IAM USING APEX 4.1 , Oracle 11g enterprise edition , PL/SQL Gate way
The user will enter the details in the apex form that capture basic details of the customer and my requirement is when user enter the button
The same details that he entered should be shown as a popup window..
(The purpose of having this window is just to show him the details he entered)
after that he click on CREATE and save entry.
You could try using the skillbuilders modal plugin. Google it if you are not familiar with skillbuilders.
In effect, the second (modal) page is the one that submits the data. Just put cancel and confirm buttons on the modal page.
If the cancel button is clicked you just close the modal and revert to the original page. If the confirm is clicked you submit the data and close the modal + redirect if required.