How do you structure Android navigation?

Direct answer

What a strong answer covers

How it works

Navigation is modelled as a graph of destinations with typed arguments, whether through Navigation Compose, the XML navigation component, or a hand-rolled back stack. Screens receive arguments and emit events; the decision to navigate lives in one place, such as a ViewModel event handled by the host, so reusable composables do not depend on the navigation library. Deep links map URLs to destinations with a synthesised back stack, the back stack is saved for process death, and nested graphs group flows such as onboarding or checkout that have their own entry and exit rules.

Example

A checkout flow is a nested graph with cart, address, and payment destinations sharing one ViewModel scoped to the graph; finishing payment pops the whole graph back to the order list. Opening a push notification for an order deep-links to the order detail with the order list beneath it, so the back button behaves the same as if the user had navigated there.

Common mistakes

• Passing whole objects as arguments instead of IDs and hitting size limits or stale data.
• Calling the NavController from inside reusable composables and coupling them to the graph.
• Ignoring process death so a restored app lands on a screen with null arguments.

A useful answer structure

Answer from your own work.

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