Passing data between two viws of two windows

Hi,

I have a requirement where I have two views embedded to two different windows, so V_MAIN to W_MAIN and V_SECOND to W_SECOND. I have a button on my first view OPEN, when a user clicks on OPEN it calls the second window and the corresponding view V_SECOND as a pop up. User will select a document number listed on the second view, now what I want to do two things here:

1. The document number that user selected in the pop up should go to the V_MAIN.

2. Now based on the document number the V_MAIN should be pre populated.

In the past I have used plugs to move between the views of the same window but I haven't done the scenario like this.

Any suggestion please.