next method
void
next()
Implementation
void next() {
var index = ThemeMode.values.indexOf(state);
state = ThemeMode.values[(index + 1) % ThemeMode.values.length];
ref.notifyListeners();
}
void next() {
var index = ThemeMode.values.indexOf(state);
state = ThemeMode.values[(index + 1) % ThemeMode.values.length];
ref.notifyListeners();
}