Will Prism OnDemand module loading work in an OOB scenerio?

Question

Should the loading of OnDemand Prism modules work in an OOB scenerio? If so, I cannot seem to make it work. Everything is currently working in browser without any problems. Specifically I: register my modules in code:

    protected override IModuleCatalog GetModuleCatalog() {
        var catalog = new ModuleCatalog();
        Uri source;

        if( Application.Current.IsRunningOutOfBrowser ) {
            source = IsolatedStorageSettings.ApplicationSettings[SOURCEURI] as Uri;
        }
        else {
            var src = Application.Current.Host.Source.ToString();
            src = src.Substring( 0, src.LastIndexOf( '/' ) + 1 );
            source = new Uri( src );
            IsolatedStorageSettings.ApplicationSettings[SOURCEURI] = source;
            IsolatedStorageSettings.ApplicationSettings.Save();
        }

        if( source != null ) {
            var mod2 = new ModuleInfo { InitializationMode = InitializationMode.OnDemand,
                          ModuleName = ModuleNames.mod2,
                          ModuleType = "mod2.Module, mod2.Directory, '1.0.0.0', Culture=neutral, PublicKeyToken=null" ),
                          Ref = ( new Uri( source, "mod2.xap" )).AbsoluteUri };

            catalog.AddModule( mod2 );
        }

// per Jeremy Likeness - did not help.
        Application.Current.RootVisual = new Grid();

        return ( catalog );
    }

later request for the module to be loaded is made:

mModuleManager.LoadModule( ModuleNames.mod2 );

and wait for a response to an event published during the initialization of that loaded module.

The module appears to never be loaded, and when the application is running under the debugger there will be a message box that states that the web server returned a 'not found' error. I can take the requesting url for the module and enter it into Firefox and download the module with no problem.

I have not been able to find any reference to this actually being workable, but it seems as though it should. The most I have found on the subject is a blog entry by Jeremy Likeness, which covers loading modules in MEF, but applying his knowledge here did not help.

The server is localhost (I have heard it mentioned that this might cause problems). The server has a clientaccesspolicy.xml file - although I don't expect that is needed. I am using the client stack and register it during app construction:

WebRequest.RegisterPrefix( Current.Host.Source.GetComponents( UriComponents.SchemeAndServer, UriFormat.UriEscaped ), WebRequestCreator.ClientHttp );

Followup questions:

Can all of the xaps be installed to the client desktop in some manner - or only the main application xap? specify them in appmanifest.xml somehow??

Is it worth it make this work if only the application.xap is installed and the rest of the xaps must be downloaded anyway?

Answer 1

Hi, Once I worked on a similar scenario. The trick is having the modules stored in isolated storage and use a module loader that reads from isolated storage when working offline.

This is because otherwise, you can't get download the modules that are in a different .xap file than the Shell.

Thanks, Damian