Since a few days, I do not receive any mail notification on answers to mail. Is it only me ?
Selecting any option will automatically load the page
Post
Replies
Boosts
Views
Activity
If I run the exact same code on MacOS 12.7 (Xcode 14.2) and MacOS 15.0.1 (Xcode 15.0.1).
In a scrollView, I display lines (lineDivider) and then a LazyVgrid, applying some offset:
ScrollView(.vertical) {
ForEach(1...50, id: \.self) { index in
LabelledDivider(label: "\(index)", color: .gray.opacity(0.1))
.offset(y: CGFloat(65*index - 50)
}
LazyVGrid(columns: gridItemLayout, spacing: 33 ) {
ForEach ($allItems.theItems) { $item in
ItemView(item: item)
}
}
.offset(y: 40)
}
In Xcode 14.2, I get the first layout and in Xcode 15.0 the second on right:
The divider line is at the same position, but the view in grid is not.
If I change
.offset(y: 40)
to
.offset(y: 60)
I get the same layout.
So my questions:
did anyone observe similar change ?
is it due to Xcode, to MacOS ?
Is it documented somewhere ?
Since the maintenance 2 days ago, it seems editor has issues. Is it only me ?
Marking a text as quote does nothing. I mark this sentence as Quote to illustrate.
Since a few hours, forum has an hectic behaviour:
most often, returns "We'll be back." page
or completely unformatted page
or partially formatted
even post page is a mess
Is it a known problem or only on my side ?
After more than 2 years of intense use of SwiftUI I appreciate many of its features, particularly the speed at which I can get some code running.
But, there are some major buts …
Screen Position,
I keep struggling with try, test, error and retry to position views relative to each others, withy many iterations to tune the x and y parameters. And preview does not help when view is too complex: I find it more reliable to test in simulator.
At the end, my code is messed with .position, .offset, … that I manually adjusted but may break if I change something elsewhere in the body.
The fact that position is relative to center of view (different from UIKit) makes it even more mind boggling.
For sure, UIKit constraints were not so easy, but you got a very stable code. That's not the case with SwiftUI
z position
In some cases, I want the View to appear on front of all others.
It may be a very simple Rectangle() with overlay, e.g., to mimic an alert.
And I struggle with the Rectangle drawn behind another view, even trying to adjust the zIndex to no avail…
Should I create an explicit View instead of creating the Rectangle directly in the body ?
So am I misusing SwiftUI, or are they points that SwiftUI should improve in the future ?
I have an app that runs eitheir as MacOS or iPadOS.
After a few changes to adapt to API differences (PasteBoard notably), app runs OK on both.
But the layout of views is messy when running on iPad.
Reason seems to be that Text are not using the same default font size, or that the same system font size does not use the same space. Same issue when using segmented picker for instance.
Configuration:
Xcode 14.2
MacOS 12.6.6
Simulator: iPad Pro (12.9") - iOS 16.2
Is it a correct analysis ?
Is there a simple workaround, to avoid the need to redesign all views for iPadOS ?
Here is the setup.
I have an UIImageView in which I write some text, using UIGraphicsBeginImageContext.
I pass this image to the OCR func:
func ocrText(onImage: UIImage?) {
let request = VNRecognizeTextRequest { request, error in
guard let observations = request.results as? [VNRecognizedTextObservation] else {
fatalError("Received invalid observations")
}
print("observations", observations.count)
for observation in observations {
if observation.topCandidates(1).isEmpty {
continue
}
}
} // end of request handler
request.recognitionLanguages = ["fr"]
let requests = [request]
DispatchQueue.global(qos: .userInitiated).async {
let ocrGroup = DispatchGroup()
guard let img = onImage?.cgImage else { return } // Conversion to cgImage works OK
print("img", img, img.width)
let (_, _) = onImage!.logImageSizeInKB(scale: 1)
ocrGroup.enter()
let handler = VNImageRequestHandler(cgImage: img, options: [:])
try? handler.perform(requests)
ocrGroup.leave()
ocrGroup.wait()
}
}
Problem is that observations is an empty array. I get the following logs:
img <CGImage 0x7fa53b350b60> (DP)
<<CGColorSpace 0x6000032f1e00> (kCGColorSpaceICCBased; kCGColorSpaceModelRGB; sRGB IEC61966-2.1)>
width = 398, height = 164, bpc = 8, bpp = 32, row bytes = 1600
kCGImageAlphaPremultipliedFirst | kCGImageByteOrder32Little | kCGImagePixelFormatPacked
is mask? No, has masking color? No, has soft mask? No, has matte? No, should interpolate? Yes 398
ImageSize(KB): 5 ko
2022-06-02 17:21:03.734258+0200 App[6949:2718734] Metal API Validation Enabled
observations 0
Which shows image is loaded and converted correctly to cgImage.
