Unwanted top padding on Swift TabView - ios

I have an issue which I cannot resolve. I have a TabView inside NavigationView with two tabs. Both tabs are constructed in the same way SearchBar + List, only difference is content, but issue appears even if I try to display the same content on both.
Issue is that on first tab there is extra padding between search bar and list, it does not appear on second tab. If I switch order in code issue is the same padding only on first tab (old second tab).
Important remark, it only happens with .listStyle(SidebarListStyle()) with .listStyle(PlainListStyle()) there is no extra padding, but then I cannot expand and colapse categories.
Code:
var body: some View {
NavigationView {
TabView {
ProductList()
.tabItem {
Label("Produkty", systemImage: "bag.circle.fill")
}
.onAppear {
self.title = "Produkty"
}
RecipeList()
.tabItem {
Label("Przepisy", systemImage: "book.circle.fill")
}
.onAppear {
self.title = "Przepisy"
}
}
.accentColor(.white)
.navigationBarTitle(title, displayMode: .inline)
}
}
Code for the ProductList():
import SwiftUI
struct ProductList: View {
#Environment(\.presentationMode) var presentationMode
#State private var searchText = ""
let categories: [String] = ["A", "B", "C"]
var body: some View {
VStack() {
SearchBar(text: $searchText)
.padding(.top, 10)
List(){
ForEach(categories, id: \.self) { cat in
Section(
header: Text(cat)
.fontWeight(.bold)
.foregroundColor(.gray)
){
ForEach(productData.filter{
searchText.isEmpty && $0.category.rawValue == cat ? true : $0.name.localizedCaseInsensitiveContains(searchText) && $0.category.rawValue == cat
}) { product in
NavigationLink(destination: ProductDetail(product: product)){
ProductRow(
product: product,
color: colorRank(value: product.rank[0].rawValue)
)
}
}
}
.accentColor(.gray)
}
}
.resignKeyboardOnDragGesture()
.listStyle(SidebarListStyle())
}.background(Color(UIColor.secondarySystemBackground).ignoresSafeArea())
}
}

