I want to register a certain drag gesture on any SwiftUI view, including ScrollViews simultaneously with any other gestures (i.e. without influencing existing gestures). However, when adding a DragGesture on a ScrollView as follows, it seems like the gesture is immediately swallowed by the ScrollView.
ScrollView {
Rectangle()
.frame(width: 500, height: 500)
}
.simultaneousGesture(
DragGesture()
.onChanged { value in
print("changed:", value.translation)
}
.onEnded { value in
print("ended:", value.translation)
}
)
When I drag the Rectangle, this code prints:
changed: (3.0, 16.666671752929688)
for example.
So onChanged is only called once, onEnded is never called.
Is there a way to make DragGestures work with ScrollViews as well?
Note:
I tried to find a workaround with GestureState and the updating(_:) modifier as well, but it didn't work either.
Related
To my knowledge, the only way to assign a navigation bar a background color that is separate from the rest of the screen, you set the background color to whatever object you have flush with the navigation view. (In this case, its a divider with the background set to red)
My intention is to then place a view flush to the divider in an attempt to create some sort of "subtitle view". The problem is, as you can see, there is a space between my Stack and my Divider... I'm not sure what is causing this space and I am not sure how to get rid of it.
My first thought was, perhaps there is some safe area being adhered to... That said, I tried ignoring that, but that didn't work.
struct ContentView: View {
var body: some View {
NavigationStack {
VStack {
Divider()
.background(.red)
.navigationTitle("Main Title")
// There is a space here
ZStack {
Rectangle().frame(height: 35)
Text("Subtitle View")
.foregroundColor(.white)
}.edgesIgnoringSafeArea([.top, .bottom])
Spacer()
}.background(.blue)
}
}
}
I have a horizontal ScrollView on top of a MapView.
The ScorllView is a collection of Buttons. It is weird that the buttons in the ScrollView are sometime tapable and sometimes not. First tap always works but after that I have to scroll a bit, tap around different areas in the button, make some secret prayers and then it works!
I tried disabling/removing all other components in the view, but still unable to figure out the root cause.
Has anyone experience this ?
I stuck with a same issue with horizontal ScrollView on top and List. While debugging I added empty .onTapGesture to ScrollView and it somehow fix my issue.
VStack(spacing: 0) {
ScrollView(.horizontal) {
HStack {
Button("one") {}
Button("two") {}
Button("three") {}
}
}
.onTapGesture { // <---- fix
}
List {
}
}
I also faced the same issue for Horizontal Scroll view in Swiftui dark theme "CameraTimerItem" buttons not clickable (Problem with dark theme only). Then I put a onTapGesture without any action. It's starts to work normally. I think it's a error of SwiftUI.
VStack (alignment:.center){
ScrollView(.horizontal, showsIndicators: false) {
HStack{
ForEach(timeSlots,id: \.self) { item in
CameraTimerItem(cellTitle: item)
}
}
.frame(width: AppUtils.width, alignment: .center)
}
.onTapGesture {
// <---- This is the solution
}
}
To anyone else having this issue, instead of adding an empty .onTapGesture view modifier, check that any HStacks in the ScrollView hierarchy have a .contentShape(Rectangle()) modifier. By default, HStacks don't accept taps in between their child views, and depending on your child view's layout this can cause taps to be missed even when it looks like they should be landing. .contentShape(Rectangle()) makes the entire frame of the HStack tappable.
I have set up a TabView in my application, so that I can swipe horizontally between multiple pages, but I also have an unwanted vertical scroll that may appear, with a bounce effect so. How can I disable this vertical scroll?
My code:
struct ContentView: View {
#State private var currentTabIndex: Double = 0
var body: some View {
VStack {
TabView(selection: $currentTabIndex) {
Text("Text n°1")
.tag(0)
Text("Text n°2")
.tag(1)
}
.border(Color.black)
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .never))
}
}
}
I had this same problem. It's not an exact solution, but you can turn off bouncing on scrollviews (which is used within a TabView). And as long as the items within the TabView are not larger than the TabView frame, it should act as if you disabled vertical scrolling.
I would call it either .onAppear or in your init function:
.onAppear(perform: {
UIScrollView.appearance().bounces = false
})
Note: this disables the bouncing on ALL scrollviews across your app... So you may want to re-enable it .onDisappear.
Still an issue with Xcode 12.4.
