A cascading. multi-select list box on a Submission - that has "select check boxes"

[Roderick]

I need to create a cascading. multi-select list box on a Submission - that has "select check boxes" associated with each option, and a "select all" button.

I have explored two solutions, both of which don't work.

 

Solution 1: I know that I could set the data type to List - String, and then multi-select becomes a standard option (with a "select all" option as well). But the problem with that standard solution is that it does not allow for cascading based on another fields in the Submission Form.

Solution 2: I also know that I could use a Cascading List Box, together with the following JS code:

<SCRIPT LANGUAGE="JavaScript">

 /* "fieldName" is the variable name for the listbox type form element field. */

   var fieldName = "InsertRecordCompany";

   var x=document.getElementsByName(fieldName);

   x[0].multiple=true;

</SCRIPT>

But the problem with that solution is that the list box does not have "checkboxes" on the side, nor a "select all" button. This makes that solution clumsy for users.

Can you help me implement what I need - a cascading. multi-select list box on a Submission - that has "select check boxes" associated with each option, and a "select all" button

[Roderick]

I used select2 with multiselect in order to make it a bit more user friendly.