Swiftui fetchrequest predicate. The filter string is an @State property of the parent view.

Swiftui fetchrequest predicate Configure a sectioned fetch request with an optional predicate and sort descriptors, and include a section Identifier parameter to indicate I have a List with displays the result of a dynamic FetchRequest. When I attempt to use the fetch request results from the view model in a selected view, the DataTable, I get this message: Accessing StateObject's object without being installed on a View. predicate = NSPredicate(format: "name BEGINSWITH %@", query) Search For Matches That End With String. in the listView i have a button that'll change the predicate for the fetchrequest, but i can't get it to work. I'm new-ish to Swift, and trying to better understand Core Data with some (I thought!) simple projects. Anyone else seen this? – – Starting with iOS 15, it’s easier to dynamically configure a Core Data fetch request for use with SwiftUI. I fetched all the reminders and then filtered them with a predicate. NSFetchRequest propertiesToFetch. I modified my code as follows I have successfully added Core Data to my SwiftUI project. 3000), the list is built quite slowly when the dynamic predicate changed. But as projects Open in app. For example, sorted(by: \Note. Comments with ️ SwiftUI View and @FetchRequest predicate with variable that can change – gotnull. Start Here Latest Articles What's new in Swift? 100 Days of SwiftUI 100 Days of Swift Swift Knowledge Base SwiftUI by Example Swift in Sixty Seconds Hacking with Swift YouTube videos Swift Playgrounds Get the iOS App Careers. Ask Question Asked 1 year, by a simple re-design like writing a custom init that takes a Group as an argument and uses that group to create the predicate and assign it to the fetch request – Joakim Danielson. SwiftUI, Xcode 13, Question about . Your code is wrong, you've missed the line fetchRequest. I'm trying to filter Core Data by changing the predicate when typing in the search bar, but doing so causes the app to freeze. Hot Network Questions Twin sister pretends to be the other twin to get and perform a fetch request with it (more information here) let predicate = NSPredicate(format: "attribute1 == %@", "test") let request = NSFetchRequest<SomeItem>(entityName: "SomeItem") let result = try moc. Looking at your buttons (Tout, Symptomes and Traitement) and the examples you presented, I Is FetchRequest breaking the unidirectional data flow? For every developer who uses Core Data in SwiftUI, @FetchRequest is an unavoidable topic. An NSPredicate predicate that specifies which properties to filter by and the constraints on In SwiftUI, you can use a Fetch {// Create a fetch request. The three entities involved are: Meals, . 5. Forums. @FetchRequest seems to be useless if you The SwiftUI ‘searchable’ modifier. com. Call parent view's The predicate describes the attributes to filter by and the constraints to apply to those attributes. fetchLimit = 100 // Filter the request results, such as to only return SwiftUI redraws the table in response to new results. Set this configuration value to cause a FetchRequest to execute a fetch with a new predicate. It's not about relationships, it's about the difference of using predicate in NSFetchRequest and using predicate in NSSet API filteredSetUsingPredicate. Write. Swift 3. SwiftUI View and @FetchRequest predicate with variable that can change . groupBy modifier along with . date, ascending: true)], predicate: NSPredicate(format: "date == %@"), animation: . Viewed 911 times 5 I have a SwiftUI view like : @FetchRequest( entity: Message(), sortDescriptors: [NSSortDescriptor(keyPath: \Message. but having a bigger result set (e. e. default) var SwiftUI View and @FetchRequest predicate with variable that can change. creationDate, . The code works fine, but having a bigger result set (e. let request = ShoppingItem. For example, "name == %@" filters by a name value. I tried using a predicate I know will return an empty set but it seems hacky, isn't there a more standard way to do that? @FetchRequest(sortDescriptors: [ SortDescriptor(\. I tried one of the responses in this post (the Updated for Xcode 16. What I want is for the FetchRequest to be updated, when Delete Objects With Predicate. Okay so removing the lazy from the line lazy var persistentContainer: NSPersistentCloudKitContainer = {}() in the AppDelegate helped in my case. Therefore I need a fetch request for gathering all SwiftUI View and @FetchRequest predicate with variable that can change. Ask Question Asked 4 years, 8 months ago. Set this configuration value to cause a Fetch Request to execute a fetch with a new predicate. Related. default) var The FetchRequest needs to be FetchRequest<Child> as it's used in a SwiftUI view, so I can't just build an array of the results. I have a View, which has a @FetchRequest. 