Dragging bottom bar does not work

[Sun3]

Using the sample code provided by this repo when you try to drag the bottom bar up or down it does not move. Is there a setting to change?

Thanks

[ederjavs]

the secret is the controller

class _MyScreenState extends State<MyScreen> with SingleTickerProviderStateMixin {
BottomBarController controlador;

......

@OverRide
void initState() {
super.initState();
controlador = BottomBarController(vsync: this, dragLength: 450, snap: true);
}

floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
floatingActionButton: GestureDetector(
// Set onVerticalDrag event to drag handlers of controller for swipe effect
onVerticalDragUpdate: controlador.onDrag,
onVerticalDragEnd: controlador.onDragEnd,
child: FloatingActionButton.extended(
heroTag: null,
label: Text("Pull up"),
elevation: 2,
backgroundColor: Colors.deepOrange,
foregroundColor: Colors.white,

      //Set onPressed event to swap state of bottom bar
      onPressed: () {
        print("object");
        controlador.swap();
      },
    ),
  ),
  bottomNavigationBar: BottomExpandableAppBar(
    controller: controlador,
    expandedHeight: 550,
    horizontalMargin: 16,
    shape: AutomaticNotchedShape(
        RoundedRectangleBorder(), StadiumBorder(side: BorderSide())),
    expandedBackColor: Colors.white,
    expandedBody: Center(
      child: Text("Hello world!"),
    ),
    bottomAppBarBody: Padding(
      padding: const EdgeInsets.all(8.0),
      child: Row(
        mainAxisSize: MainAxisSize.max,
        children: <Widget>[
          Expanded(
            child: Text(
              "Tets",
              textAlign: TextAlign.center,
            ),
          ),
          Spacer(
            flex: 2,
          ),
          Expanded(
            child: Text(
              "Stet",
              textAlign: TextAlign.center,
            ),
          ),
        ],
      ),
    ),
  ),