I have seen a number of people with this problem on here - but never a solution. I have an application which has a number of themebasedfois over the top of a google map. There could be multiple themes at any one time. What I can do in Internet explorer 7 and 8 is hover over any theme and click any foi. i.e. I can see the info window for any foi and any foi that has an event attached to it (e.g. MVEvent.MOUSE_CLICK) is fired when I click on that theme. In IE9/10, chrome, firefox and maybe others I can only hover over or click on the top most foi layer, i.e. the one that was added last. The fois don't have to be near each other, but only the top one is clickable/hoverable. Now, I have seen people suggest setBringToTopOnMouseOver - but that doesn't work at all, it is like the top foi has a border that hides the other fois from the mouse?
I have worked around this by allowing turn on/off of fois, however this is not practical for the users - and their only workaround is to keep IE8 - which is not going to last for long. I have tried this in multiple mapviewer versions - including the current one. The same issue is present whether I use Weblogic, Glassfish or oc4j/soa. I must have tried a million different things. Can someone please offer some insight or a fix for this or tell me what I am doing wrong?
Unfortunately what you are seeing today with FF/Chrome/IE 9+ is actually the expected behavior. When you have multiple FOIs from different themes, even if they appear apart from each other, each is rendered into a rectangular PNG image with a transparent background and those image boundaries are probably overlapping. In IE 7 and 8, due to the browser's proprietary way of handling PNG transparency (with the use of an alpha filter plugin) user can actually click through the transparent portion of the top FOI image and the event will reach down to the bottom FOI. But again this 'feature' is available purely due to IE7/8's use of the png transparency filter. Generally speaking this is not supported in other browsers, there are some tricks to implement this (such as the pointer-events mentioned in this thread http://stackoverflow.com/questions/3080746/clicking-through-a-transparent-png), but no widely available solution exist yet.
Maybe try letting user control the display z-order of the themes so that the active (clickable) theme is always on top?