[SELECT2] Allow initialization JS overrides

[andruhon]

The JS initialization script was moved from renderHead to Select2Behavior which is burned into the
AbstractSelect2Choice as a private final added in the constructor.

I would add a protected method, something like getSelect2Behavior which would return the select2Behavior, but will allow us to override it (maybe restrict to the Select2Behavior).

The JS inside could also be made customisable. Alternatively the string can be amended without overrides, though Select2Behavior settings.

Currently we have to do some hacking to get rid of default behavior, to add our slightly customized JS:

Optional<? extends Behavior> select2Behavour = getBehaviors().stream().filter(behaviour -> behaviour instanceof Select2Behavior).findFirst();
       if (select2Behavour.isPresent()) {
           remove(select2Behavour.get());
       }

[solomax]

The functionality you are requesting is already implemented :)

You can override JS/CSS scripts
Please take a look at ApplicationSettings class

:)

[andruhon]

Thank you @solomax ! The intent is not to replace the JS file reference, but to change this string: "$('#%s').select2(%s);"

[solomax]

So you would like select2 drop-down will not be select2?
Maybe you can provide sort of real-life-example?

[andruhon]

@solomax Kind of. Unfortunately some things are not available through options and it's needed to "override" the constructor like this:

    $.fn.select2.amd.define("select2/myMagicSelect2",
            ['select2/core'],
            function (Select2) {
                return function ($el, options) {
                    // my magic stuff
                    var select = new Select2($el, options);
                    // more magic stuff
                }
            }
    );

and later call something like

$.fn.select2.amd.require('select2/myMagicSelect2')($select, options);

So the $.fn.select2.amd.require('select2/myMagicSelect2')($('#%s'), %s) would replace $('#%s').select2(%s);

[solomax]

I believe you can create PR :)

[andruhon]

I will

[andruhon]

@solomax is JIRA also needed?

[solomax]

@andruhon no JIRA is required, this is not part of Apache Wicket :)

[solomax]

@andruhon I believe the easiest way to implement this will be one more setting in ApplicationSettings class :)