I have a simple HStack containing a few views and I would like to keep one of the views ("Center") always centered. The size of the left view can change dynamically.
struct ExperimentView: View {
var body: some View {
HStack() {
Text("A")
.background(.red)
Spacer()
Text("Center")
.background(.yellow)
Spacer()
Button("B1") {
}
Button("B2") {
}
}
}
}
The Center view is not centered and moves to the right depending on the size of Text. I have tried something using alignmentGuide but I had no success.
A possible way is to wrap the "Center" text and the other views in a ZStack
struct ExperimentView: View {
var body: some View {
ZStack {
Text("Center")
.background(.yellow)
HStack {
Text("A")
.background(.red)
Spacer()
Button("B1") { }
Button("B2") { }
}
}
}
}
But this will not prevent the objects from overlapping if A becomes too wide.
I have a navigation view with tab views inside. The reason for this arrangement is to make the tab views disappear when within the navigation views.
I am trying to place a button at the top right corner of the screen (outside the safe area). If EntryView is called directly, the view correctly places the button ("Save") in the corner without use of offset() or position() view modifiers.
When the tab view is called before EntryView, the Save button appears an inch or so below where I would like it to appear. With offset() or position() I can move the button text back where I would like it to appear, but the tappable area doesn't move to the new location.
I have tried different arrangements of ZStack and VStack, but the arrangement below is the closest I have come to getting the button to work in the upper right corner.
Here is where I would like the button to appear: https://i.stack.imgur.com/AMdKQ.png
Is there any way to move the tappable area up to where the text is located?
Or is there some better way to draw the top part of the view?
This code can be dropped directly into Xcode for analysis.
struct ContentView: View {
#State private var selectedTab: Tabs = .home
var body: some View {
NavigationView {
TabView (selection: $selectedTab) {
EntryView()
.tabItem {
Label("Home", systemImage: "house.circle.fill")
}.tag(Tabs.home)
HistoryView()
.tabItem {
Label("History", systemImage: "clock.fill")
}.tag(Tabs.history)
}
}
}
}
struct EntryView: View {
var body: some View {
GeometryReader { g in
ZStack (alignment: .top) {
Color.blue
.frame(height: (g.safeAreaInsets.top) * 0.6, alignment: .top)
.ignoresSafeArea()
HStack {
Spacer()
Button(action: {
print("Save tapped!")
}) {
Text("Save")
.font(Font.title3.bold())
.foregroundColor(.red)
.offset(y: g.size.height * -0.14)
// .position(x: g.size.width * 0.90, y: g.size.height * -0.115)
}
}
.padding(.trailing, 10)
}
}
}
}
struct HistoryView: View {
var body: some View {
VStack (alignment: .leading) {
Text("History Tab")
.padding(.top)
}
}
}
enum Tabs: String {
case home
case history
}
I’m trying to add an line at the bottom of a VStack that fills to width of the VStack which is determined by the other content in the VStack, but the Rectangle I am using fills up the available space of the entire view.
struct ContentView: View {
var body: some View {
VStack {
Text("Testing123")
Rectangle().frame(height: 2)
}
}
}
How can I make the Rectangle only have the width necessary for the VStack to fit its content?
Here is one way to do it.
Put your Rectangle in an .overlay() of the VStack. Put the rectangle in its own VStack and use a Spacer to push the Rectangle to the bottom. Control the spacing between the rectangle and your original VStack by adding .padding to the last view in the VStack.