But no observations.
Now, if I use the same func on a snapshot image of the text drawn on screen, it works correctly.
Is there a difference between the image created by camera and image drawn in CGContext ?
Here is how mainImageView!.image (used in ocr) is created in a subclass of UIImageView:
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
// Merge tempImageView into mainImageView
UIGraphicsBeginImageContext(mainImageView!.frame.size)
mainImageView!.image?.draw(in: CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height), blendMode: .normal, alpha: 1.0)
tempImageView!.image?.draw(in: CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height), blendMode: .normal, alpha: opacity)
mainImageView!.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
tempImageView?.image = nil
}
I also draw the created image in a test UIImageView and get the correct image.
Here are the logs for the drawn texte and from the capture:
Drawing doesn't work
img <CGImage 0x7fb96b81a030> (DP)
<<CGColorSpace 0x600003322160> (kCGColorSpaceICCBased; kCGColorSpaceModelRGB; sRGB IEC61966-2.1)>
width = 398, height = 164, bpc = 8, bpp = 32, row bytes = 1600
kCGImageAlphaPremultipliedFirst | kCGImageByteOrder32Little | kCGImagePixelFormatPacked
is mask? No, has masking color? No, has soft mask? No, has matte? No, should interpolate? Yes 398
ImageSize(KB): 5 ko
2022-06-02 15:38:51.115476+0200 Numerare[5313:2653328] Metal API Validation Enabled
observations 0
Screen shot : Works
img <CGImage 0x7f97641720f0> (IP)
<<CGColorSpace 0x60000394c960> (kCGColorSpaceICCBased; kCGColorSpaceModelRGB; iMac)>
width = 570, height = 276, bpc = 8, bpp = 32, row bytes = 2280
kCGImageAlphaNoneSkipLast | 0 (default byte order) | kCGImagePixelFormatPacked
is mask? No, has masking color? No, has soft mask? No, has matte? No, should interpolate? Yes 570
ImageSize(KB): 5 ko
2022-06-02 15:43:32.158701+0200 Numerare[5402:2657059] Metal API Validation Enabled
2022-06-02 15:43:33.122941+0200 Numerare[5402:2657057] [WARNING] Resource not found for 'fr_FR'. Character language model will be disabled during language correction.
observations 1
Is there an issue with kCGColorSpaceModelRGB ?
I have declared an array as a State var
@State var proba : [Int] = [10, 40, 40, 10]
The array is updated in onAppear :
.onAppear {
proba = arrayOfTuples.map { (proba, _) in proba }
print("proba", proba)
}
The array is used for TextFields:
ForEach(0..<proba.count, id: \.self) { index in
TextField("N", value: $proba[index], format: .number)
.frame(width: 40)
.onChange(of: proba_kWh[index], perform: {[oldValue = proba_kWh[index]]
newValue in
print("proba onChange", index, oldValue, proba[index], newValue)
})
When View appears, I get some onChange (as initial values did change)
proba [10, 20, 60, 10] // onAppear changes 2 values: 1 and 2
proba onChange 2 40 60 60 // index 2 is changed before 1
proba onChange 1 40 20 20
I know that order of execution is not guaranteed, but in this specific case, I did thought it would be in the order of the array reading…
I'm running a simulation (SwiftUI app), which has 100 steps.
