My rails website uses the open_flash_graph plugin to generate flash graphs for my clients. If a customer doesn't have flash installed, it doesn't display any messages, it simply doesn't show any graphs.
I've noticed that if I go to other websites that need flash, I get a yellow bar at the top of my firefox window that offers to "Install Missing Plugin".
I assume something in the HTML lets firefox know that this webpage needs flash. What code do I need to add to my website to make this work?
You could try using a simple flash button down at the bottom of the screen that is embedded in the HTML so when a user goes to the site Firefox will know it needs flash. I'm not entirely sure why it would not trigger the installer bar if a flash object is embedded in the generated code.
When you use the open_flash_chart_object function the forth parameter is use_swfobject. By default this is set to true, which causes the chart to degrade very gracefully if flash is not installed. If you set this parameter to false, then the "Install Missing Plugin" message will get triggered.