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Flutter lifecycle used with .autoDispose modifier

I been trying to understand how Riverpod works and was wondering how does it know when to destroy the state of a provider with the .autoDispose modifier when changing a route in Flutter. Is it somehow subscribed to the navigator changes?

The docs state:

A common use case is to destroy the state of a provider when it is no-longer used.

There are multiple reasons for doing so, such as:

- When using Firebase, to close the connection and avoid unnecessary cost.
- ***To reset the state when the user leaves a screen and re-enters it.****
Solution

  • The "autoDispose" logic doesn't depend on Flutter-specific logic.
    Instead it relies purely on whether a provider is currently being listened or not.

    When a route is poped, the associated widgets are destroyed. This causes the ConsumerWidgets in that route to stop listening to their "watched" providers.

    Then, if a provider now has no more listener, it gets disposed.