Background
Using SwiftUI, I want to implement tutorial(Coach marks) functionalities for some view( like button, text, image and so on) which was defined without specifying origin and sizes
for modifier frame. especially such functionalities will be asked for several difference screen.
My Test Code
1. Definition of PreferenceKey
struct MyPreferenceKey: PreferenceKey {
static var defaultValue: CGRect = .zero
static func reduce(value: inout CGRect, nextValue: () -> CGRect) {
value = nextValue()
}
}
main view
struct ContentView: View {
#State var rating : Int = 3
var body: some View {
GeometryReader { geometry in
let origin = geometry.frame(in: .global).origin
let size = geometry.frame(in: .global).size
VStack {
HStack{
Text("Test1") // for testing following target,just add some view hierachy
.padding()
.background(Color.yellow)
VStack{
Text("test2")
.padding()
.background(Color.purple)
Text("") // here is my target, i want to get the origin of this view
.frame(width: 100, height: 200) // just for having spece to show value of frame
.background(Color.green)
.overlay(
GeometryReader { proxy in
let frm = proxy.frame(in: .global)
let size = proxy.size
Color.clear.preference(key: MyPreferenceKey.self,value: proxy.frame(in: .global))
Text(verbatim: "X=\(String(format: "%.2f", frm.midX)) y=\(String(format: "%.2f", frm.midY) ) width=\(String(format: "%.2f", frm.width)) height=\(String(format: "%.2f", frm.height))")
}
)
}
}
.onPreferenceChange(MyPreferenceKey.self){
print("\($0)")
}
}
.frame(width: 200, height: 300, alignment: .center)
}
}
}
3. Ran result (Xcode)
4.Ran result (Log)
(89.83333333333331, 127.16666666666669, 100.0, 200.0)
5. Problem
the view with green background says it's origin.x is 139, but logs printed above is 89 in modifier onPreferenceChange.
My Question:
how can i get real origin.x with 139 using like modifier onPreferenceChange.
is there a way to get value shown by above Text view
thanks.
Related
I have a view in SwiftUI. This view has some random images on it in various random positions. Check the code below.
struct ContentView: View {
let screenWidth = UIScreen.main.bounds.width
let screenHeight = UIScreen.main.bounds.height
var body: some View {
ZStack {
ForEach(0..<5) { _ in
Image(systemName: "plus")
.frame(width: 30, height: 30)
.background(Color.green)
.position(
x: CGFloat.random(in: 0..<screenWidth),
y: CGFloat.random(in: 0..<screenHeight)
)
}
}
.ignoreSafeArea()
}
}
I need to get the exact position of these random added images and pass the positions to another transparent view that shows up with a ZStack on top of the previous view. In the transparent popup fullscreen ZStack view i need to point to the position of the images i randomly put in the previous view using arrow images. Is this somehow possible in swiftui? I am new in swiftui so any help or suggestion appreciated.
Store the random offsets in a #State var and generate them in .onAppear { }. Then you can use them to position the random images and pass the offsets to the overlay view:
struct ContentView: View {
#State private var imageOffsets: [CGPoint] = Array(repeating: CGPoint.zero, count: 5)
#State private var showingOverlay = true
let screenWidth = UIScreen.main.bounds.width
let screenHeight = UIScreen.main.bounds.height
var body: some View {
ZStack {
ForEach(0..<5) { index in
Image(systemName: "plus")
.frame(width: 30, height: 30)
.background(Color.green)
.position(
x: imageOffsets[index].x,
y: imageOffsets[index].y
)
}
}
.ignoresSafeArea()
.onAppear {
for index in 0..<5 {
imageOffsets[index] = CGPoint(x: .random(in: 0..<screenWidth), y: .random(in: 0..<screenHeight))
}
}
.overlay {
if showingOverlay {
OverlayView(imageOffsets: imageOffsets)
}
}
}
}
struct OverlayView: View {
let imageOffsets: [CGPoint]
var body: some View {
ZStack {
Color.clear
ForEach(0..<5) { index in
Circle()
.stroke(.blue)
.frame(width: 40, height: 40)
.position(
x: imageOffsets[index].x,
y: imageOffsets[index].y
)
}
}
.ignoresSafeArea()
}
}
Problem:I have a View that I needed to place multiple (2) views that contained: 1 Image + 1 Text. I decided to break that up into a ClickableImageAndText structure that I called on twice. This works perfectly if the image is a set size (64x64) but I would like this to work on all size classes. Now, I know that I can do the following:
if horizontalSizeClass == .compact {
Text("Compact")
} else {
Text("Regular")
}
but I am asking for both Different Size Classes and Same Size Classes such as the iPhone X and iPhone 13 which are the same.
