title: Flutter FireStore, Get document by Document key
body: <p>Getting a Document by .documents[x]  where x is zero based document number works in this example.  How would I get the Document by a Keyvalue?
  for example, the 3 document would have a key of "qwwe"</p>
  
  <p>how could I get this Document?<br>
  Snapshot.data.document["qwwe"]?</p>
  
  <p>this is the code that is working with the code question code // out.</p>
  
  <pre><code>//=======   this works
  //      body: new ListOfNACS01(),
  
          body: new StreamBuilder(
  //          stream: Firestore.instance.collection('COMPLEX_NONACS').document('A01B01C01D02').snapshots(),
            stream: Firestore.instance.collection('COMPLEX_NONACS').snapshots(),
            builder: (context, snapshot){
              if (!snapshot.hasData) return const Text("---  loading ---");
  //            return new ListView.builder(
  //              itemCount: snapshot.data.document.length,
  //            );
  
                return Column(
                  children: &lt;Widget&gt;[
                    Text(snapshot.data.documents[0].documentID),
                    Text(snapshot.data.documents[0]["DE02PRIMARY"]["INDICATION"]),
  
  
                    //--------  this does not work  ------------
                    //  how to display a document by DocumentID?
  // --  The below line gives error of... 
  // error: Too many positional arguments: 1 expected, but 2 found. 
  // (extra_positional_arguments_could_be_named at [scaiqit55] 
  // lib/main.dart:48).
  
                    Text(snapshot.data.document['A01B01C01D01']),
                    Text(snapshot.data.documents[0]["DE02PRIMARY"]["INDICATION"]),
  
  
                  ],
  
  
                );
            },
          ),
      );
    }
  }
  </code></pre>