How can I chage the text color for large titles? I want it to be white.I tried to set the titleTextAttributes like this:self.navigationController?.navigationBar.prefersLargeTitles = true
self.navigationController?.navigationBar.titleTextAttributes = [
NSAttributedStringKey.foregroundColor.rawValue: UIColor.white
]But the text only turns up white when I scroll and it is displayed in the middle as usual.
I have a performance issue with List when I have a large amount of data that is replaced. Given the code below, a data set of about 3500 name items are loaded from a fetch request. Depending of the selected gender in the segmented picker these items are filtered and the displayed in the List. When the List first render I have no performance issue with the loading and rendering of items. It scrolls nicely and smoothly through 1700 items. But as soon as I switch gender through the segemented picker it takes about 30-45 seconds to render the List again.I think this has to do with removing 1700 items and the inserting 1500 items again from the List. Is there a best practice how to reload a large amount of items in SwiftUI? Or can I reset the List before I load it again, since there is no issue initially.Anyone else having issue same issue?struct NameList: View {
@ObservedObject fileprivate var global = GlobalSettings()
@FetchRequest(
entity: Name.entity(),
sortDescriptors: [NSSortDescriptor(key: "name", ascending: true)]
) var names: FetchedResults<Name>
@State var selectedGender = Defaults.gender
var body: some View {
let filtered = names.filter { $0.gender == self.selectedGender }
return NavigationView {
VStack {
Picker("Gender", selection: $global.gender) {
Text(Gender.female.rawValue.uppercased())
.tag(Gender.female)
Text(Gender.male.rawValue.uppercased())
.tag(Gender.male)
Text(Gender.unisex.rawValue.uppercased())
.tag(Gender.unisex)
}
.pickerStyle(SegmentedPickerStyle())
.padding()
List( filtered, id: \.self) { (item: Name) in
NameListRow(item: item)
}
}
}
.onReceive(Defaults.publisher(for: \.gender)) { (gender) in
self.selectedGender = gender
}
}
}
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I having issues trying to understand combine and publishers. I have a PhotoPicker that selects one ore more images from the photo library. These images should be added to my core data model. This is handled in my model class.
However, I ends up in an infinit loop that I don't understand. The View keeps updating and the onReceive method keeps executing over and over again making the View render again. Below is a sample code (without core data) that behaves the same
Sample code:
struct MyImage: Hashable {
var id: String
var uiImage: UIImage
}
class Model: ObservableObject {
@Published var images: [MyImage] = []
func add(uiImage: UIImage) {
let id = UUID().uuidString
let image = MyImage(id: id, uiImage: uiImage)
self.images.append(image)
}
}
struct ContentView: View {
@StateObject var model = Model()
@State var showPhotoPicker = false
@State var pickerResult: [UIImage] = []
var body: some View {
VStack {
ForEach(model.images, id: \.self) { image in
Text(image.id)
				// TODO: Add actual image
}
Button(action: { showPhotoPicker.toggle() }) {
Text("ADD PHOTO")
}
.fullScreenCover(isPresented: $showPhotoPicker) {
let config = PHPickerConfiguration(photoLibrary: PHPhotoLibrary.shared())
PhotoPicker(configuration: config, pickerResult: $pickerResult)
}
}
.onReceive(pickerResult.publisher, perform: { image in
model.add(uiImage: image)
})
}
}
Can someone explain what is happening?
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Ever since I updated to iOS 14 beta 5 I have issues with my apps on the device as well as simulator. The app wont start and it just show a blank screen. The cpu, disc and network activity just show zero.
Even if you create a new project and just build from the example it wont work. Anyone else experiencing this?
The apps are build with SwiftUI.
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Can anyone help me with this? I try to use the LazyVGrid and load images from CoreData stored in a binary data field. How can I make the image loading asynchronous? I have tried to look how ImageLoader's for remote images work, but I can't make it work with images loading from CoreData.
My ImageLoader works but the ScrollView freeze until all images are loaded.
protocol ImageLoaderModel {
func thumbnailData() -> Data?
func thumbnailCacheKey() -> String
}
struct ContentView: View {
@FetchRequest(
entity: Item.entity(),
sortDescriptors: [NSSortDescriptor(key: "name", ascending: true)]
) private var items: FetchedResults<Item>
var columns: [GridItem] = [
GridItem(.adaptive(minimum: 150))
]
var body: some View {
ScrollView {
LazyVGrid(columns: columns, alignment: .center, spacing: 20) {
ForEach(items, id: \.self) { item in
GridItemView(item: item)
}
}
.padding()
}
}
}
struct GridItemView: View {
@ObservedObject var item: Item
var body: some View {
VStack(alignment: .center) {
if item.thumbnail != nil {
AsyncImage(model: item)
} else {
RoundedRectangle(cornerRadius: 5)
.frame(width: 150, height: 112)
}
Text(item.name ?? "")
.font(.subheadline)
}
}
}
struct AsyncImage: View {
@ObservedObject private var loader: ImageLoader
init(model: ImageLoaderModel) {
loader = ImageLoader(model: model)
}
var body: some View {
image.onAppear(perform: loader.load)
}
private var image: some View {
Group {
if loader.uiImage != nil {
Image(uiImage: loader.uiImage!)