Related

Presenting a modal view sheet from a Sub view

I am trying to present a sheet from a sub view selected from the menu item on the navigation bar but the modal Sheet does does not display. I spent a few days trying to debug but could not pin point the problem.
I am sorry, this is a little confusing and will show a simplified version of the code to reproduce. But in a nutshell, the problem seems to be a sheet view that I have as part of the main view. Removing the sheet code from the main view displays the sheet from the sub view. Unfortunately, I don't have the freedom to change the Mainview.swift
Let me show some code to make it easy to understand....
First, before showing the code, the steps to repeat the problem:
click on the circle with 3 dots in the navigation bar
select the second item (Subview)
click on the "Edit Parameters" button and the EditParameters() view will not display
ContentView.swift (just calls the Mainview()). Included code to copy for reproducing issue :-)
struct ContentView: View {
var body: some View {
NavigationView {
VStack {
Mainview()
}
}
}
}
Mainview.swift. This is a simplified version of the actual App which is quite complex and I don't have leeway to change much here unfortunately!
fileprivate enum CurrentView {
case summary, sub
}
enum OptionSheet: Identifiable {
var id: Self {self}
case add
}
struct Mainview: View {
#State private var currentView: CurrentView? = .summary
#State private var showSheet: OptionSheet? = nil
var body: some View {
GeometryReader { g in
content.frame(width: g.size.width, height: g.size.height)
.navigationBarTitle("Main", displayMode: .inline)
}
//Removing the below sheet view will display the sheet from the subview but with this sheet here, it the sheet from subview does not work. This is required as these action items are accessed from the second menu item (circle and arrow) navigation baritem
.sheet(item: $showSheet, content: { mode in
sheetContent(for: mode)
})
.toolbar {
HStack {
trailingBarItems
actionItems
}
}
}
var actionItems: some View {
Menu {
Button(action: {
showSheet = .add
}) {
Label("Add Elements", systemImage: "plus")
}
} label: {
Image(systemName: "cursorarrow.click").resizable()
}
}
var trailingBarItems: some View {
Menu {
Button(action: {currentView = .summary}) {
Label("Summary", systemImage: "list.bullet.rectangle")
}
Button(action: {currentView = .sub}) {
Label("Subview", systemImage: "circle")
}
} label: {
Image(systemName: "ellipsis.circle").resizable()
}
}
#ViewBuilder
func sheetContent(for mode: OptionSheet) -> some View {
switch mode {
case .add:
AddElements()
}
}
#ViewBuilder
var content: some View {
if let currentView = currentView {
switch currentView {
case .summary:
SummaryView()
case .sub:
SubView()
}
}
}
}
Subview.swift. This is the file that contains the button "Edit Parameters" which does not display the sheet. I am trying to display the sheet from this view.
struct SubView: View {
#State private var editParameters: Bool = false
var body: some View {
VStack {
Button(action: {
editParameters.toggle()
}, label: {
HStack {
Image(systemName: "square.and.pencil")
.font(.headline)
Text("Edit Parameters")
.fontWeight(.semibold)
.font(.headline)
}
})
.padding(10)
.foregroundColor(Color.white)
.background(Color(.systemBlue))
.cornerRadius(20)
.sheet(isPresented: $editParameters, content: {
EditParameterView()
})
.padding()
Text("Subview....")
}
.padding()
}
}
EditParameters.swift. This is the view it should display when the Edit Parameters button is pressed
struct EditParameterView: View {
var body: some View {
Text("Edit Parameters...")
}
}
Summaryview.swift. Nothing special here. just including for completeness
struct SummaryView: View {
var body: some View {
Text("Summary View")
}
}
In SwiftUI, you can't have 2 .sheet() modifiers on the same hierarchy. Here, the first .sheet() modifier is on one of the parent views to the second .sheet(). The easy solution is to move one of the .sheets() so it's own hierarchy.
You could either use ZStacks:
var body: some View {
ZStack {
GeometryReader { g in
content.frame(width: g.size.width, height: g.size.height)
.navigationBarTitle("Main", displayMode: .inline)
}
ZStack{ }
.sheet(item: $showSheet, content: { mode in
sheetContent(for: mode)
})
}
.toolbar {
HStack {
trailingBarItems
actionItems
}
}
}
or more elegantly:
var body: some View {
GeometryReader { g in
content.frame(width: g.size.width, height: g.size.height)
.navigationBarTitle("Main", displayMode: .inline)
}
.background(
ZStack{ }
.sheet(item: $showSheet, content: { mode in
sheetContent(for: mode)
})
)
.toolbar {
HStack {
trailingBarItems
actionItems
}
}
}

replace Tabbar with toolbar in SwiiftUI 2.0

I'm trying replicate the behavior of iOS Photos app.
Till now the thing I can't figure how could be done is the select mode, where when I press the button select how I can change the bottom bar?
Graphically, what I intend is, in this view:
When I pressed the button, the bottom bar changes to:
In the real project the views are embed inside a NavigationView
The code of the main view is similar to
struct ContentView: View {
var body: some View {
NavigationView{
TabView{
data()
.tabItem {
Text("Data")
}
data2()
.tabItem {
Text("Data")
}
}
}
}
I'm using Xcode 12 and swiftUI 2.0
First we need Conditional modifier like that https://stackoverflow.com/a/61253769/2715636
struct conditionalModifier: ViewModifier {
var isShowing: Bool
func body(content: Content) -> some View {
Group {
if self.isShowing {
content
.toolbar {
ToolbarItem(placement: .bottomBar, content: {
Button(action: {
}){
Image(systemName: "square.and.arrow.up")
}
})
}
.toolbar {
ToolbarItem(placement: .status, content: {
Text("Toolbar")
.fontWeight(.bold)
})
}
}
}
}}
I don't need else statement cause I only want to see Toolbar
else { content }
And here is my Tabbar inside ZStack. We're gonna overlay it with Text using Conditional modifier applied to Text
struct ContentView: View {
#State private var showToolbar: Bool = false
var body: some View {
Button(action: {
showToolbar.toggle()
}, label: {
Text(showToolbar ? "Show Tabbar" : "Show Toolbar")
}).padding()
ZStack {
TabView {
someView()
.tabItem {
Image(systemName: "placeholdertext.fill")
Text("Tab 1")
}
someView()
.tabItem {
Image(systemName: "placeholdertext.fill")
Text("Tab ")
}
someView()
.tabItem {
Image(systemName: "placeholdertext.fill")
Text("Tab 3")
}
}
Text("")
.modifier(conditionalModifier(isShowing: showToolbar))
}
}}
Final result
tabbar to toolbar
There's a new view modifier in iOS 16 that let you switch the tab bar and the bottom bar.
https://developer.apple.com/documentation/swiftui/view/toolbar(_:for:)
For example,
ContentView()
.toolbar(isSelecting ? .visible : .hidden, for: .bottomBar)
.toolbar(isSelecting ? .hidden : .visible, for: .tabBar)