10. swiftUI. You can apply a series of modifiers on this object to further configure how the objects should be matched and returned. I don‘t know if it’s the best way to do this, but it took me some time to get everything to work. SwiftUI - Use value passed from previous view in predicate. SAVE 50% All our books and bundles are half price for Black Friday, so you can take your Swift knowledge further without spending big!Get the Swift Power Pack to build your iOS career faster, get the Swift Platform Pack to builds apps for macOS, watchOS, and beyond, or get the Swift Plus Pack to learn advanced design patterns, I have a List with displays the result of a dynamic FetchRequest. how to fix the error: 'property initializers run before' self 'is available' in @FetchRequest. For example, here’s a fetch request created in iOS 14: Predicate: Filters results using a query-like syntax. The request infers the entity type Jul 22, 2023 · 在SwiftUI中，@FetchRequest 的 predicate 参数用于过滤 Core Data 中的数据。通过使用 predicate 可以指定特定的条件，只获取符合条件的数据，从而对数据进行筛选和显示 Dec 1, 2022 · Core Data fetch requests can use predicates in SwiftUI just like they can with UIKit, all by providing a predicate property to your @FetchRequest property wrapper. The NSFetchRequest is created within a manager that makes a static instance of itself available to property wrappers (they cannot use self). Basically, it would sum up values of income in selected month (right now it's set to current Date() in the example code, but later on it will be set to whole current SwiftUI View and @FetchRequest predicate with variable that can change. To see @FetchRequest in action, let’s create a SwiftUI view that fetches data from a Core Data database. let query = "R" let request: NSFetchRequest<Person> = Person. SwiftUI – Hacking with Swift forums. core data. If you don’t specify a predicate, the fetch returns all models of the inferred type. FetchRequest with NSPredicate does not update on new entries. I'm having a problem with new SwiftUI. Copy link Owner. Predicate, Predicate, is a simple test that will be applied to every object in our Don’t confuse the Section view that you use to create a hierarchical display with the Sectioned Fetch Results. How to loop through a relationship in Swift 4. fetchRequest() // Limit the maximum number of items that the request returns. Here‘s an example SwiftUI CoreData project with an dynamic changeable predicate in a FetchRequest. Stack Overflow. NSFetchedResultController and UISearchBar implementation. How to use the new nsPredicate dynamic property of @FetchRequest property wrapper with object passed into View. There are several valuable hints on how to accomplish this in the Demystify SwiftUI session from this year's WWDC I'm having trouble figuring out how to make a SwiftUI @FetchRequest use a predicate only if a Boolean value stored in UserDefaults is true. Modified 6 months ago. Dynamic FetchRequest in SwiftUI. dynamic filters (predicate) in SwiftUI. You’ve stopped watching this thread and will no longer @FetchRequest always uses the managed object context from the environment; in general, you should always do the same. Fetch requests allow us to load Core Data results that match specific criteria we specify, and SwiftUI can bind those results directly to user interface elements. Articles Books Sponsorship Newsletter About. Access this value of a Fetch Request . My predicate is as follows: NSPredicate(format: "date > \(currentDate)") When I executed the fetch request I caught an exception: 'Unable to parse the format string "date > 2015-07-08 03:00:00 +0000"' I thought I could make a query like that. The same instance is passed to the view at creation. Put simply, a predicate is a filter: you specify the criteria you want to match, and Core Data will ensure that only matching objects get returned. How can I fetch all subentities in a single SwiftUI View and @FetchRequest predicate with variable that can change. Is there any way to create a FetchRequest using an EnvironmentOjbect as a NSPredicate? I read this article by Paul Hudson, which is great, but I did not want to pass in the variable to the init. Hot Network Questions 1950's Short story about civilization slowly winding backwards [Continue my comment] assuming we have Person entity and somehow stored/get some id for some object, here is a demo of possible view that get that object by id and work with it. My list filtering is slow with the current setup: struct TechList: View { @FetchRequest var devices: FetchedResults&lt;HearingDevice&gt; @State private var selectedDevice: String? @ObservedObjec Thanks malhal. filter'ing CoreData. var body: some View { List(messages. fetchRequest to fetch the data correctly. Within the @Query property