problem with event on join table

Nicola.A

Hi,

i have this code on my JS file. I have change the table with a join, in the origin was with only one table, and now that don't work.
You can help me?
Thanks

        editor.field('table1.start_date').input().on( 'focusout', function () {
        editor.field('table1.end_date').val("");
        var date = editor.field('table1.start_date').get();
        if (date.length == 8) {
        var res = date.split("-");          
        res[2] = parseInt(res[2]) + 3;
        editor.field('table1.end_date').val( res[0] + "-" + res[1] + "-" + res[2] );
        }
    } );