When we edit an Entity which has one or more Date or DateTime attributes , RichWidgets\Input_Calendar is placed near by the Input Widget.
The format of this Input Widget equals to 'Date format' configured in service center('YYYY-MM-DD' by default).
I'd like to change this format for each locale, and set Input_Calendar.DateFormat property as below.
If(GetCurrentLocale() = "ja-JP", "%Y/%m/%d", "%b %e, %Y")
And my locale was set to "ja-JP" by using Action:SetCurrentLocale().
When I opened my WebScreen on which can edit the Entity, the format of date field was still 'YYYY-MM-DD'.
And when I changed the date field value by using Input_Calendar, the format of date field was changed to 'YYYY/MM/DD'.
And when I pressed the save button to save this change, the validation error was caused(Date expected!).
Considering these fact, I think there is little point in Input_Calendar.DateFormat property.
I suggest making a clear distinction between System Format(configured in service center) and Display Format(Input_Calendar.DateFormat) , improving above behavior.
With respect to (1), it's better to apply 'YYYY/MM/DD' format to Input Widget from the beginning.
With respect to (3), it's better not to cause the validation error and to save changes normally.