在Java Play Framework中使用JQuery更新下拉选择

Question

I want to dynamically add field inputs to a form as the user completes it. However, if the user changes a value for a previous field that others depended on, then I want to hide those later fields again and reset their values back to the default. I can show and hide the input fields without a problem. However, no matter what I do, I cannot change the value of the selection dropdown menu.

Here is my script:

$(function() {
    $('#type_selection').change(function() {
        var case_type = $('#type_selection :selected').val();
        if(case_type !== "") {  //the default value is an empty string
           $('.subtype-panel').slideDown('slow');
        }
        else {
            $('.subtype-panel').slideUp('slow');
            $('#subytype_selection').val("").change();  
        }
    });

});

Play template:

@(caseForm: play.data.Form[Case])

@import views.html.common._
@import models._


@implicitFieldConstructor = @{
    b3.vertical.fieldConstructor
}

@main("New Case Info") {
    <div class="page-header">
        <h3>New Case Information<span class="pull-right label label-primary">Open</span></h3>
    </div>

    <fieldset>
    @b3.form(action = routes.CaseController.save()) {

        <div class="panel panel-primary">
            <div class="panel-heading">Case Type</div>
            <div class="panel-body">

                <div class="row">
                    <div class="col-md-4">
                    @b3.select(caseForm("caseType"),
                        options = options(Case.typeOptions),
                        '_id -> "type_selection",
                        '_label -> "Case Type",
                        '_default -> "-- Select a Type --")
                    </div>
                    <div class="col-md-3">
                    @datePicker(caseForm("date"), '_label -> "Date", 'placeholder -> "mm/dd/yyyy")
                    </div>
                </div>
            </div>
        </div>

        <div class="panel panel-primary subtype-panel">
            <div class="panel-heading">Case Subtype</div>
            <div class="panel-body">
                <div class="row">
                    <div class="col-md-4">
                    @b3.select(caseForm("caseSubType"),
                        options = options(Case.subTypeOptions),
                        '_id -> "subtype_selection",
                        '_label -> "Subtype",
                        '_default -> "-- Select a Subtype --")
                    </div>
                </div>
            </div>
        </div>


    }

    </fieldset>

}

The b3 syntax may look a bit odd to you. It comes from a play bootstrap library: http://adrianhurt.github.io/play-bootstrap/ For b3 select fields, the default option is automatically assigned a value of an empty string. This is what I want to change my selection choice back to using JQuery.

Answer 1

The solution is as adis said in his comment. Using _id -> foo changes the id of the entire form-group (the label and the dropdown), but it does not change the id of the selection box specifically. You have to use id -> foo to do that.