APEX

Hi,

Here is what i want to do :

On my page FORM_A i have a form to insert into Table A
in this table i have a foreign key to Table B

From within FORM_A, when i click on the button "ADD B" , i want a popup to open and display the page FORM_B, which holds a form for Table B.
Once i create the new entry in table B, i want this popup to close and come back to the orignal form A i was filling in. But now, the foreign key field should have the value (Primary key from table B) of the entry i just created in the Table B.

I have tried playing around with the exemples from Denes Kubicek apex webpage, but i couldnt achieve exactly what i wanted.

Thanks for the help