Set a ViewModel's property, By opening another View(binded to another ViewModel) from the Main View?

Inter-ViewModel communication is easily handled by MVVMLight's Messenger or Caliburn. Micro's EventAggregator. I preferred Caliburn.

Micro's implementation since it was interface based rather than subscribing directly to message types. This allows for far more flexibility with inheritance of base classes.

It seems the same as How to Open a New Window from VM. There are some solutions.

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