Flutter:get document id form firstore when setData is called

Question

How to get the newly created document id when we call setData

 Future<void> createCommitment() async {
        await widget._firestore
           .collection('skills')
           .document(widget.skillID)
           .collection("commitment")
           .document()
           .setData({
         'bite_id': widget.biteId,
         'start_date': widget.startDate,
         'frequnecy': 3
       });
     }

the current implementation returns void

Solution 1

you have to either set it yourself:

DocumentReference _skillsRef = Firestore.instance.collection('skills').document(skillsID); 

or auto-generate it:

DocumentReference _skillsRef = Firestore.instance.collection('skills').document(); 

and that ref is what you set it on:

_skillsRef.setData({
    'bite_id': widget.biteId,
    'start_date': widget.startDate,
    'frequency': 3
})

Solution 2

Don't use an empty document() or setData, instead seData use add like this :

Future<void> createCommitment() async {
  DocumentReference docRef = await widget._firestore
      .collection('skills')
      .document(widget.skillID)
      .collection("commitment")
      .add({
    'bite_id': widget.biteId,
    'start_date': widget.startDate,
    'frequnecy': 3,
  });
  //Here you have the autogenerated ID :
  print("ID : ${docRef.documentID}");
}