So I have two buttons on the bottom of my screen, button A and button B, somewhere along the line I need to replace the image in the button with text, so we do so by changing the Bool in the top.
Although we apply the same modifiers, the padding of button B changes, and the UI moves around, it seems as if the text claims more space. Desired situation: button A and B, should not move around when changing the button Image to Text.
import SwiftUI
private var showImage: Bool = true
struct SwiftUIView: View {
var body: some View {
VStack {
Spacer()
Button(action: {
print("CLICK")
}) {
Image(systemName: "a.circle")
.modifier(TestButtonModifier())
}
.padding(10)
Button(action: {
print("CLICK")
}) {
if showImage {
Image(systemName: "b.circle")
.modifier(TestButtonModifier())
} else {
Text("B")
.modifier(TestButtonModifier())
}
}
.padding(10)
} //: VSTACK
}
}
struct TestButtonModifier: ViewModifier {
func body(content: Content) -> some View {
content
.font(.system(size: 52, weight: .regular))
.frame(minWidth: 0, maxWidth: .infinity, maxHeight: 100)
.background(Color.black)
.padding(2)
.foregroundColor(Color.white)
}
}
struct SwiftUIView_Previews: PreviewProvider {
static var previews: some View {
SwiftUIView()
}
}
It is due to VStack spacing, which by default differs between different pairs of subviews, so specify some explicit (or remove at all, ie set to zero)
struct SwiftUIView: View {
var body: some View {
VStack(spacing: 0) { // << here !!
// .. other code
Related
Please tell me how to put a button on top of the picture (picture below), it should be located in the lower right corner of itself. And this button should lead to another screen (navigationview). Thanks in advance !
For a long time I tried to figure it out on my own, but nothing worked.
You can take reference from this code.
import SwiftUI
struct ContentView: View {
var body: some View {
ZStack{
Button (action: {})
{
VStack{
ZStack{
VStack{
Image("image")
.resizable()
.overlay {
Button {
// any action
} label: {
Text("Let's Get acquainted")
.font(.system(size: 50))
.foregroundColor(.white)
.bold()
.position(x: 150, y: 100)
}
}
}
}
}
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
You need to use either a ZStack or .overlay:
Using ZStack:
ZStack(alignment: .bottomTrailing) {
//your content
//your image
}
Using .overlay:
//your content
.overlay(alignment: .bottomTrailing) {
//your Button
}
I am having an alignment problem while using SwiftUI.
Maybe I should say a layout issue. Anyway here is the situation:
This is the relevant part of the app interface:
One can see that while the text ("+++++") is centered, the flag is not. It is slightly shifted to the left. This left-shifting is precisely my problem. I would like the image to be centered as the text is.
Here follows the code, I would like to know what I am doing wrong for the image not to be centered:
import SwiftUI
struct TheNiceView: View {
........
var body: some View {
VStack {
HStack {
Spacer()
TheButtonView()
Spacer()
}
HStack {
Spacer()
Button(action: {})
{
Text("+++++")
.font(.largeTitle)
.foregroundColor(.gray)
.fontWeight(.heavy)
}
Spacer()
}
}
}
}
struct TheButtonView: View {
........
let imgSide:CGFloat = 72.0
var body: some View {
HStack {
Button(action: {})
{
Image(uiImage: ThaiFlagImg)
.resizable()
.frame(width: imgSide, height: imgSide)
}
}
}
}
Just in case this may be useful, this is the image used for the flag:
1
Thailand flag has five horizontal stripes in the colours red, white, blue, white and red. The image you use has 7 srtips.
2
Using the Spacers and HStack are unnecessary.
I used the following image without the Spacers and HStack, both the +++ button and the flag are aligned in the center.
https://upload.wikimedia.org/wikipedia/commons/a/a9/Flag_of_Thailand.svg
struct TheNiceView: View {
var body: some View {
VStack {
TheButtonView()
Button(action: {}) {
Text("+++++")
.font(.largeTitle)
.foregroundColor(.gray)
.fontWeight(.heavy)
}
}
}
}
struct TheButtonView: View {
let imgSide:CGFloat = 72.0
var body: some View {
Button(action: {}){
Image( "ThaiFlagImg")
.resizable()
.frame(width: imgSide, height: imgSide)
}
}
}
I have a complex view in List row:
var body: some View {
VStack {
VStack {
FullWidthImageView(ad)
HStack {
Text("\(self.price) \(self.ad.currency!)")
.font(.headline)
Spacer()
SwiftUI.Image(systemName: "heart")
}
.padding([.top, .leading, .trailing], 10.0)
Where FullWidthImageView is view with defined contexMenu modifier.
But when I long-press on an image I see not the only image in preview, but all row view.
There is no other contextMenu on any element.
