Properly disable touch on UIPageControl in a TabView with PageTabViewStyle - swiftui

I have set up a (paging) TabView with .tabViewStyle(PageTabViewStyle(indexDisplayMode: .always)).
I would like the IndexView to be merely visual, i.e. no to respond to any touch.
To achieve this I have set UIPageControl.appearance().isUserInteractionEnabled = false, which in fact disables paging by touch.
However touches on the UIPageControl (highlighted in blue by setting its backgroundColor) are not passed to the List below: tapping on the blue area will not select the row in the List underneath.
Is there a way to achieve this?
Here is my sample code (running on iOS 14.0 beta 4):
struct ContentView: View {
init() {
UIPageControl.appearance().backgroundColor = UIColor(red: 0, green: 0, blue: 0.5, alpha: 0.5)
UIPageControl.appearance().isUserInteractionEnabled = false
}
var body: some View {
NavigationView {
TabView {
ForEach (0..<3, id: \.self) { page in
List {
ForEach (0..<30, id: \.self) { row in
NavigationLink(
destination: Text("Page \(page) Row \(row)"),
label: {
Text("Page \(page) Row \(row)")
})
}
}
.tag(page)
}
}
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .always))
.indexViewStyle(PageIndexViewStyle(backgroundDisplayMode: .always))
.navigationBarTitle("Title", displayMode: .inline)
.edgesIgnoringSafeArea(.bottom)
}
}
}

Related

TabView Label doesn't appear while the background color doesn't fill the entire screen

This is my reproducible code.
Problems: There is no error in my code but I can't find my TabView Label. The background was declared with .ignoresSafeArea(.all) but still doesn't fill the entire screen.
import SwiftUI
struct LibraryView: View {
var allColors: [Color] = [Color.red, Color.green, Color.blue]
var body: some View {
TabView {
ForEach(allColors, id: \.self) { color in
BookSubView(bColor: color)
.tabItem {
Text("BOOK")
.foregroundColor(color)
Image(systemName: "book")
}
}
}
.tabViewStyle(.page)
}
}
struct BookSubView: View {
var bColor: Color
var body: some View {
LinearGradient(colors: [bColor, Color.white], startPoint: .top,
endPoint: .bottom).ignoresSafeArea(.all)
}
}
Use a Label inside of the .tabItem modifier
BookSubView(bColor: color)
.tabItem {
// There are probably modifiers for Label you can use to customize to your needs
Label("Book", systemImage: "book")
}

How to recreate the grid (in screenshot) in SwiftUI without breaking navigation?

I am trying to recreate a layout similar to the Reminders app. Looking at it makes me think it was built with SwiftUI. I also believe Apple mentioned so in one of the WWDC videos (can't remember which one).
This above screenshot seems to be a List, with a LazyVGrid as the first View inside the List. Tapping on each of the items in the LazyVGrid, such as Today, Scheduled, All and Flagged, navigates to the relevant screen, which means they are all NavigationLinks. Also note that the LazyVGrid has 2 columns.
And then there is another section "My Lists" which has rows which look like regular list rows in a List with style .insetGrouped. Also, every item in this Section is a NavigationItem, and thus comes with the disclosure indicator on the right as usual. Recreating this is trivial, so it has been left out from the MRE.
I am having trouble recreating the first section, which has that LazyVGrid. I faced 3 problems (as mentioned in the image), of which I have been able to solve the first one only. The other two problems remain. I want to know if this MRE can be fixed, or is my entire approach incorrect.
I am including a minimum reproducible example below.
import SwiftUI
#main
struct TestApp: App {
var body: some Scene {
WindowGroup {
RemindersView()
}
}
}
struct RemindersView: View {
private var columns: [GridItem] = [GridItem(.adaptive(minimum: 150))]
private var smartLists: [SmartList] = SmartList.sampleLists
var body: some View {
NavigationView {
List {
Section(header: Text("Using LazyVGrid")) {
grid
}
Section(header: Text("Using HStack")) {
hstack
}
}
.navigationTitle("Store")
}
.preferredColorScheme(.dark)
}
private var grid: some View {
LazyVGrid(columns: columns, spacing: 8) {
ForEach(smartLists) { smartList in
// This use of **ZStack with an EmptyView with opacity 0** is a hack being used to avoid the disclosure indicator on each item in the grid
ZStack(alignment: .leading) {
NavigationLink( destination: SmartListView(list: smartList)) {
EmptyView()
}
.opacity(0)
SmartListView(list: smartList)
}
}
}
.listRowInsets(EdgeInsets())
.listRowBackground(Color.clear)
}
private var hstack: some View {
ScrollView(.horizontal) {
HStack {
ForEach(smartLists) { smartList in
NavigationLink(destination: SmartListView(list: smartList)) {
SmartListView(list: smartList)
}
.buttonStyle(.plain)
}
}
}
.listRowInsets(EdgeInsets())
.listRowBackground(Color.clear)
}
}
struct RemindersView_Previews: PreviewProvider {
static var previews: some View {
RemindersView()
}
}
struct SmartList: Identifiable {
var id: UUID = UUID()
var title: String
var count: Int
var icon: String
var iconColor: Color
static var sampleLists: [SmartList] {
let today = SmartList(title: "Today", count: 5, icon: "20.circle.fill", iconColor: .blue)
let scheduled = SmartList(title: "Scheduled", count: 12, icon: "calendar.circle.fill", iconColor: .red)
let all = SmartList(title: "All", count: 77, icon: "tray.circle.fill", iconColor: .gray)
let flagged = SmartList(title: "Flagged", count: 5, icon: "flag.circle.fill", iconColor: .orange)
return [today, scheduled, all, flagged]
}
}
struct SmartListView: View {
var list: SmartList
var body: some View {
VStack(alignment: .leading, spacing: 8) {
HStack(alignment: .center) {
Image(systemName: list.icon)
.renderingMode(.original)
.font(.title)
.foregroundColor(list.iconColor)
Spacer()
Text("\(list.count)")
.font(.system(.title, design: .rounded))
.fontWeight(.bold)
.padding(.horizontal, 8)
}
Text(list.title)
.font(.system(.headline, design: .rounded))
.foregroundColor(.secondary)
}
.padding(8)
.background(
RoundedRectangle(cornerRadius: 12)
.foregroundColor(.gray.opacity(0.25))
)
.padding(2)
.frame(minWidth: 150)
}
}
EDIT 1: Adding video demo of what editing the dynamic Grid looks like and how the Grid has dynamic grid items (via the Edit button at the top right): https://imgur.com/a/TV0kifY