I need each step to be executed in order.
A first try was to dispatch with delay to schedule each second:
for step in 0..<100 {
DispatchQueue.main.asyncAfter(deadline: .now() + Double(step) * 1.0) {
// simulation code
}
}
Very poor results as 100 running threads are too much load for the system.
So I split in 2 stages:
for bigStep in 0..<10 {
DispatchQueue.main.asyncAfter(deadline: .now() + Double(bigStep) * 10.0 ) {
for step in 0..<10 {
DispatchQueue.main.asyncAfter(deadline: .now() + Double(step) * 1.0) {
// simulation code
}
}
}
}
It works much better, as now there are a max of 20 threads active (in fact I create more levels to limit to a max of 8 concurrent threads).
It addition, it allows to interrupt the simulation before end.
My questions:
is it the appropriate pattern ?
Would a timer be better ?
Other options ?
This is a SwiftUI Mac App.
There is an observable object with a published array
class AllObjects : ObservableObject {
@Published var theItems = [Item]()
}
In the View, observed with:
@ObservedObject var allObjects : AllObjects
Item class is :
class Item: ObservableObject, Identifiable {
let id = UUID()
var placeNo = 1
// Other properties
}
When I switch dark / light mode within the app (with a toggle)
@Environment(\.colorScheme) var colorScheme
the ObservedObject allObjects is modified: array is emptied: allObjects.theItems is now an empty array.
What could cause the change to theItems ? I have checked that the only func un which theItems is reset to [] is not called.
I tried to reply to a post : https://developer.apple.com/forums/thread/728329
But clicking on Reply button does nothing. ANd the Reply section does not show. No issue to answer to other threads.
Is it only me ?
Last night we change hour for daylight saving time (at 2:00 it would be 3:00).
So I made a simple test to set an alarm at 2:10
At 1:59, clock jumped logically to 3:00
no alarm
At 3:10, alarm rang (in fact I had turned it off and back on, but that has no influence)
I set an alarm at 3:15, of course it rang
I set a new alarm at 2:20
It rang at 3:20
Conclusion: Clock app "replicates" the alarms between 2:00 and 2:59 into 3:00 - 3:59.
Which is great, not to miss any.
Question: Is this specific to Clock app or a more general system behaviour for all time events ?
If so, there may be a side effect:
I set an event A to turn On a light at 2:45
And set event B to turn it Off at 3:15
Then B will occur before A and the light will remain On
There is no perfect solution ("warping" 2:00 - 2:59 into a minute at 3:00 would creates other issues).
Extra question: What happens on winter time ? Will alarm ring twice at 2:10 ?
I have encountered the following problem with a List.
The setup is as follows
@State private var allItems : [SomeItem]
@State private var selected : SomeItem?
// in the body
List(allItems, $selection) { theItem in …
}
where SomeItem is a struct.
When some properties of an item in allItems changes, the values that I read in theItem are not updated.
Just as if old content was cached.
I changed allItems to a computed var and everything works OK.
I read this SO thread https://stackoverflow.com/questions/74083515/swiftui-list-item-not-updated-if-model-is-wrapped-in-state
but that does not give a full explanation.
So my questions:
Is there effectively an issue here ?
when is it safe to use a State var as the Content of List ?
Is it OK (it seems) if the properties of items do not change ?
It seems also OK if the list of allItems is modified (appended, reduced) without problem changing the properties of its elements.
How to do if needed to change both allItems (append for instance) and change the properties of some items, as computed var cannot be modified.
Hope the question is clear.
I noticed today that font has changed in some sections of this forum.
2 examples:
in forums tag: https://developer.apple.com/forums/
font is apparently Times-Roman
in Swift tag: https://developer.apple.com/forums/tags/swift
font is apparently SFProText-Medium
How do we switch on/off the display of lines at top of a window.
It should be in Preferences, but I cannot find it.