title: Bottom Naviagtion Bar not hidden after pushed to new screen
body: <p>I have two screen A and B, screen A has a bottom navigation bar. </p>
  
  <p>After i pushed screen A to screen B, bottom navigation bar of screen A still pin on screen B. </p>
  
  <p>I want show full screen B without bottom navigation of screen A.</p>
  
  <p>This is a screen A, it has a bottom naviagtion bar:</p>
  
  <pre><code>class Parent extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return MaterialApp(
        title: 'TechOne',
        theme: ThemeData(
          primarySwatch: Colors.red,
        ),
        home: MyParentPage(title: 'TechOne'),
      );
    }
  }
  
  /*StatefulWidget is Widget with mutable*/
  class MyParentPage extends StatefulWidget {
    MyParentPage({Key key, this.title}) : super(key: key);
  
    final String title;
  
    @override
    _MyParentPageState createState() =&gt; _MyParentPageState();
  }
  
  /*State is a manager of StatefulWidget*/
  class _MyParentPageState extends State&lt;MyParentPage&gt;
      with SingleTickerProviderStateMixin {
    var _itemSelected = 0;
    TabController _tabController;
  
    final _bodyUI = [
      HomeUI(),
      SearchUI(),
      Center(
        child: Text('Notification'),
      ),
      Center(
        child: Text('Account'),
      ),
    ];
  
    _onBottomNavigationBarTap(int index) {
      print(_itemSelected);
      setState(() {
        _itemSelected = index;
      });
    }
  
    @override
    void initState() {
      // TODO: implement initState
      super.initState();
      _tabController = TabController(length: 4, vsync: this);
    }
  
    @override
    Widget build(BuildContext context) {
      _tabController.animateTo(_itemSelected);
  
      return Scaffold(
          bottomNavigationBar: BottomNavigationBar(
            items: Values.itemsBottomNavigationBar,
            onTap: (index) {
              _onBottomNavigationBarTap(index);
            },
            currentIndex: _itemSelected,
            selectedItemColor: Colors.red,
            backgroundColor: Colors.white,
            type: BottomNavigationBarType.fixed,
          ),
          body: TabBarView(
              physics: NeverScrollableScrollPhysics(),
              controller: _tabController,
              children: &lt;Widget&gt;[
                _bodyUI[0],
                _bodyUI[0],
                _bodyUI[2],
                _bodyUI[3],
              ]));
    }
  }
  </code></pre>
  
  <p>Inside _bodyUI[0] widget, I push to screen B:</p>
  
  <pre><code>Navigator.push(context, MaterialPageRoute(builder: (context) =&gt; SearchUI()));
  </code></pre>
  
  <p>This is a screen B, bottom navigation bar still pin on here, i want hidden it:</p>
  
  <pre><code>class SearchUI extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      // TODO: implement build
      return MaterialApp(
        title: 'Search',
        theme: ThemeData(primarySwatch: Colors.red),
        home: MySearchPage(),
      );
    }
  }
  
  class MySearchPage extends StatefulWidget {
    @override
    State&lt;StatefulWidget&gt; createState() {
      // TODO: implement createState
      return _MySearchState();
    }
  }
  
  class _MySearchState extends State&lt;MySearchPage&gt; {
    final TextEditingController _textEditingController = TextEditingController();
    final FocusNode _focusNode = FocusNode();
  
    TextField _appBarTitle;
  
    @override
    void initState() {
      // TODO: implement initState
      super.initState();
  
      _appBarTitle = TextField(
          controller: _textEditingController,
          focusNode: _focusNode,
          autofocus: true,
          textInputAction: TextInputAction.done,
          textCapitalization: TextCapitalization.sentences,
          cursorColor: Colors.white,
          cursorRadius: Radius.circular(16),
          maxLines: 1,
          style: TextStyle(
            color: Colors.white,
          ),
          decoration: InputDecoration(
              border: InputBorder.none,
              prefixIcon: Icon(
                Icons.search,
                color: Colors.white,
              ),
              suffixIcon: IconButton(icon: Icon(Icons.clear, color: Colors.white,), onPressed: (){
                _textEditingController.clear();
              }),
              hintText: 'Search...',
              hintStyle:
                  TextStyle(color: Colors.white.withOpacity(0.5), fontSize: 18)));
    }
  
    @override
    Widget build(BuildContext context) {
      // TODO: implement build
      return Scaffold(
        appBar: AppBar(
          title: _appBarTitle,
        ),
        body: Center(
          child: Text('Search Screen'),
        ),
      );
    }
  }
  </code></pre>