backward property Null safety

VoidCallback? backward
read / write

Moves to the previous view programmatically with animation by checking that the previous view dates falls between the minimum and maximum date range.

Note: If the current view has the minimum date range, it will not move to the previous view.

See also:

class MyApp extends StatefulWidget {
 MyAppState createState() => MyAppState();

class MyAppState extends State<MyApp> {
DateRangePickerController _pickerController = DateRangePickerController();

 Widget build(BuildContext context) {
   return MaterialApp(
     home: Scaffold(
       appBar: AppBar(
         actions: <Widget>[
             icon: Icon(Icons.arrow_forward),
             onPressed: () {
         title: Text('Date Range Picker Demo'),
         leading: IconButton(
           icon: Icon(Icons.arrow_back),
           onPressed: () {
       body: SfDateRangePicker(
         controller: _pickerController,
         view: DateRangePickerView.month,
         selectionMode: DateRangePickerSelectionMode.single,


VoidCallback? backward;