struct ContentView: View {
var body: some View {
VStack {
Text("Hi")
Text("Testing123")
Text("Bye").padding(.bottom, 10)
}
.overlay(
VStack {
Spacer()
Rectangle().frame(height: 2)
}
)
}
}
I'm not quite a SwiftUI veteran but I've shipped a couple of apps of moderate complexity. Still, I can't claim that I fully understand it and I'm hoping someone with deeper knowledge could shed some light on this issue:
I have some content that I want to toggle on and off, not unlike .sheet(), but I want more control over it. Here is some "reconstructed" code but it should be able capture the essence:
struct ContentView: View {
#State private var isShown = false
var body: some View {
GeometryReader { g in
VStack {
ZStack(alignment: .top) {
// This element "holds" the size
// while the content is hidden
Color.clear
// Content to be toggled
if self.isShown {
ScrollView {
Rectangle()
.aspectRatio(1, contentMode: .fit)
.frame(width: g.size.width) // This is a "work-around"
} // ScrollView
.transition(.move(edge: .bottom))
.animation(.easeOut)
}
} // ZStack
// Button to show / hide the content
Button(action: {
self.isShown.toggle()
}) {
Text(self.isShown ? "Hide" : "Show")
}
} // VStack
} // GeometryReader
}
}
What it does is, it toggles on and off some content block (represented here by a Rectangle within a ScrollView). When that happens, the content view in transitioned by moving in from the bottom with some animation. The opposite happens when the button is tapped again.
This particular piece of code works as intended but only because of this line:
.frame(width: g.size.width) // This is a "work-around"
Which, in turn, requires an extra GeometryReader, otherwise, the width of the content is animated, producing an unwanted effect (another "fix" I've discovered is using the .fixedSize() modifier but, to produce reasonable effects, it requires content that assumes its own width like Text)
My question to the wise is: is it possible to nicely transition in content encapsulated within a ScrollView without using such "fixes"? Alternatively, is there a more elegant fix for that?
A quick addition to the question following #Asperi's answer: contents should remain animatable.
You are my only hope,
–Baglan
Here is a solution (updated body w/o GeometryReader). Tested with Xcode 11.4 / iOS 13.4
var body: some View {
VStack {
ZStack(alignment: .top) {
// This element "holds" the size
// while the content is hidden
Color.clear
// Content to be toggled
if self.isShown {
ScrollView {
Rectangle()
.aspectRatio(1, contentMode: .fit)
.animation(nil) // << here !!
} // ScrollView
.transition(.move(edge: .bottom))
.animation(.easeOut)
}
} // ZStack
// Button to show / hide the content
Button(action: {
self.isShown.toggle()
}) {
Text(self.isShown ? "Hide" : "Show")
}
} // VStack
}
I'm trying to achieve a following layout using Swift UI…
struct ContentView : View {
var body: some View {
List(1...5) { index in
HStack {
HStack {
Text("Item number \(index)")
Spacer()
}.padding([.leading, .top, .bottom])
.background(Color.blue)
Text("i")
.font(.title)
.italic()
.padding()
.aspectRatio(1, contentMode: .fill)
.background(Color.pink)
}.background(Color.yellow)
}
}
}
I'd like the Text("i") to be square, but setting the .aspectRatio(1, contentMode: .fill) doesn't seem to do anything…
I could set the frame width and height of the text so it's square, but it seems that setting the aspect ratio should achieve what I want in a more dynamic way.
What am I missing?
I think this is what you're looking for:
List(1..<6) { index in
HStack {
HStack {
Text("Item number \(index)")
Spacer()
}
.padding([.leading, .top, .bottom])
.background(Color.blue)
Text("i")
.font(.title)
.italic()
.frame(maxWidth: .infinity, maxHeight: .infinity)
.aspectRatio(1, contentMode: .fill)
.background(Color.pink)
.fixedSize(horizontal: true, vertical: false)
.padding(.leading, 6)
}
.padding(6)
.background(Color.yellow)
}
The answer being said, i don't recommend giving SwiftUI too much freedom to decide the sizings. one of the biggest SwiftUI problems right now is the way it decides how to fit the views into each other. if something goes not-so-good on SwiftUI's side, it can result in too many calls to the UIKit's sizeToFit method which can slowdown the app, or even crash it.
but, if you tried this solution in a few different situations and it worked, you can assume that in your case, giving SwiftUI the choice of deciding the sizings is not problematic.
The issue is due to used different fonts for left/right sides, so paddings generate different resulting area.