wrapper, I pass the filter and sort descriptors as arguments. he changes the age from 35 to 20 years), the detail view will pop once the user taps the save button and the managed object context saves, which is registered by @fetchRequest in the list view. Open onmyway133 opened this issue Mar 14, 2020 · 0 comments Open How to update FetchRequest with predicate in SwiftUI #621. – SwiftUI View and @FetchRequest predicate with variable that can change. infinitive) ], predicate: NSPredicate(format: I am getting the correct results, but each time value or tag changes and composePredicate runs, there is a flash during which time the results show aa items as if there was no predicate. fetch(request) Apart from all the links above I recommend you also read this tutorial about Core Data: Core Data I'm trying to make a fetch for dates later than a specific date. To ensure that all items with the same category are grouped together, you can use the . If you followed my Core Data and SwiftUI set up instructions, you’ve already injected your managed object context into the SwiftUI environment. predicate = predicate; – Xcode beta 5 introduced @FetchRequest for SwiftUI. Jerry PM · Follow. Using that parameter in the @FetchRequest will cause an error, as the variable has not been initialized. That way you can vary predicate and sort conditions. Viewed 1k times Part of Mobile Development Collective 0 I have a MessagesView where I can create and delete messages. If you followed You initialize a Fetch Request with an optional predicate and sort descriptors, either explicitly or using a configured NSFetch Request. persistence. First, the properties I have in my SwiftUI view: I start with an empty predicates array, then I check my searchText and append the appropriate predicate if the condition is true. How to prevent Core Data fetch request from resetting its predicate when SwiftUI List selection changes? 5. Set configuration directly If you need to access the fetch request’s configuration elements directly, use the ns Predicate and sort Descriptors or ns Sort Descriptors properties of the Fetched Results instance. I created CoreData models Cars and Datepoints with a one-to-many relationship (one car -> many datepoints). SwiftUI - Deleting from a Core Data NSSet - I'm new-ish to Swift, and trying to better understand Core Data with some (I thought!) simple projects. wrappedValue, id: \. No answers there doesn't work code doesn't compile accessing Binding. SwiftUI - Add values from two textfields using var or let. descending) is a modifier specifying that the objects should be sorted by the creation date in the descending order. Try adding a @State var, change it from the button action and use it in the view:. fetchRequest() request. Update 30/6/2022: I realised we shouldn’t be initing NSPredicate objects inside body so need a new approach. This would essentially be static I have a core data program. Subscribe SwiftUI View and @FetchRequest predicate with variable that can change. entity(), sortDescriptors: [NSSortDescriptor(keyPath How can I limit the size of the retrieved FetchedResults when making a FetchRequest to CoreData? struct ContentView: View { var fetchRequest:FetchRequest&lt;Kana&gt; init(){ SwiftUI View and @FetchRequest predicate with variable that can change. Mark Core Data entries as Favourites SWIFTUI. Apple disclaims any and all liability for the acts, omissions and conduct of any third parties in connection with or Mar 14, 2020 · “How to update FetchRequest with predicate in SwiftUI” is published by Khoa Pham in Indie Goodies. How to use predicates with fetchRequest in Core Data. 20 Mar 2023 · 3 min read. When I use this in my view: @FetchRequest(entity: Note. SwiftUI use relationship predicate with struct parameter in FetchRequest. When you need to dynamically change the request’s section identifier, predicate, or sort descriptors, set the result instance’s section Identifier, ns Predicate, and sort Descriptors or ns Sort Descriptors properties, Discussion. environment(\. SwiftUI CoreData not in Set of relationships . The syntax for this is a little odd at first, mostly because this is actually another macro behind the scenes - Swift converts our predicate code SwiftUI View and @FetchRequest predicate with variable that can change. Hello. SwiftUI’s @FetchRequest property wrapper is great for making simple requests for objects, providing both sorting and filtering. This makes total sense in that context: do the @FetchRequest up front in the struct, and revise the predicate later after compartment has been resolved. The parent view sends the child view a predicate filter string for a FetchRequest and a Binding to return the FetchedResults count. I'm trying to use an @FetchRequest property wrapper to list child-items which belong to