Support for Hijri or Jalali or other international calendar in datepicker

[araselahi]

I think making dateUtil.js injectable, would provide calendar support functionality for Hijri or Jalali or other international calendars in datepicker. Adding fromGregorian and toGregorian date functions to $mdDateLocale service may provide more abstract solution. These functions could be consequently used in dateUtil.js to provide localized date calculation. Currently $mdDateLocale just provide messages, formatters, and parsers for date internationalization but not date conversion.

I volunteer to produce dateUtil or $mdDateLocale for Hijri or Jalali. Please help me how.

[fxck]

There's no datepicker in material2. $mdDateLocale sounds like material. You are probably in a wrong repo.

[araselahi]

I just saw datepicker on material2 feature status: https://github.com/angular/material2#feature-status
thought that it would inherit the same functionality from material. Hope you take internationalization date conversion into account for new datepicker. We all love material(2) and your great project.

[fxck]

The problem with datepicker, as mentioned in its issue, is that there are no specs(for desktop version anyway) in material design for it.. so until google designers create those, there won't be no official date/timepicker implementation. Sadly.

But I'm pretty sure that once the spec is done, internationalization will be taken into account.

[araselahi]

Internationalization date conversion may not affect visual design of datepicker. It just refer to how cells arrange according to the native calendar rules, mainly the same functions as currently exist in dateUtil, but with native alternative principals. About the visual customization, task already has been done gracefully in $mdDateLocale.

[jelbourn]

We're designing the datepicker now. We likely will only be able to support the Gregorian calendar in the initial version, but it's worth thinking about in the design.

[araselahi]

At the moment it may not important to support any special native calendar. The important point about this feature is to make the logic of date conversion 'injectable'. Then every folk will know how to implement their native conversion logic providers. Although I had some suggestions above, but as a designer, you know better how to construct the structure. Thanks Jeremy, for taking it into account and for your grate project.

[mmalerba]

I'll have a design doc to share shortly, it would be great if you could take a look and let me know if you think the design is flexible enough to support this.

[araselahi]

of course, it would be my pleasure.

[mmalerba]

@araselahi design doc is now available: https://docs.google.com/document/d/1RwPFESCbSSLMSDqxWo7jg4UUpGJTrXX6p5wYlb9pmNc/preview

[araselahi]

I have just seen the notification in my email. I will get back to you soon.

[araselahi]

@mmalerba 'CalendarLocale injectable' and 'Internationalization' sections currently include the definition only about the word translation and visual parsing and formatting but not other nationality date conversion logic. In other calendars, days calculation completely different from Gregorian. So I guess we need all the logic in dateUtil.js such as getFirstDateOfMonth, getNumberOfDaysInMonth and so on could be replaceable according to the other international calendar to determine how the days to be rendered on date picker. I think with this suggested feature, it would be a magic date picker for other folks. I am not sure the new SimpleDate data type could support other international calendar date because it is still subset of Gregorian calendar date. Am I right?