SwiftUI Hide TabView bar inside NavigationLink views

I have a TabView and separate NavigationView stacks for every Tab item. It works well but when I open any NavigationLink the TabView bar is still displayed. I'd like it to disappear whenever I click on any NavigationLink.
struct MainView: View {
#State private var tabSelection = 0
var body: some View {
TabView(selection: $tabSelection) {
FirstView()
.tabItem {
Text("1")
}
.tag(0)
SecondView()
.tabItem {
Text("2")
}
.tag(1)
}
}
}
struct FirstView: View {
var body: some View {
NavigationView {
NavigationLink(destination: FirstChildView()) { // How can I open FirstViewChild with the TabView bar hidden?
Text("Go to...")
}
.navigationBarTitle("FirstTitle", displayMode: .inline)
}
}
}
I found a solution to put a TabView inside a NavigationView, so then after I click on a NavigationLink the TabView bar is hidden. But this messes up NavigationBarTitles for Tab items.
struct MainView: View {
#State private var tabSelection = 0
var body: some View {
NavigationView {
TabView(selection: $tabSelection) {
...
}
}
}
}
struct FirstView: View {
var body: some View {
NavigationView {
NavigationLink(destination: FirstChildView()) {
Text("Go to...")
}
.navigationBarTitle("FirstTitle", displayMode: .inline) // This will not work now
}
}
}
With this solution the only way to have different NavigationTabBars per TabView item, is to use nested NavigationViews. Maybe there is a way to implement nested NavigationViews correctly? (As far as I know there should be only one NavigationView in Navigation hierarchy).
How can I hide TabView bar inside NavigationLink views correctly in SwiftUI?
I really enjoyed the solutions posted above, but I don't like the fact that the TabBar is not hiding according to the view transition.
In practice, when you swipe left to navigate back when using tabBar.isHidden, the result is not acceptable.
I decided to give up the native SwiftUI TabView and code my own.
The result is more beautiful in the UI:
Here is the code used to reach this result:
First, define some views:
struct FirstView: View {
var body: some View {
NavigationView {
VStack {
Text("First View")
.font(.headline)
}
.navigationTitle("First title")
.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
.background(Color.yellow)
}
}
}
struct SecondView: View {
var body: some View {
VStack {
NavigationLink(destination: ThirdView()) {
Text("Second View, tap to navigate")
.font(.headline)
}
}
.navigationTitle("Second title")
.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
.background(Color.orange)
}
}
struct ThirdView: View {
var body: some View {
VStack {
Text("Third View with tabBar hidden")
.font(.headline)
}
.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
.background(Color.red.edgesIgnoringSafeArea(.bottom))
}
}
Then, create the TabBarView (which will be the root view used in your app):
struct TabBarView: View {
enum Tab: Int {
case first, second
}
#State private var selectedTab = Tab.first
var body: some View {
VStack(spacing: 0) {
ZStack {
if selectedTab == .first {
FirstView()
}
else if selectedTab == .second {
NavigationView {
VStack(spacing: 0) {
SecondView()
tabBarView
}
}
}
}
.animation(nil)
if selectedTab != .second {
tabBarView
}
}
}
var tabBarView: some View {
VStack(spacing: 0) {
Divider()
HStack(spacing: 20) {
tabBarItem(.first, title: "First", icon: "hare", selectedIcon: "hare.fill")
tabBarItem(.second, title: "Second", icon: "tortoise", selectedIcon: "tortoise.fill")
}
.padding(.top, 8)
}
.frame(height: 50)
.background(Color.white.edgesIgnoringSafeArea(.all))
}
func tabBarItem(_ tab: Tab, title: String, icon: String, selectedIcon: String) -> some View {
ZStack(alignment: .topTrailing) {
VStack(spacing: 3) {
VStack {
Image(systemName: (selectedTab == tab ? selectedIcon : icon))
.font(.system(size: 24))
.foregroundColor(selectedTab == tab ? .primary : .black)
}
.frame(width: 55, height: 28)
Text(title)
.font(.system(size: 11))
.foregroundColor(selectedTab == tab ? .primary : .black)
}
}
.frame(width: 65, height: 42)