a given parent. hackingwithsw 1. Unreliable update with @FetchRequest predicate filtering on UUID typed attributes? Hot Network Questions D. In three places I use a Fetchrequest to check if the data is already in the database. Here's a sample code snippet to achieve this: import SwiftUI import CoreData 1. S. A SwiftUI View that displays the results of the executed fetch request. You must provide @FetchRequest with at least one value, which is an array of sort descriptors to arrange the data. Here is some sample code to achieve that. A modifier returns a mutated Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Yes, you can use a predicate for the fetchRequest, and that will limit what is fetched based on the predicate. managedObjectContext) var context @FetchRequest(fetchRequest: ItemEntity. Hot Network Questions How to say "Each one of the following" in German? The @FetchRequest property wrapper in your SwiftUI view. @FetchRequest automatically updates its fetched The FetchRequest can be dynamically created in the init method. I tried the response starting with "Edit 9/10/2023" of this post, but it kept crashing. After configuring the fetch SwiftUI – Hacking with Swift forums. Why @FetchRequest fails in ContentView. the search string) is passed into a second view which encapsulates SwiftUI View and @FetchRequest predicate with variable that can change. When I've used SwiftUI fetch requests I've always used the property wrapper syntax, and it's worked happily enough. 0 @FetchRequest predicate not updating when UserDefaults value changes SwiftUI. While this object is commonly used in conjunction GroupBy using @FetchRequest in SwiftUI. How to filter a Core Data Fetch Request by the 3rd level relationship. FetchRequest greatly simplifies the difficulty of getting Core Data data in the view. Custom Fetch Request not updating the view when adding entries to context. I have pretty much given up on @FetchRequest inside of my Views because it is so limited in functionality compared to CoreData at large. onDelete on ForEach with Alert before delete CoreData Record. Modified 2 years, Using a @FetchRequest with a predicate of parent == nil, it's possible to grab the root nodes and subsequently walk the tree using the relationships. swift. entity(), sortDescriptors: []) let notes: First you want to take a look at the response here What is the best way to do a fetch request in CoreData? to get an idea how a programmatic fetch request may look like. Commented Dec 10, 2019 at 0:10. 20 Using FetchRequest in swiftUI view model. Ask Question Asked 4 years, 11 months ago. g. Configuration structure for a given request by using the ns Predicate property on the associated Fetched Results Is this still the preferred method of customizing a FetchRequest's predicate based on a parameter passed to a view? I've been trying to use the new iOS 13 nsPredicate Dynamic Property in . The following code snippets provide you an example of how to weave all three components together. At first I thought that the problem was in the search bar, SwiftUI View and @FetchRequest predicate with variable that can change. The ENDSWITH keyboard in an NSPredicate is used to perform a search for strings that end with a specific substring. 2 Main Functions @FetchRequest simplifies the process of retrieving data from Core Data, allowing developers to define entity types, sort descriptors, and predicates to filter results. Configuration structure for a given request by using the Dec 13, 2024 · The @FetchRequest property wrapper is a convenient way to bind Core Data fetch requests to SwiftUI views. 0. Nov 23, 2023 · Instead, we’re going to create a custom initializer that accepts a filter string and uses that to set the fetchRequest property. loadItems()) var items: FetchedResults<ItemEntity> @State private var refresh: Overview. They all do have in common, that the predicate (e. onmyway133 opened this issue Mar 14, 2020 · 0 comments Labels. Example: Fetching and Displaying Tasks Learn how to request data from the Core Data store in a SwiftUI view with the @FetchRequest property wrapper. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Filter @fetchrequest using NSPredicate. 15 How to use The answer found at SwiftUI View and @FetchRequest predicate with variable that can change is essentially correct, but I discovered that the order in which things appear inside the struct matters to avoid a slew of errors. I was reading Paul Hudson’s article Dynamically filtering @FetchRequest with SwiftUI and thought I would share an improvement for declaring the singers @FetchRequest property that supports a dynamic predicate for filtering: How to update FetchRequest with predicate in SwiftUI. However, when the app is first installed and the user tries to perform a search before entering any data, the app crashes with this error: SwiftUI @FetchRequest Core Data Changes to Relationships Don't Refresh. How do you preview a view containing a binding to its parent view's state? 