JQuery Change Event Loop

Question

Hello all,

I have several checkboxes. If a user checks any of them, I have to see if they are allowed to do that, if not, notify them and uncheck it. However, this get me in a loop as it triggers the change again! How can I over come this?

$('#step_1, #step_2, #step_3, #step_4').change(function(event) {
        if(!$('#section_2_active').attr('checked')){
            alert('You can not select output options when "Create Output" has not been selected.');

            $(this).attr('checked', false);

            $('#other_stages :checkbox:not(#section_2_active, #co_t)').change();
        }

});

I can not unbind and then rebind the change event as there is another plugin that is reliant on this event.

What other options do I have? I can attach a function call to each checkbox but I am hoping for something a bit more elegant, if not, I will default to this.

Thanks all for any help

Answer 1

The simplest change is something like this:

var inClickHandler = false;

function OnChecked(evt) { 
  if (inClickHandler) {
    inClickHandler = false;
    return;
  }
  inClickHandler = true;

  // Do your stuff.
}

Answer 2

You can use .trigger() to pass an additional parameter to your handler, we'll use loop. If it's false, don't run the other-element trigger again, like this:

$('#step_1, #step_2, #step_3, #step_4').change(function(event, loop) {
  if(!$('#section_2_active').attr('checked')){
    alert('You can not select output options when "Create Output" has not been selected.');
    $(this).attr('checked', false);
    if(loop !== false) 
      $('#other_stages :checkbox:not(#section_2_active, #co_t)').trigger('change', false);
  }
});

Answer 3

Why do you call this line? $('#other_stages :checkbox:not(#section_2_active, #co_t)').change(); As far as I can see you don't need this and it won't then loop. The checkbox will still check unless you use event.preventDefault(); and the .attr('checked',false); won't trigger change, probably because of the issues you're having.