How to Hide TabBar in NavigationView When Using SwiftUI
Recently, more and more people are using SwiftUI
to develop iOS apps, but as a new tool SwiftUI
still has a lot of unresolved problems.
Lots of developers find they cannot hide TabBar
when they use NavigationView
to navigate to a new view in SwiftUI
. It is pretty annoying.
Here, I would like to give you guys a solution to solve this problem. I will explain some View Hierarchy
knowledge first to help you guys understand what's actually going on in swiftUI
when we try to use NavigationView
and TabView
. You can also directly jump to solution if you want to.
The Hierarchy of SwiftUI Views
Here is a demo app. In this demo, I have two tabs, tab1 and tab2, in a TabView
, and I want to tap the text in each tab to navigate to NavigatedView
. So, I add NavigationView
and NavigationLink
to the contents in each tab. The code is as below.
ContentView.swift
import SwiftUI
struct ContentView: View {
@State var tabSelection: Tabs = .tab1
var body: some View {
TabView(selection: $tabSelection){
NavigationView{ //if you write the NavigationView here, you cannot remove TabBar after navigation
NavigationLink(destination: NavigatedView()){
VStack{
Text("Here is Tab 1")
Text("Tap me to NavigatedView")
}
.navigationBarTitle("Tab1")
}
}
.tabItem { Text("Tab 1") }
.tag(Tabs.tab1)
NavigationView{//Tab2 also has a NavigationView
NavigationLink(destination: NavigatedView()){
VStack{
Text("Here is Tab 2")
Text("Tap me to NavigatedView")
}
.navigationBarTitle("Tab2")
}
}
.tabItem { Text("Tab 2") }
.tag(Tabs.tab2)
}
}
enum Tabs{
case tab1, tab2
}
}
NavigatedView.swift
import SwiftUI
struct NavigatedView: View {
var body: some View {
Text("Hi! This is the NavigatedView")
.navigationBarTitle("NavigatedView")
}
}
When running the code, there is a problem, you can see when I tap the text in Tab1
and go to the NavigatedView
, TabBar
is still at the bottom. However, when we develop an app, sometimes we really want the TabBar
to disappear when navigating.
Navigation in TabView | before navigation | after navigation |
---|---|---|
Why does it run like this? To understand this, let's take a look at View Hierarchy
in SwistUI
. When you write the NavigationView
in TabView
, the things goes in SwiftUI
like the following pictures.TabView
contains NavigationView
, and it makes everything happening in NavigationView
cannot affect TabView
, because NavigationView
is just a child-view of TabView
. So, when navigating to another view, NavigationView
changes, but as the super-view TabView
will stay what it is.
when the Tap Here to a new view button is tapped, only the red part (NavigationView ) changes to orange part (NavigatedView ), but the blue part ( TabView ) stays the same. |
---|
Here, it should be clear. If we want to hide the TabBar
, we just write TabView
into NavigationView
, making the NavigationView
the super-view and the TabView
the child-view, which is just opposite to the above View Hierarchy
.
when the Tap Here to a new view button is tapped, the blue part (NavigationView ) changes to orange part (NavigatedView ), so the TabBar in red part disappears itself. |
---|
After knowing this, we just need to modify our code a little to let NavigationView
contain TabView
and then we can perfectly solve the problem.
The Solution
Like what has been mentioned above, we just rewrite our code to make NavigationView
contain TabView
.
import SwiftUI
struct ContentView: View {
@State var tabSelection: Tabs = .tab1
var body: some View {
NavigationView{
TabView(selection: $tabSelection){
// NavigationView{ //if you write the NavigationView here, you cannot remove TabBar after navigation
NavigationLink(destination: NavigatedView()){
VStack{
Text("Here is Tab 1")
Text("Tap me to NavigatedView")
}
.navigationBarTitle("Tab1")//NavigationBarTitle does not work here
}
// }
.tabItem { Text("Tab 1") }
.tag(Tabs.tab1)
// NavigationView{//Tab2 also has a NavigationView
NavigationLink(destination: NavigatedView()){
VStack{
Text("Here is Tab 2")
Text("Tap me to NavigatedView")
}
.navigationBarTitle("Tab2")//NavigationBarTitle does not work here
}
// }
.tabItem { Text("Tab 2") }
.tag(Tabs.tab2)
}
}
}
enum Tabs{
case tab1, tab2
}
}
Another problem here is our NavigationBarTitle
does not display itself when we write it in TabView
.
Navigation in TabView | before navigation | after navigation |
---|---|---|
The solution is also easy. Just move the NavigationBarTitle
to the end of TabView
and it works fine. But in this way, when we tap different tabs, the NavigationBarTitle
is always the same, which is not what we want. So, I also added a function returnNaviBarTitle
to display the right NavigationBarTitle
based on the selected tab. The following code is the final version.
import SwiftUI
struct ContentView: View {
@State var tabSelection: Tabs = .tab1
var body: some View {
NavigationView{
TabView(selection: $tabSelection){
// NavigationView{ //if you write the NavigationView here, you cannot remove TabBar after navigation
NavigationLink(destination: NavigatedView()){
VStack{
Text("Here is Tab 1")
Text("Tap me to NavigatedView")
}
// .navigationBarTitle("Tab1")//NavigationBarTitle does not work here
}
// }
.tabItem { Text("Tab 1") }
.tag(Tabs.tab1)
// NavigationView{//Tab2 also has a NavigationView
NavigationLink(destination: NavigatedView()){
VStack{
Text("Here is Tab 2")
Text("Tap me to NavigatedView")
}
// .navigationBarTitle("Tab2")//NavigationBarTitle does not work here
}
// }
.tabItem { Text("Tab 2") }
.tag(Tabs.tab2)
}
.navigationBarTitle(returnNaviBarTitle(tabSelection: self.tabSelection))//add the NavigationBarTitle here.
}
}
enum Tabs{
case tab1, tab2
}
func returnNaviBarTitle(tabSelection: Tabs) -> String{//this function will return the correct NavigationBarTitle when different tab is selected.
switch tabSelection{
case .tab1: return "Tab1"
case .tab2: return "Tab2"
}
}
}
Navigation in TabView | before navigation | after navigation |
---|---|---|
End
Here ends the doc! Hope you have learned something. Thanks so much for your reading.