5. 16. EXC_BAD_ACCESS when using NSPredicate in Swift. I am trying to make dynamic filters of Core Data items with SwiftUI. struct HomeListView: View { @Environment(\. SwiftUI FetchRequest Error: 'A fetch request must have an entity' 8. What I normally do is: Create a manager-object for accessing my CoreData model (My data managers are @globalActors to more easily facilitate background fetches but this is not necessary and might complicate things for Filter @fetchrequest using NSPredicate. Start Here Interview Questions Interactive Review Test your Swift Find a I have a list that displays a CoreData FetchRequest, and I have a Picker that changes how the list is sorted. entity(), sortDescriptors: [NSSortDescriptor(keyPath: \Book. Start Here Interview Questions Interactive Review Test your Swift Find a Fetch Request Predicate to filter a Core Data entity where a small NSSet is contained within larger NSSet. Instead I wanted to use an EnvrionmentObject. ios. Share. How to cast FetchedResults<Obj> from @FetchRequest to [Obj]? 5. swift core data get objects from one to many relation. Sign up. Start Here Interview Questions Interactive Review Test your Swift Find a Job Store. SwiftUI gives us a dedicated property wrapper for working with Core Data fetch requests, and it allows us to embed data directly into SwiftUI views without having to write extra logic. onmyway133 commented Mar 14, 2020 • edited Make subview Delete Objects With Predicate. content (fetchRequest)} // This is a generic initializer that allow to provide all filtering information init (withPredicate predicate For a SwiftUI @FetchRequest. Get a quick overview on how to use predicates to filter fetch request results. Note: NSManagedObject conforms to ObservableObject. isEmpty }) var movies: [Movie] You need to change some state so that the view re-renders. 1. I have a SwiftUI app where I am using @FetchRequest along with a predicate. Swift SwiftUI – Hacking with Swift forums. 0. If you’ve opted in to email or web notifications, you’ll be notified when there’s activity. The crash happens only when deleting the last item in a section. That step is required. Sign in. If you don’t need sectioning, use Fetch Request instead. I run my fetch request in a class i. Trigger search by setting property. A change to the filter string in the parent causes the child to update the FetchRequest. 15. Hi, I am running into a reproducible SwiftUI List crash when using @FetchRequest based on an @ObservedObject. Like deleting multiple objects in Core Data using delete(_:), delete objects with a predicate in Core Data by getting objects from a fetch request, deleting those objects, and then saving the NSManagedObjectContext: // Create a fetch request with a predicate let fetchRequest: NSFetchRequest<Business> fetchRequest = SwiftUI FetchRequest predicate with data from an ObservedObject causes property initialisers run before self is available. You can further tweak a fetch by limiting the number of models it returns, or indicating whether the fetch evaluates any unsaved changes when it selects the models to return. Important: You should use ContactAccessButton initially because it's a really smooth way of reading contacts at the point It seems like you're facing an issue with grouping items by category in SwiftUI when using Core Data. I'm trying to run a basic test SwiftUI app for macOS using Core Data, and I'm hitting a problem. Issue #621. uniqueIdentifier) { message in rowView(for: message, from: messages. Using a predicate to limit the results from your fetch request: let predicate = NSPredicate(format: "favorite == true") This is best used when you want to show JUST the list of "favorite" items. 3 min read · Nov 28, 2024--Listen. From IOS 15 swiftUI has been enriched of new (wished) functionalities. date, ascending: false)] ) var allMessages: FetchedResults< Message. Core Data allows us to link entities together using relationships, and when we use @FetchRequest Core Data sends all that data back to us for use. For anyone who’s interested. 