why Doesn't see List type?

I am using declare an array –

  final List<DropdownMenuItem<String>> listDropDown;

And I use the following construction –

class DropDown extends StatelessWidget {

  final String dropDownValue;
  final List<DropdownMenuItem<String>> listDropDown;

  DropDown(this.dropDownValue, this.listDropDown);

But I get an error –

The argument type 'List<dynamic>' can't be assigned to the parameter type 'List<DropdownMenuItem<String>>?'.

In this place –

return DropdownMenuItem(
                      value: dropDownValue,
                      child: Text(items, style: TextStyle(fontFamily: "Mark-Pro", fontSize: 18, fontWeight: FontWeight.w500, color: configColors.darkBlue),),
                    );
                  }).toList(),

full dropDownButtom –

child: DropdownButton(
                  items: listDropDown.map((String items) {
                    return DropdownMenuItem(
                      value: dropDownValue,
                      child: Text(items, style: TextStyle(fontFamily: "Mark-Pro", fontSize: 18, fontWeight: FontWeight.w500, color: configColors.darkBlue),),
                    );
                  }).toList(),
                  // Initial Value
                  value: dropDownValue,

                  // Down Arrow Icon
                  icon: const Icon(Icons.keyboard_arrow_down),

                  // Array list of items

                  // After selecting the desired option,it will
                  // change button value to selected value
                  onChanged: (String? newValue) {
                    mystate(() {
                      dropDownValue = newValue!;
                    });
                  },
                ),

>Solution :

The issue is in calling DropDown, you are passing List instead of List<DropdownMenuItem> to DropDown’s listDropDown.

try this:

DropdownButton<String>(
                  items: listDropDown.map((String items) {
                    return DropdownMenuItem<String>(
                      value: dropDownValue,
                      child: Text(items, style: TextStyle(fontFamily: "Mark-Pro", fontSize: 18, fontWeight: FontWeight.w500, color: configColors.darkBlue),),
                    );
                  }).toList(),
                  // Initial Value
                  value: dropDownValue,

                  
                  icon: const Icon(Icons.keyboard_arrow_down),
                  onChanged: (String? newValue) {
                    mystate(() {
                      dropDownValue = newValue!;
                    });
                  },
                )