.resizable()
.scaledToFill()
.frame(width: 150, height: 112)
.cornerRadius(5)
.clipped()
} else {
ProgressView()
.frame(width: 150, height: 112)
}
}
}
}
class ImageLoader: ObservableObject {
@Published var uiImage: UIImage?
private var model: ImageLoaderModel
private var cache = ImageCache.shared
init(model: ImageLoaderModel) {
self.model = model
}
func load() {
let cacheKey = self.model.thumbnailCacheKey()
if let uiImage = cache[cacheKey] {
self.uiImage = uiImage
return
}
DispatchQueue.global(qos: .userInitiated).async { [weak self] in
guard let data = self?.model.thumbnailData() else { return }
if let uiImage = UIImage(data: data) {
DispatchQueue.main.async {
self?.cache[cacheKey] = uiImage
self?.uiImage = uiImage
return
}
}
}
}
}
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When I using a ScrollView the title isn't smoothly animated up to the inline version when I scroll. Just by changing the ScrollView to a List makes it scroll as it should. Is this a known issue ?
struct ContentView: View {
var body: some View {
NavigationView {
ScrollView {
Text("Hello, world!").padding()
}
.navigationTitle("Title")
}
}
}
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Is there a way to have a list in SwiftUI that has a max width in grouped style like the Settings app on an iPad Pro 12.9" ?
I have tried with something like:
List {
	 Text("Hello, world!").padding()
}
.frame(maxWidth: 600)
.listStyle(InsetGroupedListStyle())
and it gets me half the way. The list is centered with the max width. However, I can't set the background in a way that it covers the whole page. The List view sets its background to the system grouped background as expected for InsetGroupedListStyle. And I can wrap the list in a HStack and set a background on that. But the list even add background color up in the navigation bar, but that I cannot change. So I still can't figure out a way to do it.
HStack {
	Spacer()
	List {
		Text("Hello, world!").padding()
	}
.frame(maxWidth: 600)
.listStyle(InsetGroupedListStyle())
Spacer()
}
.background(Color(UIColor.systemGroupedBackground))
I can probably accomplish what I want with just a ScrollView and make my own list. But I think that will reduce the performance?
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Is this a feature that is missing in SwiftUI at the moment?I want to achieve something like below, but for SwiftUI:cell.selectionStyle = .nonelistRowBackground change the background even if not selected..listRowBackground(Color.blue)
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How can I do a conditional check for iPadOS ? I would have expected something like:#if targetEnvironment(iPadOS)
...
#endifor#if os(iPadOS)
...
#endifto work, but none of them do. I know how to do it by checking UIUserInterfaceIdiom, but I really thoguht one of the above would work.
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Is there a way to change the selection color of a List in SwiftUI?
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I try to create a CloudKit and Core Data application in iOS13.I want two stores, one local and one Cloud enabled store. I have created 3 entities in the xcdatamodel, "Favorite", "Statistic" and "NameItem". I have also created two configurations, "Local" and "Cloud", and added one entity to "Cloud" configuration and two entities to the "Local" configuration. The entity in the "Cloud" configuration has NO relationship to the other entities. But the two entities in the "Local" configuration has relationship to each other.When I enable CloudKit for the Cloud configuration I get an error stating:"CloudKit Integration: Statistic.nameItem destination entity NameItem is missing from these configurations: Cloud""CloudKit Integration: NameItem.statistics destination entity Statistic is missing from these configurations: Cloud"But the entities "Statistic" and "NameItem" does only reside inside the Local configuration and doesn't have any relationship to the third entity "Favorite".Is this a bug or am I doing something wrong?
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"Core Data with CloudKit uses a specific record zone in the CloudKit private database, which is accessible only to the current user."It's not possible to use CloudKit and CoreData with the CloudKit public database? Here is my scenario.- I have an application with two core data stores.- The first store should be synced with the public CloudKit database and NOT updated by the user.- The second store should be synced with the private CloudKit database and updated by the user.lazy var persistentContainer: NSPersistentCloudKitContainer = {
let container = NSPersistentCloudKitContainer(name: "MyAppName")
// Create a store description for the first store
let firstStoreLocation = URL(fileURLWithPath: "/path/to/first.store")
let firstStoreDescription = NSPersistentStoreDescription(url: firstStoreLocation)
firstStoreDescription.configuration = "First"
// Create a store descpription for the second store
let secondtoreLocation = URL(fileURLWithPath: "/path/to/second.store")
let secondStoreDescription = NSPersistentStoreDescription(url: secondtoreLocation)
secondStoreDescription.configuration = "Second"
// Set the container options on the first store
firstStoreDescription.cloudKitContainerOptions =
NSPersistentCloudKitContainerOptions(containerIdentifier: "com.my.container1")
// Set the container options on the second store
secondStoreDescription.cloudKitContainerOptions =
NSPersistentCloudKitContainerOptions(containerIdentifier: "com.my.container2")
// Update the container's list of store descriptions
container.persistentStoreDescriptions = [
firstStoreDescription,
secondStoreDescription
]
// Load both stores
container.loadPersistentStores { storeDescription, error in
guard error == nil else {
fatalError("Could not load persistent stores. \(error!)")
}
}
return container
}()This code would setup sync with two stores and two different containers with private databases?It would be great if you could use the same container but different databases.
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This code below worked fine in beta 4, but crashes in beta 5. From what I can see the reason is the frame and idealHeight property.The text could be of different length and I want to show max 2 lines of data. I can't find anything that points to a changed behavior for idealHeight in beta 5.List(items, id:\.objectID) { item in
Text(item.text ?? "")
.foregroundColor(.secondary)
.font(.caption)
.lineLimit(2)
.frame(idealHeight: .infinity)
}.onAppear {
self.store.performFetch()
}If I remove the frame property, it ends up with only one row and ellipsis.How can I achieve a dynimc height of text inside each row of a list in beta 5?
sverin.