I have an application where I use a Google map and a GTileLayer to draw PNG overlays provided by a WMS server. It works perfectly all the time, except when I use Internet Explorer 8 and let the application run in the browser without any activity for more than about 10 minutes. When I return from the idle period and do some action on the map (for instance zoom in), some of the tile overlays fail to load. I look at the traffic of requests in the browser, and usually it is about 20 tile requests to gmaps and 20 tile requests to my WMS server. But in the case of zooming after idle time it is only requested about 8 tiles. Which tiles are loaded and which tiles are not seems to be random. The issue disappears if I zoom again. It does only seems to affect the first thing I do when returning from an idle period.
To me this seems to be some kind of timeout (or possibly cache?) issue, but I can't quite figure out why a timeout would make _some_ of the tiles load. Also I was surprised to see that the requests for the missing tiles were not run at all. At first I figured that it must be the server that is not delivering what it is supposed to do, but now it seems this is a client-side issue since the missing tiles are never requested. In my javascript code I have overridden the getTileUrl() method of the GTileLayer object in order to generate the correct request URL for each tile. I have debugged out the URLs, and it seems that all of them are generated properly (meaning that Google runs the method for all the 20 tiles). So does it make any sense that only some of these URLs are actually run? I have tried to test this in both IE8, Firefox 4 and Chrome 4, and so far I have only been able to reproduce the issue in IE8. All hints and help will be appreciated! -- You received this message because you are subscribed to the Google Groups "Google Maps API" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-maps-api?hl=en.