How to make a preview in context with image only?
UPD. Here is a simple code illustrating the problem
We don't have any idea why in your case it doesn't work, until we see your FullWidthImageView and how you construct the context menu. Asperi's answer is working example, and it is correctly done! But did it really explain your trouble?
The trouble is that while applying .contextMenu modifier to only some part of your View (as in your example) we have to be careful.
Let see some example.
import SwiftUI
struct FullWidthImageView: View {
#ObservedObject var model = modelStore
var body: some View {
VStack {
Image(systemName: model.toggle ? "pencil.and.outline" : "trash")
.resizable()
.aspectRatio(contentMode: .fit)
.frame(width: 200)
}.contextMenu(ContextMenu {
Button(action: {
self.model.toggle.toggle()
}) {
HStack {
Text("toggle image to?")
Image(systemName: model.toggle ? "trash" : "pencil.and.outline")
}
}
Button("No") {}
})
}
}
class Model:ObservableObject {
#Published var toggle = false
}
let modelStore = Model()
struct ContentView: View {
#ObservedObject var model = modelStore
var body: some View {
VStack {
FullWidthImageView()
Text("Long press the image to change it").bold()
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
while running, the "context menu" modified View seems to be "static"!
Yes, on long press, you see the trash image, even though it is updated properly while you dismiss the context view. On every long press you see trash only!
How to make it dynamic? I need that the image will be the same, as on my "main View!
Here we have .id modifier. Let see the difference!
First we have to update our model
class Model:ObservableObject {
#Published var toggle = false
var id: UUID {
UUID()
}
}
and next our View
FullWidthImageView().id(model.id)
Now it works as we expected.
For another example, where "standard" state / binding simply doesn't work check SwiftUI hierarchical Picker with dynamic data crashes
UPDATE
As a temporary workaround you can mimic List by ScrollView
import SwiftUI
struct Row: View {
let i:Int
var body: some View {
VStack {
Image(systemName: "trash")
.resizable()
.aspectRatio(contentMode: .fit)
.frame(width: 200)
.contextMenu(ContextMenu {
Button("A") {}
Button("B") {}
})
Text("I don’t want to show in preview because I don’t have context menu modifire").bold()
}.padding()
}
}
struct ContentView: View {
var body: some View {
VStack {
ScrollView {
ForEach(0 ..< 20) { (i) in
VStack {
Divider()
Row(i: i)
}
}
}
}
}
}
It is not optimal, but in your case it should work
Here is a code (simulated possible your scenario) that works, ie. only image is shown for context menu preview (tested with Xcode 11.3+).
struct FullWidthImageView: View {
var body: some View {
Image("auto")
.resizable()
.aspectRatio(contentMode: .fit)
.frame(width: 200)
.contextMenu(ContextMenu() {
Button("Ok") {}
})
}
}
struct TestContextMenu: View {
var body: some View {
VStack {
VStack {
FullWidthImageView()
HStack {
Text("100 $")
.font(.headline)
Spacer()
Image(systemName: "heart")
}
.padding([.top, .leading, .trailing], 10.0)
}
}
}
}
It's buried in the replies here, but the key discovery is that List is changing the behavior of .contextMenu -- it creates "blocks" that pop up with the menu instead of attaching the menu to the element specified. Switching out List for ScrollView fixes the issue.
I have an HStack:
struct BottomList: View {
var body: some View {
HStack() {
ForEach(navData) { item in
NavItem(image: item.icon, title: item.title)
}
}
}
}
How do I perfectly center its content with equal spacing automatically filling the whole width?
FYI just like Bootstraps CSS class .justify-content-around
The frame layout modifier, with .infinity for the maxWidth parameter can be used to achieve this, without the need for an additional Shape View.
struct ContentView: View {
var data = ["View", "V", "View Long"]
var body: some View {
VStack {
// This will be as small as possible to fit the data
HStack {
ForEach(data, id: \.self) { item in
Text(item)
.border(Color.red)
}
}
// The frame modifier allows the view to expand horizontally
HStack {
ForEach(data, id: \.self) { item in
Text(item)
.frame(maxWidth: .infinity)
.border(Color.red)
}
}
}
}
}
The various *Stack types will try to shrink to the smallest size possible to contain their child views. If the child view has an ideal size, then the *Stack will not expand to fill the screen. This can be overcome by placing each child on top of a clear Rectangle in a ZStack, because a Shape will expand as much as possible. A convenient way to do this is via an extension on View:
extension View {
func inExpandingRectangle() -> some View {
ZStack {
Rectangle()
.fill(Color.clear)
self
}
}
}
You can then call it like this:
struct ContentView: View {
var data = ["View", "View", "View"]
var body: some View {
VStack {
// This will be as small as possible to fit the items
HStack {
ForEach(data, id: \.self) { item in
Text(item)
.border(Color.red)
}
}
// Each item's invisible Rectangle forces it to expand
// The .fixedSize modifier prevents expansion in the vertical direction
HStack {
ForEach(data, id: \.self) { item in
Text(item)
.inExpandingRectangle()
.fixedSize(horizontal: false, vertical: true)
.border(Color.red)
}
}
}
}
}
You can adjust the spacing on the HStack as desired.
