(GH-3746) Fix Date and Time selection and other improvements for DateTimePicker

[timunie]

Describe the changes you have made to improve this project

• Fix input for date and time text input for DateTimePicker
  • if the Time is selected before a Date is selected use DateTime.Today instead of DateTime.Min
  • If a new Value is selected from the Calendar we use the already Selected time.
• Use PopupEx to fix position change for floating watermark
• Fix wrong focus for popup content
• Fix closing (unfocusing) and opening PopUp
• Fix capturing CalendarItem
• Add key processing if Popup is open
• Add DisplayDateChanged event handling
• Respect IsEnabledProperty
• Remove TimePickerBaseSelectionChangedEventArgs and use RoutedPropertyChangedEventHandler and RoutedPropertyChangedEventArgs
• Set selected date and time from textbox

Unit test

DateTimePickerTests

Additional context

There is one issue left where I have no idea how to solve this: If the user inserts a new DateTime manually where the time is 00:00:00 the time might get overridden with the last used time. I think this case is rather rare, but should be considered anyway.

Closed Issues

Closes #3746

[timunie]

@punker76 can we change TimePickerBaseSelectionChangedEventArgs to GenericSelectionChangedEventArgs? We then could reuse it e.g. for the ColorPicker. It is already generic, just the name does not say it :-)

Have a great day
Tim

[punker76]

@punker76 can we change TimePickerBaseSelectionChangedEventArgs to GenericSelectionChangedEventArgs? We then could reuse it e.g. for the ColorPicker. It is already generic, just the name does not say it :-)

Have a great day
Tim

@timunie You can use the RoutedPropertyChangedEventHandler and RoutedPropertyChangedEventArgs which are generic classes. I removed the TimePickerBaseSelectionChangedEventArgs because we don't need them.

[timunie]

Thank you for the info. I wil use this instead