In that case, I would do it differently.
In the class initialize, create something like
Sub Initialize(pModule as Object, pEventname as String)
and then assign them to local class variables (mModule, mEventname).
Later when you need to call the main activity, do:
CallSub(mModule, mEventname)
Then in the Main activity,
have the event as a sub:
Sub clsManager_Update
btn3_Click
End Sub
This way, all the view or dependent logic is still inside the activity, and the class can be reusable.
You can have a look at some examples of classes on the forums.