drawer.dart

Widget _createHeader() {
    return DrawerHeader(
        margin: EdgeInsets.zero,
        padding: EdgeInsets.zero,
        decoration: BoxDecoration(
            image: DecorationImage(
                fit: BoxFit.fill,
                image: AssetImage('res/images/drawer_header_background.png'))),
        child: Stack(children: <Widget>[
          Positioned(
              bottom: 12.0,
              left: 16.0,
              child: Text("Flutter Step-by-Step",
                  style: TextStyle(
                      color: Colors.white,
                      fontSize: 20.0,
                      fontWeight: FontWeight.w500))),
        ]));
  }