dijit.DateTextBox with dojox.widget.Calendar - initialisation - dojo

Question

Environment: Dojo.1.8.4
If the DateTextBox does not contain a valid date, I wish to start the calendar popup at a date in the past (it's a date of birth entry box). What is the best way of achieving this?
<div maxlength="12"
data-dojo-type="dijit/form/DateTextBox"
data-dojo-props="required: true, constraints:{min:'1880-01-01',
max: new Date()}, popupClass: 'dojox.widget.Calendar'">
</div>
I want to be able to put a 'startDate' parameter or similar in the above such that the constructor for the popup will pick it up and use it.
It looks as though the dojox.widget._CalendarBase sets the date to the current date in its constructor. (actually seems to set it in both the constructor and the declaration).

Answer 1

NOTE: If you are using the dijit/Calendar dropdown default then use the dropDownDefaultValue property as #vogomatix says in the other answer.
The following is if you are using the dojox/widget/Calendar for the dropdown.
By default the popup is set to the current value of the textbox and if null, it will use the current date.
You can do
1) set the value of the text box to what you want the default to be
OR
2) use aspects to set the value in the calendar when it is opened.
require([
'dojo/dom',
'dojo/aspect',
'dijit/form/DateTextBox',
'dojox/widget/Calendar'
], function(dom, aspect, DateTextBox, Calendar){
var dt = new DateTextBox({ popupClass: Calendar }, dom.byId('dtText'));
aspect.after(dt, 'openDropDown', function() {
// only default if there is no value
if(dt.get('value') == null) {
// Do not set the text box when changing value,
// so temporarily override the onchange function
var oldOnChange = dt.dropDown.onChange;
dt.dropDown.onChange = function(){};
dt.dropDown.set('value', new Date(1980, 7, 4)); // default to August 4th, 1980
dt.dropDown.onChange = oldOnChange;
}
});
});
See it in action:
http://jsfiddle.net/cswing/kQYhQ/

Answer 2

One solution is to set dropDownDefaultValue, which works with the standard calendar.
var dt = new DateTextBox({dropDownDefaultValue: new Date( 1950,1,1)},
dom.byId('dtText'));
dropDownDefaultValue gets passed to the calender in the form of currentFocus by the popup. Unfortunately dojox.widget.Calendar does not recognise currentFocus and the way round that is to either extend the class to do so, or to use the aspect method above.

Answer 3

This is how to extend the dojox.widget.Calendar in order to accept the currentFocus passed by the popup. Like the aspect method above, it temporarily disables onChange in order to prevent the value being placed in the parent DateTextBox
define([
"dojo/_base/declare",
"dojox/widget/Calendar"
], function(declare, calendar){
return declare("my.dijit.Calendar", [calendar], {
postCreate: function() {
this.inherited(arguments);
var oldOnChange = this.onChange;
this.onChange = function(){};
this.set('value', this.parseInitialValue( this.currentFocus));
this.onChange = oldOnChange;
}
});
});