Question:How do I alter the image for dynamic phone sizes (iPhone X, 13, 13 pro, etc) so it looks appropriate for all measurements?
Code:
import SwiftUI
struct ClickableImageAndText: View {
let image: String
let text: String
let tapAction: (() -> Void)
var body: some View {
VStack {
Image(image)
.resizable()
.scaledToFit()
.frame(width: 64, height: 64)
Text(text)
.foregroundColor(.white)
}
.contentShape(Rectangle())
.onTapGesture {
tapAction()
}
}
}
struct InitialView: View {
var topView: some View {
Image("Empty_App_Icon")
.resizable()
.scaledToFit()
}
var bottomView: some View {
VStack {
ClickableImageAndText(
image: "Card_Icon",
text: "View Your Memories") {
print("Tapped on View Memories")
}
.padding(.bottom)
ClickableImageAndText(
image: "Camera",
text: "Add Memories") {
print("Tapped on Add Memories")
}
.padding(.top)
}
}
var body: some View {
ZStack {
GradientView()
VStack {
Spacer()
topView
Spacer()
bottomView
Spacer()
}
}
}
}
struct InitialView_Previews: PreviewProvider {
static var previews: some View {
InitialView()
}
}
Image Note:My background includes a GradientView that I have since removed (thanks #lorem ipsum). If you so desire, here is the GradientView code but it is unnecessary for the problem above.
GradientView.swift
import SwiftUI
struct GradientView: View {
let firstColor = Color(uiColor: UIColor(red: 127/255, green: 71/255, blue: 221/255, alpha: 1))
let secondColor = Color(uiColor: UIColor(red: 251/255, green: 174/255, blue: 23/255, alpha: 1))
let startPoint = UnitPoint(x: 0, y: 0)
let endPoint = UnitPoint(x: 0.5, y: 1)
var body: some View {
LinearGradient(gradient:
Gradient(
colors: [firstColor, secondColor]),
startPoint: startPoint,
endPoint: endPoint)
.ignoresSafeArea()
}
}
struct GradientView_Previews: PreviewProvider {
static var previews: some View {
GradientView()
}
}
Effort 1:Added a GeometryReader to my ClickableImageAndText structure and the view is automatically changed incorrectly.
struct ClickableImageAndText: View {
let image: String
let text: String
let tapAction: (() -> Void)
var body: some View {
GeometryReader { reader in
VStack {
Image(image)
.resizable()
.scaledToFit()
.frame(width: 64, height: 64)
Text(text)
.foregroundColor(.white)
}
.contentShape(Rectangle())
.onTapGesture {
tapAction()
}
}
}
}
Effort 2:Added a GeometryReader as directed by #loremipsum's [deleted] answer and the content is still being pushed; specifically, the topView is being push to the top and the bottomView is taking the entire space with the addition of the GeometryReader.
struct ClickableImageAndText: View {
let image: String
let text: String
let tapAction: (() -> Void)
var body: some View {
GeometryReader{ geo in
VStack {
Image(image)
.resizable()
.scaledToFit()
//You can do this and set strict size constraints
//.frame(minWidth: 64, maxWidth: 128, minHeight: 64, maxHeight: 128, alignment: .center)
//Or this to set it to be percentage of the size of the screen
.frame(width: geo.size.width * 0.2, alignment: .center)
Text(text)
}.foregroundColor(.white)
//Everything moves to the left because the `View` expecting a size vs stretching.
//If yo want the entire width just set the View with on the outer most View
.frame(width: geo.size.width, alignment: .center)
}
.contentShape(Rectangle())
.onTapGesture {
tapAction()
}
}
}
The possible solution is to use screen bounds (which will be different for different phones) as reference value to calculate per-cent-based dynamic size for image. And to track device orientation changes we wrap our calculations into GeometryReader.
Note: I don't have your images, so added white borders for demo purpose
struct ClickableImageAndText: View {
let image: String
let text: String
let tapAction: (() -> Void)
#State private var size = CGFloat(32) // some minimal initial value (not 0)
var body: some View {
VStack {
Image(image)
.resizable()
.scaledToFit()
// .border(Color.white) // << for demo !!