I inserted Spacer() after each item...but for the LAST item, do NOT add a Spacer():
struct BottomList: View {
var body: some View {
HStack() {
ForEach(data) { item in
Item(title: item.title)
if item != data.last { // match everything but the last
Spacer()
}
}
}
}
}
Example list that is evenly spaced out even when item widths are different:
(Note: The accepted answers .frame(maxWidth: .infinity) did not work for all cases: it did not work for me when it came to items that have different widths)
If items are fullwidth compatible, it will be done automatically, you can wrap items between spacers to make it happen:
struct Resizable: View {
let text: String
var body: some View {
HStack {
Spacer()
Text(text)
Spacer()
}
}
}
So you. can use it in a loop like:
HStack {
ForEach(data, id: \.self) { item in
Resizable(text: item)
}
}
You can also use spacing in stacks ... ie
HStack(spacing: 30){
Image("NetflixLogo")
.resizable()
.scaledToFit()
.frame(width: 40)
Text("TV Show")
Text("Movies")
Text("My List")
}
.frame(maxWidth: .infinity)
output result looks like this ...
If your array has repeating values, use array.indices to omit a spacer after the last element.
HStack() {
ForEach(data.indices) { i in
Text("\(data[i])")
if i != data.last {
Spacer()
}
}
}
my tapAction is not recognizing a tap when my foregroundColor is clear. When i remove the color it works fine.
That's my code:
ZStack {
RoundedRectangle(cornerRadius: 0)
.foregroundColor(Color.clear)
.frame(width: showMenu ? UIScreen.main.bounds.width : 0)
.tapAction {
self.showMenu.toggle()
}
RoundedRectangle(cornerRadius: 5)
.foregroundColor(Color.green)
.shadow(radius: 5, y: 2)
.padding(.trailing, 50)
.frame(width: showMenu ? UIScreen.main.bounds.width : 0)
}
.edgesIgnoringSafeArea(.top)
The accurate way is to use .contentShape(Rectangle()) on the view.
Described in this tutorial:
control-the-tappable-area-of-a-view by Paul Hudson #twostraws
VStack {
Image("Some Image").resizable().frame(width: 50, height: 50)
Spacer().frame(height: 50)
Text("Some Text")
}
.contentShape(Rectangle())
.onTapGesture {
print("Do Something")
}
how-to-control-the-tappable-area-of-a-view-using-contentshape stackoverflow
I have also discovered that a shape filled with Color.clear does not generate a tappable area.
Here are two workarounds:
Use Color.black.opacity(0.0001) (even on 10-bits-per-channel displays). This generates a color that is so transparent that it should have no effect on your appearance, and generates a tappable area that fills its frame. I don't know if SwiftUI is smart enough to skip rendering the color, so I don't know if it has any performance impact.
Use a GeometryReader to get the frame size, and then use the contentShape to generate the tappable area:
GeometryReader { proxy in
Color.clear.contentShape(Path(CGRect(origin: .zero, size: proxy.size)))
}
Here is the component
struct InvisibleButton: View {
let action: (() -> Void)?
var body: some View {
Color.clear
.contentShape(Rectangle())
.onTapGesture {
action?()
}
}
}
usage: Put your view and InbisibleButton in ZStack
ZStack {
**yourView()**
InvisibleButton {
print("Invisible button tapped")
}
}
you also can make a modifier to simplify usage:
struct InvisibleButtonModifier: ViewModifier {
let action: (() -> Void)?
func body(content: Content) -> some View {
ZStack {
content
InvisibleButton(action: action)
}
}
}
**yourView()**
.modifier(InvisibleButtonModifier {
print("Invisible button tapped")
})
However, if your SwiftUI View has a UIKit view as a subview under, you will have to set Color.gray.opacity(0.0001) in order to UIView's touches be ignored
In my case a View that didn't trigger onTapGesture:
struct MainView: View {
var action: () -> Void
var body: some View {
NotTappableView()
.contentShape(Rectangle())
.onTapGesture(
action()
)
}
}
I solved this way:
struct MainView: View {
var action: () -> Void
var body: some View {
NotTappableView()
.overlay(
Color.clear
.contentShape(Rectangle())
.onTapGesture {
action()
}
)
}
}
This made whole untappable view now tappable.