.onTapGesture {
selectedTab = tab
}
}
}
This solution also allows a lot of customization in the TabBar.
You can add some notifications badges, for example.
If we talk about standard TabView, the possible workaround solution can be based on TabBarAccessor from my answer on Programmatically detect Tab Bar or TabView height in SwiftUI
Here is a required modification in tab item holding NavigationView. Tested with Xcode 11.4 / iOS 13.4
struct FirstTabView: View {
#State private var tabBar: UITabBar! = nil
var body: some View {
NavigationView {
NavigationLink(destination:
FirstChildView()
.onAppear { self.tabBar.isHidden = true } // !!
.onDisappear { self.tabBar.isHidden = false } // !!
) {
Text("Go to...")
}
.navigationBarTitle("FirstTitle", displayMode: .inline)
}
.background(TabBarAccessor { tabbar in // << here !!
self.tabBar = tabbar
})
}
}
Note: or course if FirstTabView should be reusable and can be instantiated standalone, then tabBar property inside should be made optional and handle ansbsent tabBar explicitly.
Thanks to another Asperi's answer I was able to find a solution which does not break animations and looks natural.
struct ContentView: View {
#State private var tabSelection = 1
var body: some View {
NavigationView {
TabView(selection: $tabSelection) {
FirstView()
.tabItem {
Text("1")
}
.tag(1)
SecondView()
.tabItem {
Text("2")
}
.tag(2)
}
// global, for all child views
.navigationBarTitle(Text(navigationBarTitle), displayMode: .inline)
.navigationBarHidden(navigationBarHidden)
.navigationBarItems(leading: navigationBarLeadingItems, trailing: navigationBarTrailingItems)
}
}
}
struct FirstView: View {
var body: some View {
NavigationLink(destination: Text("Some detail link")) {
Text("Go to...")
}
}
}
struct SecondView: View {
var body: some View {
Text("We are in the SecondView")
}
}
Compute navigationBarTitle and navigationBarItems dynamically:
private extension ContentView {
var navigationBarTitle: String {
tabSelection == 1 ? "FirstView" : "SecondView"
}
var navigationBarHidden: Bool {
tabSelection == 3
}
#ViewBuilder
var navigationBarLeadingItems: some View {
if tabSelection == 1 {
Text("+")
}
}
#ViewBuilder
var navigationBarTrailingItems: some View {
if tabSelection == 1 {
Text("-")
}
}
}
How about,
struct TabSelectionView: View {
#State private var currentTab: Tab = .Scan
private enum Tab: String {
case Scan, Validate, Settings
}
var body: some View {
TabView(selection: $currentTab){
ScanView()
.tabItem {
Label(Tab.Scan.rawValue, systemImage: "square.and.pencil")
}
.tag(Tab.Scan)
ValidateView()
.tabItem {
Label(Tab.Validate.rawValue, systemImage: "list.dash")
}
.tag(Tab.Validate)
SettingsView()
.tabItem {
Label(Tab.Settings.rawValue, systemImage: "list.dash")
}
.tag(Tab.Settings)
}
.navigationBarTitle(Text(currentTab.rawValue), displayMode: .inline)
}
}
I also faced this problem. I don't want to rewrite, but the solution is in my github. I wrote everything in detail there
https://github.com/BrotskyS/AdvancedNavigationWithTabView
P.S: I have no reputation to write comments. Hikeland's solution is not bad. But you do not save the State of the page. If you have a ScrollView, it will reset to zero every time when you change tab
Also you can create very similar custom navBar for views in TabView
struct CustomNavBarView<Content>: View where Content: View {
var title: String = ""
let content: Content
init(title: String, #ViewBuilder content: () -> Content) {
self.title = title
self.content = content()
}
var body: some View {
content
.safeAreaInset(edge: .top, content: {
HStack{
Spacer()
Text(title)
.fontWeight(.semibold)
Spacer()
}
.padding(.bottom, 10)
.frame(height: 40)
.frame(maxWidth: .infinity)
.background(.ultraThinMaterial)
.overlay {
Divider()
.frame(maxHeight: .infinity, alignment: .bottom)
}
})
}
}
CustomNavBarView(title: "Create ad"){
ZStack{
NavigationLink(destination: SetPinMapView(currentRegion: $vm.region, region: vm.region), isActive: $vm.showFullMap) {
Color.clear
}
Color("Background").ignoresSafeArea()
content
}
}