.background(GeometryReader { _ in
// GeometryReader is needed to track orientation changes
let sizeX = UIScreen.main.bounds.width
let sizeY = UIScreen.main.bounds.height
// Screen bounds is needed for reference dimentions, and use
// it to calculate needed size as per-cent to be dynamic
let width = min(sizeX, sizeY)
Color.clear // % (whichever you want)
.preference(key: ViewWidthKey.self, value: width * 0.2)
})
.onPreferenceChange(ViewWidthKey.self) {
self.size = max($0, size)
}
.frame(width: size, height: size)
Text(text)
.foregroundColor(.white)
}
.contentShape(Rectangle())
.onTapGesture {
tapAction()
}
}
}
How could you achieve Icons like that?
I know that the base is this:
Image(systemName: "person.fill")
And than you could give it a background-Color:
Image(systemName: "person.fill")
.background(Color.blue)
To get rounded corners you could just add cornerRadius:
Image(systemName: "person.fill")
.background(Color.blue)
.cornerRadius(5)
But how would you make it that each of the items is in a square box with the same size?
Because SF Symbols don't have the same size.
And I don't want to make this:
Image(systemName: "person.fill")
.frame(width: 20, height: 20)
.background(Color.blue)
.cornerRadius(5)
The frame modifier would destroy the ability of SF Symbols to match with the preferred Font Size of the User.
Is there an other solution?
Or do you think the Settings App is done with .frame()?
Okay, I found an answer at Medium.
He works with Labels and adds an custom Modifier to them.
The Modifier looks like that:
struct ColorfulIconLabelStyle: LabelStyle {
var color: Color
var size: CGFloat
func makeBody(configuration: Configuration) -> some View {
Label {
configuration.title
} icon: {
configuration.icon
.imageScale(.small)
.foregroundColor(.white)
.background(RoundedRectangle(cornerRadius: 7 * size).frame(width: 28 * size, height: 28 * size).foregroundColor(color))
}
}
}
I did some changes:
struct ColorfulIconLabelStyle: LabelStyle {
var color: Color
func makeBody(configuration: Configuration) -> some View {
Label {
configuration.title
} icon: {
configuration.icon
.font(.system(size: 17))
.foregroundColor(.white)
.background(RoundedRectangle(cornerRadius: 7).frame(width: 28, height: 28).foregroundColor(color))
}
}
}
You can use it like that:
NavigationLink {
//Destination
} label: {
Label("Your Text", systemImage: "Your Image").labelStyle(ColorfulIconLabelStyle(color: .green))
}
This achieves a very native look :)
As I mentioned, full credits to Luca J.
I recommend this down way for you the update for my answer would be reading the device is zoomed or not! Then we could gave correct size for your UI, you can change your wished size in class.
struct ContentView: View {
var body: some View {
CustomButtonView(string: "gear", action: { print("setting!") })
CustomButtonView(string: "lasso.sparkles", action: { print("lasso!") })
CustomButtonView(string: "xmark.bin", action: { print("xmark!") })
CustomButtonView(string: "command", action: { print("command!") })
CustomButtonView(string: "infinity", action: { print("infinity!") })
}
}
struct CustomButtonView: View {
let string: String
let action: (() -> Void)?
init(string: String, action: (() -> Void)? = nil) {
self.string = string
self.action = action
}
#State private var tapped: Bool = Bool()
var body: some View {
Image(systemName: string)
.resizable()
.scaledToFit()
.frame(width: DeviceReader.shared.size - 5.0, height: DeviceReader.shared.size - 5.0)
.foregroundColor(Color.white)
.padding(5.0)
.background(tapped ? Color.blue : Color.gray)
.cornerRadius(10.0)
.onTapGesture { tapped.toggle(); action?() }
.animation(.interactiveSpring(), value: tapped)
}
}
class DeviceReader: ObservableObject {
let size: CGFloat
init() {
switch UIDevice.current.userInterfaceIdiom {
case .phone: self.size = 30.0
case .pad: self.size = 40.0
case .mac: self.size = 50.0
default: self.size = 30.0 }
}
static let shared: DeviceReader = DeviceReader()
}
I was looking at this question and your answer to it because this would be a useful thing to have. However, your answer does not allow the SFFont to scale with user preferences, and the answer you found on the Medium post does not scale well, as you can't just scale up and down with theses things. They look weird. If you run it in the simulator and change the Text setting, your will see what I mean.
