Alligning a DropdownButton in flutter to always be directly under the button

Question

Trying to do a windows themed app and i've been trying to allign the dropdown menu items to behave like like how the windows ones do

Any ideas ?

This is what i want it to look like

Code:

 ///Baudrate
                                    Row(
                                      mainAxisAlignment: MainAxisAlignment.spaceAround,
                                      children: [
                                         Text("BaudRate"),
                                          Align(
                                            alignment: Alignment.centerLeft,
                                            child: Container(
                                              width: 150,
                                              height: 30,
                                              decoration: BoxDecoration(
                                                color: Colors.grey.shade400,
                                                border: Border(
                                                  top: BorderSide(color: Flutter95.grays[0], width: 1),
                                                  left: BorderSide(color: Flutter95.grays[0], width: 1),
                                                  bottom: BorderSide(color: Flutter95.grays[2], width: 3),
                                                  right: BorderSide(color: Flutter95.grays[2], width: 3),
                                                ),
                                              ),
                                              child:Center(
                                              child: DropdownButton(
                                                style: TextStyle(fontSize: 16,color: Colors.black),itemHeight: 50,

                                                value: _selectedBaudrate,
                                                onChanged: (newValue) {setState(() {_selectedBaudrate = newValue.toString();});},
                                                items: _comportBaudrate.map((String item) => DropdownMenuItem<String>(
                                                  value: item,
                                                  child: Text("$item Baud"),
                                                ),).toList(),),
                                                ),
                                            ),
                                          ),