Android 在Service中使用ViewModel

别想了，官方并不推荐这种做法。
ViewModel应该与Activity或Fragment紧密结合使用，因此它注定要存在于应用程序的UI层中。因此，我不建议在Service中使用ViewModel。可以将Service和ViewModel的公共代码抽出。
具体参考：
https://github.com/android/architecture-components-samples/issues/137#issuecomment-327854042

The ViewModel should be used closely with an Activity or a Fragment, so it’s destined to live in the UI layer of your application. Therefore, I don’t recommend using the ViewModel in a Service. Create a different class, that would be used in the Service and, if needed, in the ViewModel. Like this you ensure the separation of concerns and avoid giving the ViewModel more responsibilities than needed.