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I am working with the designer host code provided by Vihang on msdn. I am creating a state workflow. I have defined an interface that has the attribute of "ExternalDataExchange" and a class that implements it. I then add this assembly to the designer host application via the WorkflowLoader's initialize method using this code:
 typeProvider.AddAssemblyReference(typeof (MyAssembly.Services.DocumentService).Assembly.Location);
 
After adding the "handleExternalEventActivity" to the EventDrivenActivity in the StateActivity I select the the interface IDocumentService in InterfaceType property dialog and receive the following error:
System.Workflow.ComponentModel.Design.IExtendedUIService must be installed for this operation to succeed. Ensure that this service is available"
 
Looking at the way services are added in the code:host.AddService(typeof(IMemberCreationService),new MemberCreationService(host,this));
I don't see a type that implements IExtendedUIService, so I cannot load it.
I know this interface has changed from beta2 to beta2.2. The document for the key changes states this interface must be implemented by the host of the designer. I do not receive this error when loading the type in the VS2005 designer.
Any help would be greatly appreciated.
 
smc750
 

What happens if you implement and add IExtendedUIService? Do you still receive the error?

What happens if you implement and add IExtendedUIService? Do you still receive the error?

That took care of the problem. However, can you point me to some documentation on why and how I need to implement this service. For example, what are these methods used for?
Any help would be greatly appreciated. The code is a great example to learn from.
 
smc750

One of the use of the service is to navigate from the smart tag error to the property in the property browser. It is also used in case of InvokeWebService to add webreference.