Changing the spacing of the underline of a UIButton - swift

How can I change the spacing between a UIButton and its underline? And also try to make the underline bolder. Any help is appreciated.
My UIButton:
enter image description here
The ideal UIButton:
enter image description here

To get such a button, you can split it int 2 elements - the text (not underlined) and a rectangle (as the line).
SwiftUI
In SwiftUI you can achieve your desired design with a Stack within the button with a text and a rectangle in it
Button(action: {
self.anyFancyFunction()
}) {
VStack(){
Text("Button")
Rectangle().frame(height: 5)
}
.foregroundColor(.black)
}
And it would look like:
In this example you can adjust the spacing by adding a (positive or negative) offset. You can add a corner radius to the bar and ich you wanted to have it rounded on the edges, you also can use Capsule() instead of Rectangle()
UPDATE:
UIKit
Regarding UIKit, I think a possible solution could be to create a view with 2 subviews (1. text, 2. bar underneath the text) and then you put a clear button with the same size over it on the same position.
I'll try to add an UIKit example in the afternoon.
Best,
Sebastian

In SwiftUI, there is a View called Rectangle that is perfectly matched for this. You can add it below any view by embedding them into a simple VStack.
Here is the code:
import SwiftUI
struct ContentView: View {
var body: some View {
Button(action: {
}) {
VStack(spacing: 15){
Text("帖子")
.font(.system(size: 30))
Rectangle()
}
.frame(width: 70, height: 60, alignment: .center)
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
Here is the result:

Related

Fullscreen LazyHStack for Images (Landscape)

This is my first question ever on StackOverflow so please bear with me!
How do I get a fullscreen ScrollView with LazyHStack while ignoring safe edges with the each image taking up 100% of the device screen?
I was able to get something like this that worked using TabView but since there is no "LazyTabView" it was not an efficient way to do things.. I have also tried multiple other methods utilizing Geometry Reader and frame but to no avail. Also note that I am strictly working in landscape orientation so how it looks in portrait does not matter to me.
Here is the code I'm currently using:
import SwiftUI
struct ContentView: View {
var body: some View {
ScrollView(.horizontal, showsIndicators: false) {
LazyHStack() {
Image("test")
.resizable()
.scaledToFill()
Image("test")
.resizable()
.scaledToFill()
Image("test")
.resizable()
.scaledToFill()
Image("test")
.resizable()
.scaledToFill()
}
}
.ignoresSafeArea()
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
I have also attached an image to show the results I am getting. I am hoping I can have the image take up 100% of the screen real estate without showing the edge of the next image. As you can see the image does not fill the entire screen and instead shows the edge of the next photo. I hope this makes sense!
screenshot of code with preview
This code worked for me:
struct ContentView: View {
var body: some View {
GeometryReader { g in
ScrollView(.horizontal, showsIndicators: false) {
HStack() {
Image("test")
.resizable()
.ignoresSafeArea()
.frame(width: g.size.width + CGFloat(g.safeAreaInsets.leading) + CGFloat(g.safeAreaInsets.trailing), height: g.size.height + CGFloat(g.safeAreaInsets.bottom))
.offset(x: -CGFloat(g.safeAreaInsets.leading))
}
}
}
}
}
It will make the image take up the whole screen, ignoring the safe area. You may have to take the code out of the LazyHStack and into a HStack instead, however. Unless you have a large number of images, you do not need to use LazyHStack.

