Question

I’m using checkboxes to toggle the enabled and disabled state of some multi-lists on a registration form. The checkbox is labeled with the category, and the multi-list contains the items that belong to that category.

I’m using jQuery 1.7.2.

        $('#sch_cat_hockeyschools').toggle(function(ev) {
                ev.stopPropagation();
                $("#type_select_hockeyschools").prop("disabled", false);
                $("#type_select_hockeyschools").removeProp("disabled", "disabled");
                $("#sch_cat_hockeyschools").prop("checked", true);
                $("#sch_cat_hockeyschools").prop("checked", "checked");
            }, function(ev) {
                ev.stopPropagation();
                $("#type_select_hockeyschools option:selected").removeAttr("selected");
                $("#type_select_hockeyschools").prop("disabled", true);
                $("#type_select_hockeyschools").prop("disabled", "disabled");
                $("#sch_cat_hockeyschools").prop("checked", false);
                $("#sch_cat_hockeyschools").removeProp("checked");
            });

Sample of corresponding checkbox HTML:

<input class="catmark" type="checkbox" name="sch_categories[]" id="sch_cat_hockeyschools" value="1" />General Hockey Schools
<input class="catmark" type="checkbox" name="sch_categories[]" id="sch_cat_springhockey" value="2" />Spring Hockey

The problem is that the upon clicking the checkbox, the checkbox does not become ticked or checked; it immediately returns to an unchecked state, which I thought the stopPropagation() function would help with. Apparently not. The multi-lists get enabled and disabled as expected, but the checkbox doesn’t get ticked.

The result of this problem is that when the form is submitted, the array containing the selected categories is empty; thus, because at least one checked category is a required field in the form, the PHP script that processes the form throws one of my errors which tells me a required field was left blank.

Any ideas on how to make sure that the checkbox actually gets checked, and by extension, POSTS actual data to the processing script?

Thanks guys.

Answer 1

The problem is the use of toggle — per the documentation:

The implementation also calls .preventDefault() on the event, so links
will not be followed and buttons will not be clicked if .toggle() has
been called on the element.

toggle itself is calling preventDefault, which is stopping the default behavior of the event, checking/unchecking the box.

Rather than toggle, use bind or on (see edit note below) to add a listener for the change event, in which you can examine the state:

$('#sch_cat_hockeyschools').on('change', function () {
    if (this.checked) {
        // do stuff for a checked box   
        console.log('check is on');
    } else {
        // do stuff for an unchecked box        
        console.log('check is off');
    }
});

Try it out at jsFiddle.

EDIT
Please note, this code shows use of the on method, whereas the jsFiddle example uses bind. As pointed out by Sam Sehnert, on is the preferred method for attaching events with > jQuery 1.7. If you are using an older version of jQuery, use bind as in the jsFiddle example.

Documentation

• jQuery.toggle
• jQuery.bind
• jQuery.on