How to get the index of a check box within a repeatable subform

Hi,

I'm making a livecycle form which consists several subforms named "person1", "person2".. like that. Within each person# subform, there is an another subform "task". It is repeatable by clicking a button to 'add instance'. There is a checkbox within "task" subform.

My problem: I need to add an "if" condition depends on the status of that check box.

                if (xfa.resolveNode("task["+ i +"].CheckBox1").rawValue == false)

                      {         

                        *********

                        }

I think that " i " value in above code should be the index of relevant "task" instance. But I do not know how to get it. this.parent.index doesn't give the value.

can anyone please help me?

any idea will be valuable for me!