Drop down button in flutter not switching values to the selected value

Question

I\'ve recently started programming using dart and flutter and everything has been going smoothly for my app, although recently i wanted to add drop down menu to provide the user

Answer 1

The error is because you are declaring a method variable newValue you must declare that variable as global inside your StatefulWidget.

   String newValue;

  Widget buildDropdownButton() {
  return new Padding(
    padding: const EdgeInsets.all(24.0),
    child: new Column(
      mainAxisAlignment: MainAxisAlignment.start,
      children: [
        new ListTile(
          title: const Text('Frosting'),
          trailing: new DropdownButton(
              hint: Text('Choose'),
              onChanged: (String changedValue) {
                newValue=changedValue;
                setState(() {
                  newValue;
                  print(newValue);
                });
              },
              value: newValue,
              items: ['None', 'Chocolate', 'Vanilla', 'ButterCream']
                  .map((String value) {
                return new DropdownMenuItem(
                  value: value,
                  child: new Text(value),
                );
              }).toList()),
        ),
      ],
    ),
  );
  }