I would simply use a .frame that changes it's size based off a preference key on the SF Symbol itself, and giving it a bit of padding extra. You could also simply add .padding() before your .background(), but the background would not necessarily be square. This method will set the width and height of the frame to slightly more than the biggest dimension of the SF Symbol, and it will fluidly change its size, not only allowing you to drop a .font() on it, but also handle the dynamic font sizes. This is a pure SwiftUI answer, using no UIKit.
struct ColoredIconView: View {
let imageName: String
let foregroundColor: Color
let backgroundColor: Color
#State private var frameSize: CGSize = CGSize(width: 30, height: 30)
#State private var cornerRadius: CGFloat = 5
var body: some View {
Image(systemName: imageName)
.overlay(
GeometryReader { proxy in
Color.clear
.preference(key: SFSymbolKey.self, value: max(proxy.size.width, proxy.size.height))
}
)
.onPreferenceChange(SFSymbolKey.self) {
let size = $0 * 1.05
frameSize = CGSize(width:size, height: size)
cornerRadius = $0 / 6.4
}
.frame(width: frameSize.width, height: frameSize.height)
.foregroundColor(foregroundColor)
.background(
RoundedRectangle(cornerRadius: cornerRadius)
.fill(backgroundColor)
)
}
}
fileprivate struct SFSymbolKey: PreferenceKey {
typealias Value = CGFloat
static var defaultValue = CGFloat.zero
static func reduce(value: inout Value, nextValue: () -> Value) {
value += nextValue()
}
}
Use it like this:
ColoredIconView(imageName: "airplane", foregroundColor: .white, backgroundColor: .orange)
.font(.body)
I have a List made of cells, each containing an image, and a column of text, which I wish laid out in a specific way. Image on the left, taking up a quarter of the width. The rest of the space given to the text, which is left-aligned.
Here's the code I got:
struct TestCell: View {
let model: ModelStruct
var body: some View {
HStack {
Image("flag")
.resizable()
.aspectRatio(contentMode: .fit)
.frame(width: UIScreen.main.bounds.size.width * 0.25)
VStack(alignment: .leading, spacing: 5) {
Text("Country: Moldova")
Text("Capital: Chișinău")
Text("Currency: Leu")
}
.frame(minWidth: 0, maxWidth: .infinity, alignment: .leading)
}
}
}
struct TestCell_Previews: PreviewProvider {
static var previews: some View {
TestCell()
.previewLayout(.sizeThatFits)
.previewDevice("iPhone 11")
}
}
And here are 2 examples:
As you can see, the height of the whole cell varies based on the aspect ratio of the image.
$1M question - How can we make the cell height hug the text (like in the second image) and not vary, but rather shrink the image in a scaleAspectFit manner inside the allocated rectangle
Note!
The text's height can vary, so no hardcoding.
Couldn't make it work with PreferenceKeys, as the cells will be part of a List, and there's some peculiar behaviour I'm trying to grasp around cell reusage, and onPreferenceChange not being called when 2 consecutive cells have the same height. To exhibit all this combined behaviour, make sure your model varies between cells when you test it.
Here is a possible solution, however it uses GeometryReader inside the background property of the VStack, to detect their height. That height is being applied to the Image then. I used SizePreferenceKey from this solution.
struct SizePreferenceKey: PreferenceKey {
typealias Value = CGSize
static var defaultValue: Value = .zero
static func reduce(value _: inout Value, nextValue: () -> Value) {
_ = nextValue()
}
}
struct ContentView6: View {
#State var childSize: CGSize = .zero
var body: some View {
HStack {
Image("image1")
.resizable()
.aspectRatio(contentMode: .fit)
.frame(width: UIScreen.main.bounds.size.width * 0.25, height: self.childSize.height)
VStack(alignment: .leading, spacing: 5) {
Text("Country: Moldova")
Text("Capital: Chișinău")
Text("Currency: Leu")
}
.frame(minWidth: 0, maxWidth: .infinity, alignment: .leading)
.background(
GeometryReader { proxy in
Color.clear.preference(key: SizePreferenceKey.self, value: proxy.size)
}
)
}
.onPreferenceChange(SizePreferenceKey.self) { preferences in
self.childSize = preferences
}
.border(Color.yellow)
}
}
Will look like this.. you can apply different aspect ratios for the Image of course.
This is what worked for me to constrain a color view to the height of text content in a cell:
A height reader view:
struct HeightReader: View {
#Binding var height: CGFloat
var body: some View {
GeometryReader { proxy -> Color in
update(with: proxy.size.height)
return Color.clear
}
}
private func update(with value: CGFloat) {
guard value != height else { return }
DispatchQueue.main.async {
height = value
}
}
}
You can then use the reader in a compound view as a background on the view you wish to constrain to, using a state object to update the frame of the view you wish to constrain:
struct CompoundView: View {
#State var height: CGFloat = 0
var body: some View {
HStack(alignment: .top) {
Color.red
.frame(width: 2, height: height)
VStack(alignment: .leading) {
Text("Some text")
Text("Some more text")
}
.background(HeightReader(height: $height))
}
}
}
struct CompoundView_Previews: PreviewProvider {
static var previews: some View {
CompoundView()
}
}
I have found that using DispatchQueue to update the binding is important.
