title: Flutter how to create List view autoscrolling?
body: <p>I'm trying to make a ListView that auto-scrolls to the newest data point. 
  I tired to do this by making a _scrollToBottom function that uses the .jumpTo method.</p>
  
  <p>But i get a blank screen in the app, and 
  <code>'child.parentData != null': is not true.</code> in the debug console.</p>
  
  <p>Any suggestions on how i can implement auto-scrolling?</p>
  
  <p>Here is the relevant portions of my current code:</p>
  
  <pre><code>ScrollController _scrollController = ScrollController();
  
  _scrollToBottom(){  _scrollController.jumpTo(_scrollController.position.maxScrollExtent);
  }
  
  @override
    Widget build(BuildContext context) {
      return StreamBuilder(
        stream: DataShareWidget.of(context).stream,
        builder: (BuildContext context, AsyncSnapshot snapshot){
          if(snapshot.hasError){ return Text(snapshot.error);}
          if(snapshot.hasData){
            _dataFormat(snapshot.data);
            return ListView.builder(
              itemCount: _listViewData.length,
              controller: _scrollController,
              reverse: true,
              shrinkWrap: true,
              itemBuilder: (context, index) {
                _scrollToBottom();
                return ListTile(
                  title: AutoSizeText(_listViewData[index], maxLines: 2),
                  dense: true,
                );
              },
            );
          }
        }
      );
    }
  </code></pre>