Inserting non-list elements in a SwiftUI view

I am working on a SwiftUI page that consists of a table view with some rows but I would also like to have some non-cell elements in there. I am currently having some issues with this and I have tried various different avenues. I basically just need some elements in there that aren't wrapped inside a cell while still maintaining the tableview's grayish background. In my example below, I am trying to get an image right under the table rows.
Below is my code:
import SwiftUI
struct ContentView: View {
private var color = Color(red: 32/255, green: 35/255, blue: 0/255)
var body: some View {
NavigationView {
Form {
Section() {
HStack {
Text("AA")
.foregroundColor(color)
}
HStack {
Text("B")
.foregroundColor(color)
}
HStack {
Text("C")
.foregroundColor(color)
}
HStack {
Text("D")
.foregroundColor(color)
}
HStack {
Text("E")
.foregroundColor(color)
}
HStack {
Text("F")
.foregroundColor(color)
}
HStack {
Text("G")
.foregroundColor(color)
}
}
}.navigationBarTitle(Text("Page"))
HStack {
Image(systemName: "fallLeaves")
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
Here are all of the scenarios I have tried that have been unsuccessful:
Scenario 1: Adding a HStack with the image outside of the List. (What the current code shows) This does not get the image to show as the table view takes the whole view.
Scenario 2: Adding the HStack with the image within the list block. This wraps the image around the cell like so
Scenario 3: Wrapping the list and the HStack contains the image inside a VStack. This is no good as it's basically like a split-screen with two different views. The table gets shrunk and has it's own scroll bar. Notice the scroll bar in the image below
The ideal solution would look like this but I'm not sure what to try as I can't get it to look like this where it's all one continuous view and the image isn't in a cell
i'll let you work out the padding and the rounding.
struct ContentView: View {
private var color = Color(red: 32/255, green: 35/255, blue: 0/255)
var body: some View {
NavigationView {
Form {
Section(content: {
HStack {
Text("AA")
.foregroundColor(color)
}
HStack {
Text("B")
.foregroundColor(color)
}
}, footer: {
Image("fallLeaves")
})
}.navigationBarTitle(Text("Page"))
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
You can also use place your component (event a page view) inside the cell.
What can be done;
Use a Section to have a good style when you initiate another cell (because we'll make the following one transparent)
Create a new Section
Place a / any view
Add .listRowBackground(Color.clear) to the new view; to see the background transparently.
Add .listRowSeparator(.hidden)to the new view; to remove the cell line below.
After these, you'll have a placed view with additional padding. If this is important, you can play with padding to catch 0 padding distance. Also, by changing the list style (for this second group) with these kinds of styles, .listStyle(.grouped), you can get catch zero padding/spacing.
The footer solution can work for images, but when you need some texts, you'll see that it'll scale down the sizes. So instead of footer, my solution is to use a cell view and show it as a non-cell item;
Here is my change, which works (at least I think)
import SwiftUI
struct ContentView: View {
private var color = Color(red: 32/255, green: 35/255, blue: 255/255)
// Just changed color to test my changes better.
// private var color = Color(red: 32/255, green: 35/255, blue: 0/255)
var body: some View {
NavigationView {
Form {
Section() {
Text("AA")
Text("B")
Text("C")
Text("D")
Text("E")
Text("F")
Text("G")
}
//foreground color won't colorize the cell's bottom lines
.foregroundColor(color)
Section{
HStack{
// Use Spacer or another horizontal alignment
// I just tried with another image, you can place yours with full width and remove the Spacer() 's
Spacer()
Image(systemName: "checkmark.seal.fill")
.resizable()
.scaledToFit()
.foregroundColor(color)
.frame(width: 100)
Spacer()
}
.listRowBackground(Color.clear)
// Not required for single items; but would be usefull, if you'll add more views or sections
.listRowSeparator(.hidden)
}
}.navigationBarTitle(Text("Page"))
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
And here is why your methods won't work;
Scenario 1: Using VStack and HStack will split the screen into different scrollable. This is by design, In SwiftUI List element overrides Stacks and ScrollableView
(Reference)
Scenario 2: Same as Scenario 1
Scenario 3: Actually, this is the same as Scenario 1
You might try 3 things;
My solution, I don't see a major problem
Footer solution, which can work, but for some views, you will have problems
Determine a background color in ZStack and develop a custom button object which looks like a cell view (cons: non-native way and long time consuming work around)

Arrange custom views in SwiftUI without space or overlap

I'm trying to build a UI (SwiftUI / iOS) out of a number of custom views.
All those custom views have a defined aspect ratio or ratio for their frame.
Here's a simplified version of such a custom view:
struct TestView: View {
var body: some View {
GeometryReader { geometry in
RoundedRectangle(cornerRadius: 20)
.foregroundColor(Color.blue)
.frame(height: geometry.size.width / 3)
}
}
}
My ContentView currently looks like that:
struct TestContentView: View {
var body: some View {
GeometryReader {geomerty in
VStack {
TestView()
TestView()
}
}
}
}
I would like to have the two rectangles to be positioned right below each other (at the top of the screen). So without any space between them. So a bit like an old-fashioned UITableView with only to rows.
But whatever I try, I only get one of two results:
They are equally spread out over the screen (vertically)
They overlap (= the view on the top only gets a vertical size of 20
The only solution I've found so far is to define the frame size of the sub-views also in the TestContentView(). But that seems to be quite un-SwiftUI.
Thanks!
Remove the GeometryReader from your content view, since it isn't doing anything
You said that your TestView has a defined aspect ratio, but, in fact, it doesn't -- it just has a defined width. If you do define an aspect ratio, it starts working as expected:
struct TestView: View {
var body: some View {
RoundedRectangle(cornerRadius: 20)
.foregroundColor(Color.blue)
.aspectRatio(3, contentMode: .fit)
}
}
struct TestContentView: View {
var body: some View {
VStack(spacing: 0) {
TestView()
TestView()
Spacer()
}
}
}

