How to set default value for reference field , only when that field value is empty

[kalyani23]

Hi ,

I want to set default value in parent field (type reference), only when the field value is empty.

i have given this below code line :

javascript:current.parent= current.parent_activity.parent.toString();

but looks like not working . 

Can anyone help with this code.

Thanks in advance

Kalyani

[kalyani23]

Hi Timi,

tried the above code and is not working