I managed to workaround that by wrapping the TabView within a ScrollView and using the alwaysBounceVertical property set to false, as follow:
ScrollView(.horizontal) {
TabView {
///your content goes here
}
.tabViewStyle(PageTabViewStyle())
}
.onAppear(perform: {
UIScrollView.appearance().alwaysBounceVertical = false
})
.onDisappear(perform: {
UIScrollView.appearance().alwaysBounceVertical = true
})
I actually came across this because I saw this effect in a tutorial but couldn’t replicate it on iOS 15.2. However, I managed to replicate it on iOS 14.4 on another simulator side by side. So I guess this behaviour is disabled or fundamentally changed in the newer iOS.
Demonstration
I have two views (VStacks) one on top of the other in a ZStack
The first VStack that is behind the second view is used like a menu. The second view that is on top, is the main application view.
When i click on a button i'm scaling down the main view and move it a bit to the right side of the screen to show the menu.
I have a ScrollView inside the main view every time i scale down or up the main view, the animation doesn't work smoothly the page flickers and it looks ugly. if i remove the ScrollView it works perfectly fine.
I tried to replace the ScrollView with a List but it didn't solve the problem the flickering remains the same.
Is there any way to fix this glitch?
below is a sample code
struct ContentView: View {
var body: some View {
ZStack {
Menu()
VStack {
ScrollView(.vertical, showsIndicators: false) {
VStack(spacing:0) {
Header()
MainAppView()
}
}
TabBar()
}
.scaleEffect(self.openMenu ? 0.5 : 1, anchor: UnitPoint(x: 1.5, y: 0.5))
.animation(.easeInOut(duration: 0.2))
}
}
}
Please click to check animated gif example
What you can try is, to make screenshot of the flickering view and then do the animation with the screenshot which you just add on the real view. After the animation just remove the screenshot. Of course you have to make the screenshot programmatically.
I can't repeat all the behavior, because of lack of code. I think you have this problem, because you're scaling down ScrollView and it recomputes all the content. Try just to make some offset for it, instead of scaling and there should be no flickers:
// replace this
.scaleEffect(self.openMenu ? 0.5 : 1, anchor: UnitPoint(x: 1.5, y: 0.5))
// with this:
.offset(x: self.openMenu ? 300 : 0)
I'm embedding a view controller with variable-height UITextView inside a parent SwiftUI VStack and the view controller sizes it's frame to the whole screen between viewDidLoad and viewDidLayoutSubviews. The UITextView expands only to the size of the text inside itself and centers itself inside the parent view.
I'm trying to add this view controller in a VStack and have it behave externally like other SwiftUI components do - sized exactly to the content it contains - but it wants to be sized to the whole screen minus the other VStack elements.
I can get the correct size of the UITextView in didLayoutSubviews and pass it upwards to SwiftUI where it can be set properly - but where do I do that?
In the example screenshot below, the orange is the embedded UIView background, the green is the UITextView and the VStack looks like this:
VStack {
HighligherVC()
Text("Tap and drag to highlight")
.foregroundColor(.gray)
.font(.caption)
}
Without being able to see more of your code, it's slightly difficult to say what the best solution would be, but based purely on this part of your question...
I can get the correct size of the UITextView in didLayoutSubviews and pass it upwards to SwiftUI where it can be set properly - but where do I do that?
I would suggest that you pass a binding property to your view controller that can be set to the calculated text view height, meaning that the view that contains your VStack would have a #State property like this:
#State private var textViewHeight: CGFloat = 0
You would then declare a #Binding property on your HighlighterVC and add an initializer like this:
#Binding var textViewHeight: CGFloat
init(textViewHeight: Binding<CGFloat>) {
self._textViewHeight = textViewHeight
}
And then you would set textViewHeight to the calculated height in your didLayoutSubviews and add a .frame modifier to your HighlighterVC like this:
VStack {
HighlighterVC(textViewHeight: self.$textViewHeight)
.frame(height: self.textViewHeight)
Text("Tap and drag to highlight")
.foregroundColor(.gray)
.font(.caption)
}
Like I said at the beginning of my answer, this solution (that I believe would work, but since I can't test it, I'm not 100% certain) is based on your thoughts about what it is that you need. Without seeing more code, it's impossible for me to say if this is the best solution.
Add fixedSize may solve this.
.fixedSize(horizontal: false, vertical: true)