I need your help. I'm making a DropdownButton and I'm facing the following problem - I can't see the items that are selected in the DropdownMenuItems. I do not understand what the problem is that nothing is displayed. I'm using the

CodePudding user response：

While the UI is need to update on DropdownMenuItem you can wrap GFCheckboxListTile with StatefulBuilder.

child: Container(
  child: StatefulBuilder(
    builder: (context, setStateSB) => GFCheckboxListTile(
      value: _selectedTitles.contains(widget.items[index]),
      onChanged: (bool selected) {
        _onItemSelect(selected, index);
        setStateSB(() {}); /// we are using StatefulBuilder's setState

       ///add your logic then 
  setState(() {
    selectedValue = widget.items[index];
  });
      },

DropdownMenuItem ontap is outSide the GFCheckboxListTile therefore onChanged is not calling. I am using onChanged from GFCheckboxListTile to update the selectedValue.