title: How do use navigator.push to navigate to a specific tab
body: <p>Let's assume I want to navigate to a specific tab, for example to the tab 'Chats' which view is defined in ChatsOverview(). Each tab does not have its own Scaffold / Material widget. It directly returns a StreamBuilder, so navigator.push is not directly working? </p>
  
  <pre><code>Widget build(BuildContext context) {
      return WillPopScope(
        onWillPop: () =&gt; Future.value(false),
        child: new Scaffold(
            appBar: AppBar(
                leading: Container(), 
                flexibleSpace: SafeArea(
                    child: new TabBar(indicatorWeight: 4.0,indicatorColor: Colors.white, controller: controller, tabs: &lt;Tab&gt;[
                  new Tab(
                    text: 'Gruppen',
                    icon: Icon(Icons.group),
                  ),
                  new Tab(
                    text: 'Chats',
                    icon: Icon(Icons.chat_bubble),
                  ),
                  new Tab(
                    text: 'Einstellungen',
                    icon: Icon(Icons.settings),
                  )
                ]))),
            body: new TabBarView(controller: controller, children: &lt;Widget&gt;[
              new first.GroupsOverview(),
              new second.ChatsOverview(),
              new third.Settings()
            ])),
      );
    }
  </code></pre>