SwiftUI: Custom label in navigation link is greyed out

I'm trying to use my custom card view as label to navigation link. this navigation link is also a Grid item.
The result is a
My Card Code:
struct CityCard: View {
var cityData: CityData
var body: some View {
VStack {
Text("\(cityData.name)")
.padding([.top], 10)
Spacer()
Image(systemName: cityData.forecastIcon)
.resizable()
.frame(width: 45, height: 45)
Spacer()
HStack(alignment: .bottom) {
Text(String(format: "%.2f $", cityData.rate))
.padding([.leading, .bottom], 10)
Spacer()
Text(String(format: "%.2f °", cityData.degrees))
.padding([.trailing, .bottom], 10)
}
}.frame(width: 150, height: 150)
.background(Color.blue)
.cornerRadius(10)
.navigationTitle(cityData.name)
}
}
My List View:
struct CityList: View {
var cities: [CityData]
let columns = [
GridItem(.flexible(minimum: 150, maximum: 150)),
GridItem(.flexible(minimum: 150, maximum: 150))
]
var body: some View {
ScrollView {
LazyVGrid(columns: columns, spacing: 20) {
ForEach(self.cities) { item in
NavigationLink(destination: Text(item.name), label: {
CityCard(cityData: item)
})
}
}
}
}
}
someone has a solution why it gives me this opacity?
Update:
The main contact view is:
It's greyed out because you don't yet have a NavigationView in your view hierarchy, which makes it possible to actually navigate to a new view.
You can, for example, wrap your ScrollView in a NavigationView:
var body: some View {
NavigationView {
ScrollView {
LazyVGrid(columns: columns, spacing: 20) {
ForEach(self.cities) { item in
NavigationLink(destination: Text(item.name), label: {
CityCard(cityData: item)
})
}
}
}
}
}
Or, if it's only happening in your preview, add a NavigationView to your preview code:
NavigationView {
CityList(...)
}
Keep in mind that if you have the default accent color (blue, in light mode) that your links will become invisible (since they will be blue) on top of the blue background. You can set a custom accent color in your project or via the accentColor modifier:
NavigationView {
//content
}.accentColor(.black)

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))
}
}

Using ScrollViewReader in SwiftUI how can I highlight the row I have scrolled to?

If I create this simple ScrollView containing 100 rows and create a button to scroll to row 60, I would like to highlight that I am at row 60, maybe with a background colour or similar. I cannot figure out how to do this.
var body: some View {
ScrollView {
ScrollViewReader { value in
Button("Jump to #60") {
value.scrollTo(60, anchor: .center)
}
ForEach(0..<100) { i in
Text("Line \(i)")
}
}
}
}
Here is possible approach - you introduce state for highlighted row, which can modify by needs, including for scroll to
Tested with Xcode 12b5 / iOS 14
#State private var highlighted: Int?
var body: some View {
ScrollView {
ScrollViewReader { value in
Button("Jump to #60") {
value.scrollTo(60, anchor: .center)
highlighted = 60
}
ForEach(0..<100) { i in
Text("Line \(i)")
.frame(maxWidth: .infinity)
.background(i == highlighted ? Color.gray : Color.clear)
}
}
}
}
Found a way.
Create a function to set a colour if the current index and the scrollTo target are equal.
func highlight(index: Int, target: Int) -> Color {
if target == index {
return .black
} else {
return .clear
}
Then use it to set background, border etc.
Text("Line \(i)")
.border(highlight(index: i, target: 60), width: 5)