19. The issue is that the FetchedResults is not changing when the value for showAvailable changes. I have a simple swift app which provides the following functionalit Sorry guys if there's already a thread about it but been stuck with it for a while. import SwiftUI import CoreData struct FilteredList: View { var fetchRequest: FetchRequest<CDReminder> var reminders: FetchedResults<CDReminder> Core Data allows us to link entities together using relationships, and when we use @FetchRequest Core Data sends all that data back to us for use. Q. SwiftUI and dynamic NSSortDescriptors in @FetchRequest. When using SwiftUI’s @fetchRequest attribute wrapper, we can provide an array of sort descriptors to control the order of the results, and we can also provide an NSPredicate to control which results should be displayed. Comments. One of the most useful in my opinion is the new modifier searchable that allow to achieve in pretty straightforward way a full working search bar. Use a Sectioned Fetch Request property wrapper to declare a Sectioned Fetch Results property that provides a grouped collection of Core Data managed objects to a SwiftUI view. Input a dynamic value into @FetchRequest, to fetch a single entity from core data in SwiftUI 15 How to use @Fetchrequest outside a View The SwiftUI 'searchable' modifier As described in my previous article SwiftUI: Dynamically Filtering FetchRequest from IOS 15 SwiftUI has been enriched by an useful modifier searchable that allow to achieve, in pretty straightforward way a full working search bar. onAppear() and find that the @FetchRequest's predicate gets set to nil after the first time SwiftUI updates the first View update. Viewed 49 times 0 . I use a predicate with the request. Provided code creates 3 instances of Item entity. In iOS 15, Apple gave SwiftUI a more convenient version of the property wrapper for creating Core Data fetch requests. "self. Core Data Entity: Item. My problem is that when the user changes the age of a person in the detail view to some age which does not fulfil the criteria of the fetch request (e. 3 Input a dynamic value into @FetchRequest, to fetch a single entity from core data in SwiftUI. How to prevent Core Data fetch request from resetting its predicate when SwiftUI List selection changes? Hot Network i'm building a todo app with swiftUI and Core Data. Later, you can dynamically update the predicate and Nov 23, 2023 · When we use SwiftUI’s @FetchRequest property wrapper, we can provide an array of sort descriptors to control the ordering of results, but we can also provide an Feb 2, 2022 · How to combine searchable modifier with FetchRequest property wrapper to achieve dynamic filtering. Modified 4 years, 11 months ago. What am I doing wrong? SwiftUI & @FetchRequest sortDescriptors on specific data (team in this case) Ask Question Asked 5 years, 1 month ago. SwiftUI: ForEach filters boolean. Because it seemed that Apples boilerplate code handed of the NSManagedObjectModel in the line let contentView = ContentView(). In one simple line Hello. Binding var inside NSPredicate - SwiftUI. Use this initializer when you want to configure a fetch request with more than a predicate and sort descriptors. Coredata dynamic filters (predicate) in SwiftUI. Create NSPredicate with ANY and two conditions for it. In this example, we filter snippets based on whether their titles I have a pretty simple FetchRequest to fetch items where "priority" = "High". Tagged with swiftui, coredata, searchable, fetchrequest. I'm kinda new to CoreData(knows only how to persist and fetch items only) and I'm trying to do a little query in SwiftUI View and @FetchRequest predicate with variable that can change. Like deleting multiple objects in Core Data using delete(_:), delete objects with a predicate in Core Data by getting objects from a fetch request, deleting those objects, and then saving the NSManagedObjectContext: // Create a fetch request with a predicate let fetchRequest: NSFetchRequest<Business> fetchRequest = Also, if you bind them you still need to make a new fetch request in "SearchView" to get updated results, init() will not be invoked again. You've already seen how @Query can be used to sort SwiftData objects in a particular order, but it can also be used to filter that data using a predicate – a series of tests that get applied to your data, to decide what to return. Passing a bound value as an argument to a SwiftUI 2 View. SwiftUI - How to preserve child view's state when updating parent view's state? 3. fetch coredata with one to SwiftUI View and @FetchRequest predicate with variable that can change. Fetching data from a Core Data entity using I am new to swift/iOS programming and tried to fix the issue with the other threads on StackOverflow, however, I couldn't fix it. The best way to learn about predicates is by example, so I've created three examples below that demonstrate various different filters. 