@Published property wrapper not working on subclass of ObservableObject

Finally figured out a solution/workaround to this issue. If you remove the property wrapper from the subclass, and call the baseclass objectWillChange.send() on the variable the state is updated properly.

NOTE: Do not redeclare let objectWillChange = PassthroughSubject<Void, Never>() on the subclass as that will again cause the state not to update properly.

I hope this is something that will be fixed in future releases as the objectWillChange.send() is a lot of boilerplate to maintain.

Here is a fully working example:

    import SwiftUI    class MyTestObject: ObservableObject {        @Published var aString: String = ""    }    class MyInheritedObject: MyTestObject {        // Using @Published doesn't work on a subclass        // @Published var anotherString: String = ""        // If you add the following to the subclass updating the state also doesn't work properly        // let objectWillChange = PassthroughSubject<Void, Never>()        // But if you update the value you want to maintain state         // of using the objectWillChange.send() method provided by the         // baseclass the state gets updated properly... Jaayy!        var anotherString: String = "" {            willSet { self.objectWillChange.send() }        }    }    struct MyTestView: View {        @ObservedObject var myTestObject = MyTestObject()        @ObservedObject var myInheritedObject = MyInheritedObject()        var body: some View {            NavigationView {                VStack(alignment: .leading) {                    TextField("Update aString", text: self.$myTestObject.aString)                    Text("Value of aString is: \(self.myTestObject.aString)")                    TextField("Update anotherString", text: self.$myInheritedObject.anotherString)                    Text("Value of anotherString is: \(self.myInheritedObject.anotherString)")                }            }        }    }

iOS 14.5 resolves this issue.

Combine

Resolved Issues

Using Published in a subclass of a type conforming to ObservableObject now correctly publishes changes. (71816443)

This is because ObservableObject is a protocol, so your subclass must conform to the protocol, not your parent class

Example:

class MyTestObject {    @Published var aString: String = ""}final class MyInheritedObject: MyTestObject, ObservableObject {    @Published var anotherString: String = ""}

Now, @Published properties for both class and subclass will trigger view events