How can I clear dropdown selection? - flutter

Question

I'm using the dropdown_button2 package on the project that I'm currently working on. Everything works fine but I need to clear the selection with a cancel button and I can't reach the selected value.
Here is my code:
final TextEditingController _searchController = TextEditingController();
bool _doctorSelection = false;
DropdownButtonHideUnderline(
child: DropdownButtonFormField2<String>(
items: _doctorList
.map((item) => DropdownMenuItem(
value: item,
child: Text(
item,
style: const TextStyle(
fontSize: 14,
),
),
))
.toList(),
searchController: _searchController,
searchInnerWidget: TextFormField(
controller: _searchController,
textAlignVertical: TextAlignVertical.center,
decoration: const InputDecoration(
hintText: 'Doktor Adı',
hintStyle: TextStyle(
fontSize: 14,
),
suffixIcon: Icon(Icons.search),
contentPadding: EdgeInsets.only(left: 15),
),
),
searchMatchFn: (a, searchValue) {
return a.value
.toString()
.toLowerCase()
.contains(searchValue.toLowerCase());
},
onChanged: (value) {
setState(() {
_doctorSelection = true;
});
},
onMenuStateChange: (isOpen) {
if (!isOpen) {
_searchController.clear();
}
},
decoration: const InputDecoration(
isDense: true,
contentPadding: EdgeInsets.zero,
border: InputBorder.none,
icon: Padding(
padding: EdgeInsets.only(left: 15.0),
child: Icon(
Icons.person,
),
),
),
buttonPadding: const EdgeInsets.only(
right: 15,
),
buttonHeight: 45,
isExpanded: true,
dropdownMaxHeight: 240,
dropdownWidth: screenWidth,
dropdownDecoration: BoxDecoration(
border: Border.all(
color: Colors.grey.shade400,
),
borderRadius: const BorderRadius.only(
bottomLeft: Radius.circular(12),
bottomRight: Radius.circular(12),
),
),
scrollbarAlwaysShow: true,
alignment: Alignment.centerLeft,
hint: const Text(
"Doktor Ara",
style: TextStyle(fontSize: 14, color: Colors.grey),
),
icon: _doctorSelection
? GestureDetector(
onTap: () {
setState(() {
_doctorSelection = false;
});
},
child: const Icon(
Icons.cancel,
color: Colors.red,
),
)
: Icon(
Icons.keyboard_arrow_down,
color: Colors.blueGrey[400],
),
),
)
What I want to achieve is to clear the selection with the cancel button and show the hint text again.
I tried to clear _searchController but nothing happened. My guess is, I should manipulate the value in DropdownMenuItem widget but I don't know how.