Here is possible solution. The idea is to give right side rect based on default view size of left side text (this gives ability to track dynamic fonts sizes as well, automatically).
Tested with Xcode 12 / iOS 14
struct ContentView: View {
#State private var height = CGFloat.zero
var body: some View {
List(1...5, id: \.self) { index in
HStack(spacing: 8) {
HStack {
Text("Item number \(index)")
Spacer()
}
.padding([.leading, .top, .bottom])
.background(GeometryReader {
Color.blue.preference(key: ViewHeightKey.self, value: $0.frame(in: .local).size.height)
})
Text("i")
.italic()
.font(.title)
.frame(width: height, height: height)
.background(Color.pink)
}
.padding(8)
.background(Color.yellow)
.onPreferenceChange(ViewHeightKey.self) {
self.height = $0
}
}
}
}
struct ViewHeightKey: PreferenceKey {
typealias Value = CGFloat
static var defaultValue = CGFloat.zero
static func reduce(value: inout Value, nextValue: () -> Value) {
value += nextValue()
}
}
I managed to recreate the view in your first screenshot in SwiftUI. I wasn't sure on how much padding you wanted so I defined a private immutable variable for this value
The blue view is the one that will have the text content and could change in size so by using a GeometryReader you can get the size of the blue view and then use the height value from the size to set the width and height of the pink view. This means that whatever the height of the blue view is, the pink view will follow keeping an equal aspect ratio
The SizeGetter view below is used to get any views size using a GeometryReader and then binds that value back to a #State variable in the ContentView. Because the #State and #Binding property wrappers are being used, whenever the blueViewSize is updated SwiftUI will automatically refresh the view.
The SizeGetter view can be used for any view and is implemented using the .background() modifier as shown below
struct SizeGetter: View {
#Binding var size: CGSize;
var body: some View {
// Get the size of the view using a GeometryReader
GeometryReader { geometry in
Group { () -> AnyView in
// Get the size from the geometry
let size = geometry.frame(in: .global).size;
// If the size has changed, update the size on the main thread
// Checking if the size has changed stops an infinite layout loop
if (size != self.size) {
DispatchQueue.main.async {
self.size = size;
}
}
// Return an empty view
return AnyView(EmptyView());
}
}
}
}
struct ContentView: View {
private let padding: Length = 10;
#State private var blueViewSize: CGSize = .zero;
var body: some View {
List(1...5) { index in
// The yellow view
HStack(spacing: self.padding) {
// The blue view
HStack(spacing: 0) {
VStack(spacing: 0) {
Text("Item number \(index)")
.padding(self.padding);
}
Spacer();
}
.background(SizeGetter(size: self.$blueViewSize))
.background(Color.blue);
// The pink view
VStack(spacing: 0) {
Text("i")
.font(.title)
.italic();
}
.frame(
width: self.blueViewSize.height,
height: self.blueViewSize.height
)
.background(Color.pink);
}
.padding(self.padding)
.background(Color.yellow);
}
}
}
In my opinion it is better to set the background colour of a VStack or HStack instead of the Text view directly because you can then add more text and other views to the stack and not have to set the background colour for each one
I was searching very similar topic "Square Text in SwiftUI", came across your question and I think I've found quite simple approach to achieve your desired layout, using GeometryProxy to set width and heigh of the square view from offered geometry.size.
Checkout the code below, an example of TableCellView which can be used within List View context:
import SwiftUI
struct TableCellView: View {
var index: Int
var body: some View {
HStack {
HStack {
Text("Item number \(index)")
.padding([.top, .leading, .bottom])
Spacer()
}
.background(Color(.systemBlue))
.layoutPriority(1)
GeometryReader { geometry in
self.squareView(geometry: geometry)
}
.padding(.trailing)
}
.background(Color(.systemYellow))
.padding(.trailing)
}
func squareView(geometry: GeometryProxy) -> some View {
Text("i")
.frame(width: geometry.size.height, height: geometry.size.height)
.background(Color(.systemPink))
}
}