Derive default formats for dates and times from user profile language

[VisualAlf]

... and not from app runtime language.

Running the new SampleApp I noticed the 'Dob' and the 'Active At' Columns have the US-Format (12Hour and MM/dd/yyyy). Instead in Germany it should be 24HourClock and Dateformat dd.MM.yyyy

I believe the reason why this happens with the SampleApp but not with my own Apps, is the entry 'Default Language' within Package.appxmanifest. Which is set to 'en_US' in SampleApp, but to 'de-DE' within mine. So it seems, DateTimeFormatter selects the app runtime language.

Instead we should use the user profile language as defined in (win11) Settings > Time & Language > Region & language > Languages. Then the user will automatically see the date/time formats s/he is used to, and not the ones the developer of the app is used to use.

One way to achieve this is to change the default formats in TableViewTimeColumn and in TableViewDateColumn.

• in TableViewTimeColumn.ctor from: ClockIdentifier = DateTimeFormatter.ShortTime.Clock; to: ClockIdentifier = GlobalizationPreferences.Clocks[0];

• in TableViewDateColumn.ctor from: DateFormat = DateTimeFormatter.ShortDate.Patterns[0]; to: DateFormat = new DateTimeFormatter("shortdate", GlobalizationPreferences.Languages).Patterns[0];