lightbox readonly

readonly - (boolean) if you set the “true” value, the section will be read-only
(for the time, duration controls only)

How to make a parent field readonly in edit mode …?

you can disable input manually, using onLightbox event:gantt.attachEvent("onLightbox", function (task_id){ var parent = gantt.getLightboxSection("parent"); var select = parent.node.getElementsByTagName("select")[0]; select.setAttribute("disabled", true); });
note, that select element does not have a ‘readonly’ attribute, and you’ll have to use a ‘disabled’. … event.html … ction.html

Or you can create a template control and use it for showing parent name: