Changing value of table cell

Hello all,

I am trying to do the following:

I have a table on a page, which has 3 columns. When a user selects a row, and clicks on the button find, a popup window will appear, and the user can click through some fields. At the end, the user selects a value, and clicks on a button.

When that button is pressed, the selected value has to be inserted into the 2nd column of the row the user selected.

How can I do that? One big problem is, that I don't have the context available. The columns for the table are not defined in the context statically, I guess dynamically. (I am modifying an existing web dynpro)

Thanks in advance!