DevForce Community Forum : Dynamic load workspaces

Dynamic load workspaces : Here's an example I wrote...

Sat, 13 Oct 2012 11:44:57 -700

Author: mgood
Subject: 3712
Posted: 13-Oct-2012 at 11:44am

Here's an example I wrote a while back for a customer in Germany, so it's got some German comments in there. It's SL4, but I just updated it to the latest version of Cocktail.

uploads/1005/ApplicationStarter.zip

Dynamic load workspaces : Thank you Marcel, Sounds logical. I've...

Sat, 13 Oct 2012 05:37:33 -700

Author: Peter
Subject: 3712
Posted: 13-Oct-2012 at 5:37am

Thank you Marcel,

Sounds logical.

I've added the following within the module.

[Export("MainViewModel", typeof(IWorkspace))]
public class MainViewModel : Screen, IWorkspace, IDiscoverableViewModel
{

But, OrganisationModuleFactory property is still throws a null exception.

Is there a complete example so I can compare my module.

I believe I'm forgetting something within my module implementation.

Again, thank for your help.

Peter

Dynamic load workspaces : Peter,Your code above is looking...

Fri, 12 Oct 2012 11:55:57 -700

Author: mgood
Subject: 3712
Posted: 12-Oct-2012 at 11:55am

Peter,

Your code above is looking for an export named "MainViewModel" and type IWorkspace. That doesn't match the ExportAttribute you have on your ViewModel. It should be like this:

[Export("MainViewModel", typeof(IWorkspace)]

Dynamic load workspaces : Hello Cocktail colleague's, Iâ€™m...

Fri, 12 Oct 2012 06:14:07 -700

Author: Peter
Subject: 3712
Posted: 12-Oct-2012 at 6:14am

Hello Cocktail colleague's,

I’m writing my first cocktail Silverlight (SL5) application en getting familiair with MEF.
So, I’m new to this.

I’m trying to dynamically load a IWorkspace ViewModel from a separate XAP file. I’m using the example found in the documentation.
On the main SL application (the one loading a SSHBizzOrganisation module) I have the following code.
Basically copied from the example.

[Import("MainViewModel", AllowRecomposition = true, AllowDefault = true)] 
public ExportFactory OrganisationModuleFactory { get; set; }
 
private IEnumerable ShowOrderDetail(OrganisationModuleMessage message) {
// Let's make sure the xap that contains the OrderEditor is loaded. 
// Only the first call will load the xap, subsequent calls don't do anything. 
yield return Composition.AddXapAsync("SSHBizzOrganisation.SL.xap");
// Now we can access the OrderEditorFactory. MEF recomposed this instance 
// and provided us with an OrderEditorFactory. 
var editor = OrganisationModuleFactory.CreateExport().Value;
var handler = editor as IHandle; 
if(handler != null) handler.Handle(message); 
}

When I run this, the AddXapAsync(..) call is working fine.
But the ‘OrganisationModuleFactory’ property is always null.
I’m sure I forgetting something here of within the module implementation.

The SSHBizzOrganisation module looks like this:

namespace SSHBizzOrganisation.ViewModels
{
[Export(typeof(IWorkspace))]
public class MainViewModel : Screen, IWorkspace, IDiscoverableViewModel
{
public MainViewModel()
{ // ReSharper disable DoNotCallOverridableMethodsInConstructor
DisplayName = "Desktop";
// ReSharper restore DoNotCallOverridableMethodsInConstructor
}

I have read some of the forum posts, but I probably missing some basic understanding.
It’s not clear to me if I should use the PartFactory implementation or just use the [Export] attribute like I’ve done above.

I have tried both.

Hope some can point me in the right direction.

Peter