Action after deleting a row

[StewartLynch]

In my model where I have this

@Observable
class PropertiesListModel {
    @ObservationIgnored
    @Dependency(\.defaultDatabase) var database
    @ObservationIgnored
    @FetchAll(Property.order(by: \.name)) var properties
   
    var selectedProperty: Property?
.....
}

I have this function that is called when I delete a row.
The only way I can get the selectedProperty to update is if I have this short sleep in the function otherwise it does not update as shown. It works perfectly, but I can’t be doing this the correct way. if else clause needs to wait until the deletion is complete.
Pardon my SQL ignorance here.

func deletePropertyButtonTapped(property: Property) {
    withErrorReporting {
        try database.write { db in
            try Property
                .delete(property)
                .execute(db)
            Task {
                try await Task.sleep(for: .seconds(0.05))
                self.selectedProperty = self.properties.first
            }
        }
    }
}

[mbrandonw]

Hi @StewartLynch, the @FetchAll property subscribes to changes in the database so that when data changes the state updates automatically. However, "automatically" does not mean synchronously and immediately. It does take a few moments for the subscription to be notified and the state to be updated. That is why you are needing to sleep for a few milliseconds before properties has the correct value.

But, you can force the state held in @FetchAll to immediately load the freshest data from the database. There's a load() method on the projected value of @FetchAll that does this, and your example can be updated like this:

func deletePropertyButtonTapped(property: Property) async {
  await withErrorReporting {
    try await database.write { db in
      try Property
        .delete(property)
        .execute(db)
      }
    try await $properties.load()
    self.selectedProperty = self.properties.first
  }
}

Note that deletePropertyButtonTapped had to be made async, and so you can push the unstructured Task { … } to the view instead of your model. That keeps your model more easily testable. And after the $properties.load() you can be sure that properties has the freshest data, and so then properties.first should work just fine.

[StewartLynch]

Perfect again. Much appreciated. That was my last issue so far. On to more. By the way, the reason why I have a selectedProperty is because I am using a Picker to display the information for a selected Property