anchor.diff:    /// Whether to use 24 hour format. Defaults to false.
     final bool use24hFormat;
   
  -  /// Callback called when the selected date and/or time changes. If the new selected
  -  /// [DateTime] is not valid, or is not in the [minimumDate] through [maximumDate]
  -  /// range, this callback will not be called.
  +  /// Callback called when the selected date and/or time changes. If the new
  +  /// selected [DateTime] is not valid, or is not in the [minimumDate] through
  +  /// [maximumDate] range, this callback will not be called.
     ///
     /// Must not be null.
     final ValueChanged<DateTime> onDateTimeChanged;
  
positive.code:   /// the intervals set in [minimumDate], [maximumDate], [minimumYear], and
    /// [maximumYear].
    ///
    /// [minimumDate] is the minimum [DateTime] that the picker can be scrolled to.
    /// Null if there's no limit. In [CupertinoDatePickerMode.time] mode, if the
    /// date part of [initialDateTime] is after that of the [minimumDate], [minimumDate]
    /// has no effect.
    ///
    /// [maximumDate] is the maximum [DateTime] that the picker can be scrolled to.
    /// Null if there's no limit. In [CupertinoDatePickerMode.time] mode, if the
    /// date part of [initialDateTime] is before that of the [maximumDate], [maximumDate]
    /// has no effect.
    ///
    /// [minimumYear] is the minimum year that the picker can be scrolled to in
    /// [CupertinoDatePickerMode.date] mode. Defaults to 1 and must not be null.
  
negative.code:   /// selected date time.
    final DateTime initialDateTime;
  
    /// The minimum selectable date that the picker can settle on.
    ///
    /// When non-null, the user can still scroll the picker to [DateTime]s earlier
    /// than [minimumDate], but the [onDateChangeCallback] will not be called on
    /// these [DateTime]s. Once let go, the picker will scroll back to [minimumDate].
    ///
    /// In [CupertinoDatePickerMode.time] mode, a time becomes unselectable if the
    /// [DateTime] produced by combining that particular time and the date part of
    /// [initialDateTime] is earlier than [minimumDate]. So typically [minimumDate]
    /// needs to be set to a [DateTime] that is on the same date as [initialDateTime].
    ///
    /// Defaults to null. When set to null, the picker does not impose a limit on
    /// the earliest [DateTime] the user can select.
    final DateTime minimumDate;
  
    /// The maximum selectable date that the picker can settle on.
    ///
    /// When non-null, the user can still scroll the picker to [DateTime]s later
    /// than [maximumDate], but the [onDateChangeCallback] will not be called on
    /// these [DateTime]s. Once let go, the picker will scroll back to [maximumDate].
    ///
    /// In [CupertinoDatePickerMode.time] mode, a time becomes unselectable if the
    /// [DateTime] produced by combining that particular time and the date part of
    /// [initialDateTime] is later than [maximumDate]. So typically [maximumDate]
    /// needs to be set to a [DateTime] that is on the same date as [initialDateTime].
    ///
    /// Defaults to null. When set to null, the picker does not impose a limit on
    /// the latest [DateTime] the user can select.
    final DateTime maximumDate;
  
    /// Minimum year that the picker can be scrolled to in
  