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Ultimate Portfolio App - View Modifier for Previews idea

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So I've started Paul's new Ultimate Portfolio App series.

Really enjoying the series so far. After finishing the "First steps in UI" article I realized that copying the code to add the DataController and CoreData each time would become repetative and cumbersome.

To make working with Previews a little more "DRY," I created a custom view modifier to add all of the DataController code. So far this seems to be working effectively. Let me know what you all think.

struct PreviewDataInjector: ViewModifier {
    let dataController = DataController.preview

    func body(content: Content) -> some View {
            .environment(\.managedObjectContext, dataController.container.viewContext)

extension View {
    func previewDataController() -> some View {

Then you can just use the view modifier to eliminate the boiler plate on previews.

struct ProjectsView_Previews: PreviewProvider {
    static var previews: some View {
        ProjectsView(showClosedProjects: false)


Nice but you will need to add


around the struct and extension as Previews are only on Debug not Release



Great point!


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