NavigationLink doesn't work with ScrollView inside a List in SwiftUI

I am trying to achieve Horizontal scroll of a scrollview inside a List. Which is working fine.
However, if I am adding NavigationLink to each ScrollView Element, it seems like NavigationView is unable to do his task.
I have added my code. Please have a look and let me know, what I am missing.
struct MovieHomeView: View {
#ObservedObject var moviesDataSource: MoviesHomeViewModel = MoviesHomeViewModel()
var body: some View {
NavigationView {
VStack {
HeaderView()
.frame(height: 50.0)
List {
MovieCategoryCell(category: "Now Playing", movies: moviesDataSource.nowPlayingMovies)
MovieCategoryCell(category: "Popular", movies: moviesDataSource.popularMovies)
}
.padding(.horizontal, -20)
}
.navigationBarTitle("Movies App")
.navigationBarHidden(true)
}
}
}
struct MovieCategoryCell: View {
var category: String
var movies: [MovieBaseProtocol]
init(category: String, movies: [MovieBaseProtocol]) {
self.category = category
self.movies = movies
}
var body: some View {
VStack(alignment: .leading) {
Text(category)
.font(.title)
ScrollView(.horizontal, showsIndicators: false) {
HStack {
ForEach(self.movies, id: \.id) { movie in
NavigationLink(destination: MovieUIView(movie: movie)) {
MovieCard(movie: movie)
}
}
}
}
.frame(height: 280)
}
.padding(.horizontal, 20)
}
}
I replace the Views with Text("1") and found everything was fine. So it must be something wrong inside your either/both of your views.
ForEach(self.movies, id: \.id) { movie in
NavigationLink(destination: Text("1")){// MovieUIView(movie: movie)) {
Text("1") // MovieCard(movie: movie)
}
}

SwiftUI How to push to next screen when tapping on Button

I can navigate to next screen by using NavigationButton (push) or present with PresentationButton (present) but i want to push when i tap on Buttton()
Button(action: {
// move to next screen
}) {
Text("See More")
}
is there a way to do it?
You can do using NavigationLink
Note: Please try in real device. in simulator sometimes not work properly.
struct MasterView: View {
#State var selection: Int? = nil
var body: some View {
NavigationView {
VStack {
NavigationLink(destination: DetailsView(), tag: 1, selection: $selection) {
Button("Press me") {
self.selection = 1
}
}
}
}
}
}
struct DetailsView: View {
#Environment(\.presentationMode) var presentation
var body: some View {
Group {
Button("Go Back") {
self.presentation.wrappedValue.dismiss()
}
}
}
}
As you can see to display the new view, add the NavigationLink with isActive: $pushView using <.hidden()> to hide the navigation "arrow".
Next add Text("See More") with tapGesture to make the text respond to taps. The variable pushView will change (false => true) when you click "See More" text.
import SwiftUI
struct ContentView: View {
#State var pushView = false
var body: some View {
NavigationView {
List {
HStack{
Text("test")
Spacer()
NavigationLink(destination: NewView(), isActive: $pushView) {
Text("")
}.hidden()
.navigationBarTitle(self.pushView ? "New view" : "default view")
Text("See More")
.padding(.trailing)
.foregroundColor(Color.blue)
.onTapGesture {
self.pushView.toggle()
}
}
}
}
}
}
struct NewView: View {
var body: some View {
Text("New View")
}
}
ContentView picture
NewView picture
To tap on button and navigate to next screen,You can use NavigationLink like below
NavigationView{
NavigationLink(destination: SecondView()) {
Text("Login")
.padding(.all, 5)
.frame(minWidth: 0, maxWidth: .infinity,maxHeight: 45, alignment: .center)
.foregroundColor(Color.white)
}
}
You can use NavigationLink to implement this:
struct DetailsView: View {
var body: some View {
VStack {
Text("Hello world")
}
}
}
struct ContentView: View {
#State var selection: Int? = nil
var body: some View {
NavigationView {
VStack {
NavigationLink(destination: DetailsView(), tag: 1, selection: $selection) {
Button("Press me") {
self.selection = 1
}
}
}
}
}
}

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