SwiftUI - setting the frame of view

When I learn new stuff like SwiftUI (beta 6)
I want to start from the basic.
I just want to set frame to subview like in UIKit.
What I'm missing here ? (this is from Simulator)
1. the subview is not in 0,0 position.
2. why at least the start of the word is not inside the border ?
UPDATE :
how to set the text view in 0,0 position ? (just like on UIKit)
I thought my question is very clear, but for some reason, it's not.
I think it's important to understand why your solution doesn't work because at a first glance it seems correct and it seems that SwiftUI works in some weird ways (because, of course, we are all used to UIKit).
You tried:
struct ContentView: View {
var body: some View {
VStack {
Text("Hello World")
.position(CGPoint(x: 0, y: 0))
.frame(width: 50, height: 100)
.border(Color.red, width: 4)
}
}
}
And you got:
First of all, the position modifier says:
Fixes the center of the view at the specified point in its parent’s
coordinate space.
Two things are important here:
The view is moved based on its centre, not based on its top-left corner
The view is moved in the parent's coordinate space
But who is the Text's parent? A view modifier in SwiftUI is something that applies to a View and returns a View. Modifiers are applied from the last one to the first one (in reverse order respect to how you see them). In your case:
So: The centre of the Text is positioned at (0,0) respect to a Frame 50x100 with a red Border. The resulting View is placed in the centre of the screen because of the VStack (it's the VStack default behaviour). In other words: the position's parent (position returns a View, every modifier returns a View) is the Frame 50x100 placed in the centre of the screen.
If you want to position the top-left corner of the Text at (0,0) in the Frame coordinate space you should use the Spacer modifier this way:
struct ContentView: View {
var body: some View {
VStack {
Text("Hello World")
Spacer()
}
.frame(width: 50, height: 100)
.border(Color.red, width: 4)
}
}
And you'll get:
If you want, instead, the top-left corner of the Frame to be at (0,0) respect to the whole View I think the simplest way is:
struct ContentView: View {
var body: some View {
HStack {
VStack {
Text("Hello World")
.frame(width: 50, height: 100)
.border(Color.red, width: 4)
Spacer()
}
Spacer()
}
.edgesIgnoringSafeArea(.all)
}
}
And you'll get:
Do Like this way
struct ContentView: View {
var body: some View {
VStack{
Text("Hello World")
.frame(width: 50, height: 100)
.border(Color.red, width: 4)
.padding()
Spacer()
}
}
}
Below is output
if you want to remove space on top add .edgesIgnoringSafeArea(.top) for your view like below
struct ContentView: View {
var body: some View {
VStack{
Text("Hello World")
.frame(width: 50, height: 100)
.border(Color.red, width: 4)
.padding()
Spacer()
}
.edgesIgnoringSafeArea(.top)
}
}