I am making a custom Picker in the SegmentedPickerStyle(). I want to have the same behaviour but when I tap on the area between the content and the border of one of the possible selections the onTapGesture does not work. When I add a blue background it does work but with a clear background it doesn't.
Working with blue background
Not working with clear background
Not working code:
import SwiftUI
struct PickerElementView<Content>: View where Content : View {
#Binding var selectedElement: Int
let content: () -> Content
#inlinable init(_ selectedElement: Binding<Int>, #ViewBuilder content: #escaping () -> Content) {
self._selectedElement = selectedElement
self.content = content
}
var body: some View {
GeometryReader { proxy in
self.content()
.fixedSize(horizontal: true, vertical: true)
.frame(minWidth: proxy.size.width, minHeight: proxy.size.height)
// ##################################################################
// CHANGE COLOR HERE TO BLUE TO MAKE IT WORK
// ##################################################################
.background(Color.clear)
// ##################################################################
.border(Color.yellow, width: 5)
}
}
}
struct PickerView: View {
#Environment (\.colorScheme) var colorScheme: ColorScheme
var elements: [(id: Int, view: AnyView)]
#Binding var selectedElement: Int
#State var internalSelectedElement: Int = 0
private var width: CGFloat = 220
private var height: CGFloat = 100
private var cornerRadius: CGFloat = 20
private var factor: CGFloat = 0.95
private var color = Color(UIColor.systemGray)
private var selectedColor = Color(UIColor.systemGray2)
init(_ selectedElement: Binding<Int>) {
self._selectedElement = selectedElement
self.elements = [
(id: 0, view: AnyView(PickerElementView(selectedElement) {
Text("9").font(.system(.title))
})),
(id: 1, view: AnyView(PickerElementView(selectedElement) {
Text("5").font(.system(.title))
})),
]
self.internalSelectedElement = selectedElement.wrappedValue
}
func calcXPosition() -> CGFloat {
var pos = CGFloat(-self.width * self.factor / 4)
pos += CGFloat(self.internalSelectedElement) * self.width * self.factor / 2
return pos
}
var body: some View {
ZStack {
Rectangle()
.foregroundColor(self.selectedColor)
.cornerRadius(self.cornerRadius * self.factor)
.frame(width: self.width * self.factor / CGFloat(self.elements.count), height: self.height - self.width * (1 - self.factor))
.offset(x: calcXPosition())
.animation(.easeInOut(duration: 0.2))
HStack {
ForEach(self.elements, id: \.id) { item in
item.view
.gesture(TapGesture().onEnded { _ in
print(item.id)
self.selectedElement = item.id
withAnimation {
self.internalSelectedElement = item.id
}
})
}
}
}
.frame(width: self.width, height: self.height)
.background(self.color)
.cornerRadius(self.cornerRadius)
.padding()
}
}
struct PickerView_Previews: PreviewProvider {
static var previews: some View {
PickerView(.constant(1))
}
}
Change the color where I marked it.
Does anyone know why they behave differently and how I can fix this?
The one line answer is instead of setting backgroundColor, please set contentShape for hit testing.
var body: some View {
GeometryReader { proxy in
self.content()
.fixedSize(horizontal: true, vertical: true)
.frame(minWidth: proxy.size.width, minHeight: proxy.size.height)
// ##################################################################
// CHANGE COLOR HERE TO BLUE TO MAKE IT WORK
// ##################################################################
.contentShape(Rectangle())
// ##################################################################
.border(Color.yellow, width: 5)
}
}
Transparent views are not tappable by default in SwiftUI because their content shape is zero.
You can change this behavior by using .contentShape modifier:
Color.clear
.frame(width: 300, height: 300)
.contentShape(Rectangle())
.onTapGesture { print("tapped") }
It appears to be a design decision that any Color with an opacity of 0 is untappable.
Color.clear.onTapGesture { print("tapped") } // will not print
Color.blue.opacity(0).onTapGesture { print("tapped") } // will not print
Color.blue.onTapGesture { print("tapped") } // will print
Color.blue.opacity(0.0001).onTapGesture { print("tapped") } // will print
You can use the 4th option to get around this, as it is visually indistinguishable from the 1st.
I was struggling a similar problem to get the tap on a RoundedRectangle.
My simple solution was to set the opacity to a very low value and it worked
RoundedRectangle(cornerRadius: 12)
.fill(Color.black)
.opacity(0.0001)
.frame(width: 32, height: 32)
.onTapGesture {
...
}