Adding the possibility to specify the initial date selected in the date picker dialog.

lib/src/field.dart

@@ -22,6 +22,7 @@ class DateTimeField extends StatelessWidget {
     this.mode = DateTimeFieldPickerMode.dateAndTime,
     this.initialEntryMode = DatePickerEntryMode.calendar,
     this.dateTextStyle,
+    this.initialDate,
     DateTime? firstDate,
     DateTime? lastDate,
     DateFormat? dateFormat,
@@ -36,6 +37,7 @@ class DateTimeField extends StatelessWidget {
     this.selectedDate,
     this.decoration,
     this.enabled,
+    this.initialDate,
     this.dateTextStyle,
     this.initialEntryMode = DatePickerEntryMode.calendar,
     DateTime? firstDate,
@@ -59,6 +61,9 @@ class DateTimeField extends StatelessWidget {
   /// The last date that the user can select (default is 2100)
   final DateTime lastDate;
 
+  /// The date that will be selected by default in the calendar view.
+  final DateTime? initialDate;
+
   /// Let you choose the [DatePickerMode] for the date picker! (default is [DatePickerMode.day]
   final DatePickerMode? initialDatePickerMode;
 
@@ -82,7 +87,18 @@ class DateTimeField extends StatelessWidget {
 
   /// Shows a dialog asking the user to pick a date !
   Future<void> _selectDate(BuildContext context) async {
-    final DateTime initialDateTime = selectedDate ?? DateTime.now();
+    final DateTime initialDateTime;
+
+    if (selectedDate != null) {
+      initialDateTime = selectedDate!;
+    } else {
+      final DateTime now = DateTime.now();
+      if (firstDate.isAfter(now) || lastDate.isBefore(now)) {
+        initialDateTime = initialDate ?? lastDate;
+      } else {
+        initialDateTime = now;
+      }
+    }
 
     if (Theme.of(context).platform == TargetPlatform.iOS) {
       showModalBottomSheet<void>(

lib/src/form_field.dart

@@ -24,6 +24,7 @@ class DateTimeFormField extends FormField<DateTime> {
     DateFormat? dateFormat,
     DateTime? firstDate,
     DateTime? lastDate,
+    DateTime? initialDate,
     ValueChanged<DateTime>? onDateSelected,
     InputDecoration? decoration,
     DatePickerEntryMode initialEntryMode = DatePickerEntryMode.calendar,
@@ -54,6 +55,7 @@ class DateTimeFormField extends FormField<DateTime> {
 
             return DateTimeField(
               firstDate: firstDate,
+              initialDate: initialDate,
               lastDate: lastDate,
               decoration: effectiveDecoration,
               initialDatePickerMode: initialDatePickerMode,