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How to pass DetailView parameters for child entities with CoreData?

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I'm pretty sure this is something very basic but I cannot figure it out.

In my detail view, I use ObservedObjects to define the variables for every child entity, and display them. It works.

Eventually, it asks for me to pass a variable for the each ObservedObject. For the parent entity, I pass the variable defined within the ForEach. For child entities, I tried below approaches:

  • Created separate FetchRequests for each child entity, tried to pass the variables
  • Tried ForEach(zip(sequence1, sequence2, id: \0.self)) { seq1, seq2 in
  • Tried one above without the zip, and just the parent entity

I get the "unable to bla bla, please file a bug report" error in most cases. What am I doing wrong?


ForEach(zip(sequence1, sequence2, id: \0.self)) { seq1, seq2 in

Well, this isn't going to work because you have your parentheses wrong. It should be:

ForEach(zip(sequence1, sequence2), id: \0.self) { seq1, seq2 in

Note that I still don't know if that will do what you want it to do in the larger scope.


Thank you for pointing it out, another head smash for me for today.

I am now getting this now:

The compiler is unable to type-check this expression in reasonable time; try breaking up the expression into distinct sub-expressions

Is it Xcode's fault now? Any ideas on breaking it up further?


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