I am facing problem with Google pie chart and Update panel. Their is one Tab container inside a update panel which has two Tab panels. Each tab panel contains div and script to plot Google pie chart. when first time page gets load it works properly. but if i change the tab then pie chart doesn't work. i have used "Sys.Application.add_load(methodname) inside each tab panel. i have used script which is in Google play. Thanks in Advance.
The call to google.load only loads the Visualization API and fires a callback the first time it is called only. Subsequent calls to google.load for the same package do nothing. If your charts draw in a callback from the google loader in your second tab, the callback will not fire, so you need to use a callback from the update process instead.
来源：https://stackoverflow.com/questions/24390232/google-pie-chart-any-chart-not-working-inside-an-asp-net-ajax-update-panel