SwiftUI - Using GeometryReader Without Modifying The View Size

I have a header view which extends its background to be under the status bar using edgesIgnoringSafeArea. To align the content/subviews of the header view correctly, I need the safeAreaInsets from GeometryReader. However, when using GeometryReader, my view doesn't have a fitted size anymore.
Code without using GeometryReader
struct MyView : View {
var body: some View {
VStack(alignment: .leading) {
CustomView()
}
.padding(.horizontal)
.padding(.bottom, 64)
.background(Color.blue)
}
}
Preview
Code using GeometryReader
struct MyView : View {
var body: some View {
GeometryReader { geometry in
VStack(alignment: .leading) {
CustomView()
}
.padding(.horizontal)
.padding(.top, geometry.safeAreaInsets.top)
.padding(.bottom, 64)
.background(Color.blue)
.fixedSize()
}
}
}
Preview
Is there a way to use GeometryReader without modifying the underlying view size?
Answer to the question in the title:
It is possible to wrap the GeometryReader in an .overlay() or .background(). Doing so will mitigate the layout changing effect of GeometryReader. The view will be laid out as normal, the GeometryReader will expand to the full size of the view and emit the geometry into its content builder closure.
It's also possible to set the frame of the GeometryReader to stop its eagerness in expanding.
For example, this example renders a blue rectangle, and a "Hello world" text inside at 3/4th the height of the rectangle (instead of the rectangle filling up all available space) by wrapping the GeometryReader in an overlay:
struct MyView : View {
var body: some View {
Rectangle()
.fill(Color.blue)
.frame(height: 150)
.overlay(GeometryReader { geo in
Text("Hello world").padding(.top, geo.size.height * 3 / 4)
})
Spacer()
}
}
Another example to achieve the same effect by setting the frame on the GeometryReader:
struct MyView : View {
var body: some View {
GeometryReader { geo in
Rectangle().fill(Color.blue)
Text("Hello world").padding(.top, geo.size.height * 3 / 4)
}
.frame(height: 150)
Spacer()
}
}
However, there are caveats / not very obvious behaviors
1
View modifiers apply to anything up to the point that they are applied, and not to anything after. An overlay / background that is added after .edgesIgnoringSafeArea(.all) will respect the safe area (not participate in ignoring the safe area).
This code renders "Hello world" inside the safe area, while the blue rectangle ignores the safe area:
struct MyView : View {
var body: some View {
Rectangle()
.fill(Color.blue)
.frame(height: 150)
.edgesIgnoringSafeArea(.all)
.overlay(VStack {
Text("Hello world")
Spacer()
})
Spacer()
}
}
2
Applying .edgesIgnoringSafeArea(.all) to the background makes GeometryReader ignore the SafeArea:
struct MyView : View {
var body: some View {
Rectangle()
.fill(Color.blue)
.frame(height: 150)
.overlay(GeometryReader { geo in
VStack {
Text("Hello world")
// No effect, safe area is set to be ignored.
.padding(.top, geo.safeAreaInsets.top)
Spacer()
}
})
.edgesIgnoringSafeArea(.all)
Spacer()
}
}
It is possible to compose many layouts by adding multiple overlays / backgrounds.
3
A measured geometry will be available to the content of the GeometryReader. Not to parent or sibling views; even if the values are extracted into a State or ObservableObject. SwiftUI will emit a runtime warning if that happens:
struct MyView : View {
#State private var safeAreaInsets = EdgeInsets()
var body: some View {
Text("Hello world")
.edgesIgnoringSafeArea(.all)
.background(GeometryReader(content: set(geometry:)))
.padding(.top, safeAreaInsets.top)
Spacer()
}
private func set(geometry: GeometryProxy) -> some View {
self.safeAreaInsets = geometry.safeAreaInsets
return Color.blue
}
}
I tried with the previewLayout and I see what you mean. However, I think the behavior is as expected. The definition of .sizeThatFits is:
Fit the container (A) to the size of the preview (B) when offered the
size of the device (C) on which the preview is running.
I intercalated some letters to define each part and make it more clear:
A = the final size of the preview.
B = The size of what you are modifying with .previewLayout(). In the first case, it's the VStack. But in the second case, it's the GeometryReader.
C = The size of the screen of the device.
Both views act differently, because VStack is not greedy, and only takes what it needs. GeometryReader, on the other side, tries to have it all, because it does not know what its child will want to use. If the child wants to use less, it can do it, but it has to start by being offered everything.
Perhaps if you edit your question to explain exactly what you would like to accomplish, I can refine my answer a little.
If you would like GeometryReader to report the size of the VStack. you may do so by putting it inside a .background modifier. But again, I am not sure what's the goal, so maybe that's a no go.
I have written an article about the different uses of GeometryReader. Here's the link, in case it helps: https://swiftui-lab.com/geometryreader-to-the-rescue/
UPDATE
Ok, with your additional explanation, here you have a working solution. Note that the Preview will not work, because safeInsets are reported as zero. On the simulator, however, it works fine:
As you will see, I use view preferences. They are not explained anywhere, but I am currently writing an article about them that I will post soon.
It may all look too verbose, but if you find yourself using it too often, you can encapsulate it inside a custom modifier.
import SwiftUI
struct InsetPreferenceKey: PreferenceKey {
static var defaultValue: CGFloat = 0
static func reduce(value: inout CGFloat, nextValue: () -> CGFloat) {
value = nextValue()
}
typealias Value = CGFloat
}
struct InsetGetter: View {
var body: some View {
GeometryReader { geometry in
return Rectangle().preference(key: InsetPreferenceKey.self, value: geometry.safeAreaInsets.top)
}
}
}
struct ContentView : View {
var body: some View {
MyView()
}
}
struct MyView : View {
#State private var topInset: CGFloat = 0
var body: some View {
VStack {
CustomView(inset: topInset)
.padding(.horizontal)
.padding(.bottom, 64)
.padding(.top, topInset)
.background(Color.blue)
.background(InsetGetter())
.edgesIgnoringSafeArea(.all)
.onPreferenceChange(InsetPreferenceKey.self) { self.topInset = $0 }
Spacer()
}
}
}
struct CustomView: View {
let inset: CGFloat
var body: some View {
VStack {
HStack {
Text("C \(inset)").color(.white).fontWeight(.bold).font(.title)
Spacer()
}
HStack {
Text("A").color(.white)
Text("B").color(.white)
Spacer()
}
}
}
}
I managed to solve this by wrapping the page main view inside a GeometryReader and pass down the safeAreaInsets to MyView. Since it is the main page view where we want the entire screen thus it is ok to be as greedy as possible.