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ViewModel doesn't reach the sheetView when using @EnvironmentObject

Forums > SwiftUI

I'm building an app and run into some problems. If I want to access data from a tabView it's no problem. Also a linked view is no problem, but I can't access the viewModel in a sheet.

I have an addView(sheet) that has a some entry fields. When the user hits the save button the data is saved to coreData with a function in the ViewModel. Also in the ViewModel is a function to connect two coreData entities to eachother (think company and employee). But this function doesn't work in the sheet by using the same save-button. It looks like the arrays aren't passed.

To make the ViewModel available in every tabView i used:

@StateObject private var vm: CoreDataViewModel = CoreDataViewModel() 

in the contentView and on every tabItem:

.environmentObject(vm) 

Then everywhere the vm is needed i used:

@EnvironmentObject var vm: CoreDataViewModel

   

So accoording to you adding Codable conformance for @Published properties should solve the problem?

   

hi,

unless something's changed recently ... i'm not into iOS 16 and SwiftUI 4 stuff yet ... a sheet does not inherit the environment of the view that creates it.

  • in your .sheet modifier, consider injecting the view model directly into the environment of the view that is opened.

    .sheet(isPresented: $isPresented) {
    AddView()
        .environmentObject(vm)
    }
  • alternatively, you could pass the view model directly as an argument, where the viewModel variable in the AddView is marked as an @ObservedObject.

    .sheet(isPresented: $isPresented) {
    AddView(viewModel: vm)
    }

hope that helps,

DMG

   

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