Question

I’m working on a Silverlight 4 application that seems to run fine in IE, however when I try to view the application in FireFox, the application loads, but is not visible. The application is definitely loading, despite not being visible. I’ve run Fiddler and can see that the application makes the two web service calls I expect it to when the app loads.

The HTML hosting the Silverlight plugin is very simple, containing only a div with an object tag inside. There are no styles that would impact visibility of the containing div.

The HTML is below:

<div id="silverlightControlHost">
    <object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
        <param name="source" value="ClientBin/Shell.xap"/>
        <param name="onError" value="onSilverlightError" />
        <param name="background" value="white" />
        <param name="minRuntimeVersion" value="4.0.50826.0" />
        <param name="autoUpgrade" value="true" />
        <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50826.0" style="text-decoration:none">
            <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/>
        </a>
    </object>
    <iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe>
</div>

One last point that I just noticed, the problem with the Silverlight app not being visible only occurs when viewing the HTML page in FireFox via my local IIS. If I open the HTML page directly from the file system, the Silverlight app is visible.

Any suggestions as to how to fix this visibility problem would be greatly appreciated.

Answer 1

I was able to solve the problem by setting the size of the object tag to a fixed pixel size. Previously we had it set to 100% width and height. Once I changed to fixed pixel for width and height, I was able to view our application in both IE and FireFox.