title: how to get data from cloud firestore where user.uid equal to document id in flutter?
body: <p>I am Having this profile screen which shows users info.
  after user authenticated I am storing data in cloud firestore with document id is equal to user-id.
  Now, I want to retrieve data from cloud firestore with having current userId is equal to document id.</p>
  
  <p><a href="https://i.stack.imgur.com/pBQfx.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pBQfx.png" alt="enter image description here"></a></p>
  
  <p>For now i have this :</p>
  
  <pre><code>class UserManagement {
    getData() async{
      String userId = (await FirebaseAuth.instance.currentUser()).uid;
      print(userId);
      return Firestore.instance.collection('users').document(userId);
  
    }
  </code></pre>
  
  <p>but this is not working properlywhen i log out and after re-login with different user it showing me same data.</p>
  
  <pre><code>UserManagement().getData().then((results) {
      setState(() {
        userFlag = true;
         users = results;
      });
      });
  </code></pre>
  
  <p>Now, how get other fields like name,email,course,phonenumber..etc
  and all values all storing into user.right?</p>