Field not visible untill refresh

I have added a read only field. In kanban view when i move a kanban card to a particular status then only that field will be visible. Now it is coming but i need to refresh. I need to pop-up this field when i move card without refresh.

here is my js code:

onload: function (frm) {

       if (frm.doc.status=='Kickoff Requested' && frm.doc.kick_off_start==null){
                method: 'testapp.testapp.doctype.testdoc.testdoc.update_kick_off',
                callback: function(r){
                        frm.set_value('kick_off_start', r.message);
                        frm.set_df_property('kick_off_start', 'read_only', 1);

Any suggestions ???

you can use refresh_field(“your_fieldname”) in callback .