Given the clarification in the the comments. I can say that if it is possible it would require significant amounts of Java or JavaScript to accomplish.
By the time the report is displayed to the user in the web window, all of the report creation is completed. There are not any easily defined click and/or drag rules in BIRT to have different display changes based on activity after the report is created.
It is likely possible to do as you wish. If you can write enough Java or JavaScrip you can do pretty much anything in BIRT. But I think the skills required would be beyond what you or I currently have.