public function for querying a date's 'selectable' status

[andrewroazen]

The datepicker does not validate against manually entered dates that are blocked out through minDate/maxDate/beforeShowDay. Given the fact that applications are likely to generate datepickers programmatically, it is inconvenient for the developer to independently replicate the data structure and logic already inside ui.datepicker to retrieve a date's status for purposes such as validation.

With one public function, the datepicker object can return a boolean 'selectable' value for any passed date (or default to the current datepicker getDate if none is passed):

	/* Get the selectable status for a date in a jQuery selection.
	   @param  target  element - the target input field or division or span
	   @param  date    Date - the date being queried (defaults to the element's current date)
	   @return selectable - the status */
	_isSelectableDatepicker: function(target,date) {
		date = date || this._getDateDatepicker(target);
		var inst = this._getInst(target);
		if (inst && !inst.inline)
			var minDate = this._getMinMaxDate(inst, 'min', true);
			var maxDate = this._getMinMaxDate(inst, 'max');
			var beforeShowDay = this._get(inst, 'beforeShowDay');
			var daySettings = (beforeShowDay ? beforeShowDay.apply((inst.input ? inst.input[0] : null), [date]) : [true, '']);
			var selectable = !(!daySettings[0] || (minDate !=null && (date < minDate)) || (maxDate !=null && (date > maxDate)));
		return (inst ? selectable : null);
	},

and the argument parser is amended to include this function's name:

if (typeof options == 'string' && (options == 'isDisabled' || options == 'getDate' || options == 'widget' || options == 'isSelectable'))

A sample usage would be as follows:

	jQuery.validator.addMethod("dpicker", function(value, element) {
		selectable = $(element).datepicker("isSelectable");
		return (this.optional(element) || selectable);
	}, "Please choose a valid date");

To query a specific date in a datepicker, the syntax would be:

		selectable = $(element).datepicker("isSelectable",date);

where date is a date object rather than a parseable string (given the utility functions already baked into datepicker, this seems fair).

[andrewroazen]

patched version of jquery.ui.datepicker.js

[andrewroazen]

Also, for the 1.9 version the function would look as follows (if I understand the refactoring correctly):

/* Get the selectable status for a date in a jQuery selection.
   @param  date    Date - the date being queried (defaults to the element's current date)
   @return selectable - the status */
isSelectable: function(date) {
	date = date || this.retrieveDate();
	var minDate = this._get('minDate');
	var maxDate = this._get('maxDate');
	var onDate = this._get('onDate');
	onDate = ($.isFunction(onDate) ? onDate : null);
	var dateInfo = (!onDate ? {} : onDate.apply(this.element[0], [date]));
	var selectable = (dateInfo.selectable == null || dateInfo.selectable) &&
		(!minDate || date.getTime() >= minDate.getTime()) &&
		(!maxDate || date.getTime() <= maxDate.getTime());
	return selectable;
}

[Jörn Zaefferer]

We should make sure that the rewrite takes this into account.

[Scott González]

#7279 is a duplicate of this ticket.

[Scott González]

This is actually not that inconvenient. You're just checking if the date is less than the min, greater than the max, or within your own custom list of dates. Given the lack of requests for this and the relatively simple implementation outside of the datepicker, and the fact that the datepicker would need to invoke a callback related to rendering when not actually rendering, this isn't something we're inclined to implement.