Architecture question/discussion: piping down higher level routers?

Say I have a router for some full screen parent controller, then in some nested child controller I want to start a transaction that pushes a new full screen controller. Any advice on this? Pass down the raw router from DI? Wrap it?

Start by reviewing the existing router and controller APIs, focusing on how nested child controllers access a parent router and how dependency injection is used. Determine whether passing the raw router or wrapping it is supported for starting a full-screen transaction, then document or implement a settled approach for this architecture question.

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