Is there a way to detect whether or not there is an opened solution in VS 2012 from a vsix extension?

Question

I would like to disable parts of my extension's tool window if it is opened without a solution loaded, and need a way to detect this.

I know about the DTE events that are fired when a solution is opened/closed, is there perhaps a similar event for when the IDE itself has finished loading?

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Answer 1

I found my answer while writing the question, but I thought I may as well still submit in case anyone else is looking for this in future with similar search terms to me.

EnvDTE.Solution.IsOpen

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