VSIX LanguageService FindToolWindow(...) returns null

Question

I have two VSIX packages (VS2010 SDK), one containing a LanguageService and one the ProjectPackage (based on Managed Package Framework for Projects) for my language. Now I need to establish some sort of communication channel where the LanguageService can retrieve additional information from the ProjectPackage. In the ProjectPackage, the information is available via a toolWindow, which can be retieved using

package.FindToolWindow(typeof(HierarchyViewerWindow), 0, false) as HierarchyViewerWindow;

The LanguageService inherits from the same Package base Class as the ProjectPackage, so I thought I could use the same mechanism here. The call returns null though.

So the basic question is whether I am doing something wrong or this is impossible for some reason... Or if there is a better way to establish communication between a LanguageService and another VSIX package.

Answer 1

Your ProjectPackage can Provide a Custom Service and your LanguageService can access it via the standard GetService call.