1. count > 10 }) var movies: [Movie] However, again here you need to be careful. fetch coredata with one to many relationship in swift. wrappedValue) } } func rowView(for message: Message, from rom IOS 15 swiftUI has been enriched of new (wished) functionalities. Add this initializer now: _fetchRequest = Use a Fetch Request property wrapper to declare a Fetched Results property that provides a collection of Core Data managed objects to a SwiftUI view. SwiftUI FetchRequest predicate with data from an ObservedObject causes property initialisers run before self is available. Core Data Many-to-Many Swift. As a passionate iOS developer, one of the most exciting features in SwiftUI for me has been the ease of data How to update FetchRequest with predicate in SwiftUI #621. I would recommend to write a single function as I have this code in my SwiftUI project in works well struct ContentView: View { @State private var selectedCountry: Country? @State private var showSetting = false @FetchRequest(entity: Country. request. Everything works fine as long as there is already some data. You then want to create a list of all these subentities in a View. In the above code example, I defined a `ContentView` struct that includes an @Query property wrapper. However, to make this work, you must make sure that your View's init() method does not get called again after onAppear is called. Section instances that hold the fetched results. date > var body: some View { NavigationView { When SwiftUI’s FetchRequest met Core Data, it felt like magic. How to Use @FetchRequest in SwiftUI. 4. struct DemoPersonView: View { @ObservedObject var person: Person init(id objectID: NSManagedObjectID, in context: SwiftUI FetchRequest predicate with data from an ObservedObject causes property initialisers run before self is available. SwiftUI View and @FetchRequest predicate with variable that can change. Learn. I alredy dealt with problem with @FetchRequest dynamic filtering and I've created a If I correctly understood your description (and taking into account that FetchedResults is a RandomAccessCollection) I would go with the following approach. Creating Fetch Requests. Access this value of a FetchRequest. Let's say you have defined an entity A in CoreData and then you make it abstract and you give it three subentities B,C and D. 在使用 SwiftUI 的@FetchRequest属性包装器时，我们可以提供一个排序描述符的数组，用于控制结果的顺序，同时我们还可以提供一个NSPredicate来控制哪些结果应该被显示。Predicate，即谓词，是简单的测试，这个测试会被应用到我们的 Core Data 译自 www. . 40. One of the most useful in my opinion is the new modifier searchable that allow to achieve in pretty straightforward way a full How to sum filtered Core Data values (using predicate) in SwiftUI app? I have 1 entity named NPTransaction. Swift Core Data NSFetchRequest no results . When using SwiftUI’s @fetchRequest attribute wrapper, Predicate, Predicate, is a simple test that will be applied to every object in our Core Data entity — only the objects that pass the test will be placed in the result array. objectID" is illegal in NSFetchRequest. 3. New in iOS 18. Core Data and Predicate. Click again to stop watching or visit your profile to manage watched threads and notifications. Using FetchRequest in a SwiftUI view model. Form first announcement I couldn’t wait to use it and as soon as I’ve updated my XCode I started to refactor one of the You can create predicates that depend on relationships, for example showing only movies with a small cast: @Query(filter: #Predicate<Movie> { movie in movie. Ask Question Asked 2 1 I'm writing a 100% SwiftUI app with iOS and macOS targets, using Core Data and NSPersistentCloudKitContainer to backup to iCloud and sync between devices signed into the same AppleID. Core Data- predicate with dates. I am not using FetchRequest in SwiftUI, as I need a predicate based on a parameter which is send to the View aswell. There are a lot great tutorials out there, how to dynamically alter the predicate of a fetchRequest like this one. 2. All other deletes and inserts (that I've tested so far) seem to work fine. This site contains user submitted content, comments and opinions and is for informational purposes only. I suspect that I can do this with a SUBQUERY predicate but I can't work out how to embed the parent predicate into the SUBQUERY. For example, you can vend a request from a Quake managed object that the Loading and Displaying a Large Data Feed sample code project defines to store earthquake data. Here, the filter descriptor uses the predicate macro, #Predicate, to define the filtering condition. However, this is one area where Core Data shows its age a little: to get relationships to work well we need to make a custom NSManagedObject subclass that providers wrappers that are more friendly to SwiftUI. How can I have the child view update the Binding it receives with the new FetchedResults count? SwiftUI View and @FetchRequest predicate with variable that can change. May 4, 2020 · 对于 SwiftUI ，我经常被问到的一个问题是：我要怎么样动态地改变一个 Core Data@FetchRequest，以便使用不同的谓词或者排序呢？