Look into the dojo docs. It's probably re-creating the tab's contents every time you click on it, which would re-load anything within it, like a Flex chart. The chart will not re-load itself.
Dump the dojo and use a flex Tab navigator, instead. tah-DAH!
I removed the dojo but i need to display flex charts in the JSP page. I display charts inside the HTML div element. But if div element is hidden using style="display:none" and then shown using style="display:block" , the flex chart restarts. So just by hiding and displaying div element chart is restarting.
Any idea why ?