavigationLink(destination: Screen2()) {
Text("Go to screen 2")
}
}.navigationViewStyle(StackNavigationViewStyle())
}
}
struct Screen2 : View {
#Environment(\.presentationMode) var presentationMode //<-- Here
var body: some View {
Button("Dismiss") {
presentationMode.wrappedValue.dismiss() //<-- Here
}
}
}

SwiftUI Alert How do I get it to work in a simple if statement?

This should be simple but I am hoping to display an alert when a condition is true.(see below) I have seen lots where you used a button to trigger an alert, but I just want an alert to trigger when a condition is met such as in a simple "If" statement. Which should appear as soon as the code is loaded.
import SwiftUI
struct ContentView: View {
#State private var showingAlert = false
var score = 3
var body: some View {
VStack{
if score == 3 {
showingAlert = true
} .alert(isPresented: $showingAlert) {
Alert(title: Text("Hello SwiftUI!"), message: Text("This is some detail message"), dismissButton: .default(Text("OK")))
}
}
}
You can check if your condition is true in the init() method of the view and then set the initial value of your showingAlert.
struct ContentView: View {
#State private var showingAlert = false
var score = 3
init()
{
//check if condition is true
if (true)
{
self._showingAlert = State(initialValue: true)
}
}
var body: some View {
VStack{
EmptyView()
} .alert(isPresented: self.$showingAlert) {
Alert(title: Text("Hello SwiftUI!"), message: Text("This is some detail message"), dismissButton: .default(Text("OK")))
}
}
}