大家之所以会提出这个问题是因为 fetch 请求是作为属性被创建的，因此如果你尝试让它们引用另外的属性，会被 Swift Nov 20, 2024 · SwiftUI and @FetchRequest - modify predicate or sort dynamically? First post date Last post date . I am using a SwiftUI @ FetchRequest to displays Core Data items, one of the properties of the entity is date, and I want to filter items by today's Date, this is the @ FetchRequest: @FetchRequest( entity: Book. Attributes: date (Date), done (Boolean), name (String). But if you want to adjust the number of items you get back – perhaps to say “show me the first 10 items in my results” – then you need to do a little more work yourself. As I understand your problem now, you want to write two methods getLat() and getLon() which are going to fetch the coordinates for an airport. Currently I have to relaunch the app to see the showAvailable value based results. countForFetchRequest in Swift 2. 0 @FetchRequest predicate not updating when I have 2 views in a ToDo app, one view allows the user to add new ToDos and mark them as completed and another shows a calendar that allows the user to see all the ToDos that they might have comple I'm using @FetchRequest to get a big list (+7k) of entities and I'd like to initiate the view with an empty result set which will be filled later with searchable(). Developer Footer. March 14, 2020 · 1 min · 190 words · Khoa. Limit the number of results to 1000 by setting a fetch Limit for the request: I am using a FetchRequest in a chat app and want to set the fetchLimit dynamically. and every once in a while, the new predicate in SwiftUI – Hacking with Swift forums. managedObjectContext, @FetchRequest var fetchRequest: FetchedResults < T > // this is our content closure; we'll call this once the fetch results is available let content: (FetchedResults < T >)-> Content var body: some View {self. First I want to load 50 messages, then an additional number when the user scrolls to the top of the chat message list. SwiftUI - How to toogle all the booleans in a CoreData. This will work: @Query(filter: #Predicate<Movie> { movie in movie. SwiftUI & Core Data - How do I use a parent record in a predicate? 1. a view model and assign it to a StateObject in the ContentView. This works for most cases, but not when the to-parent relationship is the only thing which would cause a child item to be displayed after a new child item is added. It has 5 attributes and I would like to sum values from the attribute named value (Integer 64). How to fetch subentities with SwiftUI @FetchRequest? Ask Question Asked 6 months ago. I need to filter the results by type. Start Here Interview Questions Interactive Review Test your Swift Find a Updated for Xcode 16. Member-only story. tanaschita. Dynamic sort descriptor FetchRequest SwiftUI. (As an aside you may also want to learn how to use compound predicates, to use with logic such as AND & OR, but that is entirely up to you, and whether you may need it in future). Coredata fetchrequest predicate doesn't show the right things. Hot Network Questions How can I connect my thick wires into an ikea wire SwiftUI View and @FetchRequest predicate with variable that can change. How can I set a fetchLimit dynamically for a SwiftUI @FetchRequest? 0. This enables the display of fetched results in your app's interface. SwiftUI has a dedicated ContactAccessButton for displaying and adding contacts in your app, along with a contactAccessPicker() modifier for adjusting access later on. Make subview that accepts FetchRequest. The filter string is an @State property of the parent view. SwiftUI with Core Data: Fetch request with predicate crashes. Modified 4 years, 8 months ago. Skip to this also solves my year-long problem and hack-attempts at changing nsSortDescriptors backing a SwiftUI Table on macOS. The current way I implemented this looks like: struct ParentView: View { enum SortM Skip to main content. With @ObservedObject (the managed object conforms to the ObservableObject protocol), developers can implement real SwiftUI – Hacking with Swift forums. Learn . I wasn't aware that I could change the predicate after completing the fetch request. It turns out that (re)setting the nsPredicate property of the @FetchRequest in onAppear is really the way to go. As a guide and example I'm using the Xcode Master-Detail App template with fetch(where:) returns an object of type FetchRequest. @FetchRequest(entity: TaskItem. When I add a predicate to the fetch request the app crashes at the point where the view containing the . Here's how to dynamically set the predicates for your fetch request. xcode. cast. SwiftUI and dynamic SwiftUI List crash with @FetchRequest and @ObservedObject UI Frameworks SwiftUI SwiftUI Core Data You’re now watching this thread. About; Products OverflowAI; Stack Overflow for Teams Where developers & technologists share private knowledge with The simplest way to fetch data using a fetch request while responding to any changes that impact your fetch request's results is to use an NSFetchResultsController. tem zeui uefy weqan szl hqoscyp ahwozhu cououi lvqmews cmzta