I'm using navigation component, and I wanna detect when user navigates back from fragment B -> A, so I can save a note in room database table created in fragment B before navigating back to fragment A (I'm making a note app, and I wanna save notes just like Google keep note app does).
This should here
There are a couple of alternatives to the shared view model.
fun navigateBackWithResult(result: Bundle) as explained here https://medium.com/google-developer-experts/using-navigation-architecture-component-in-a-large-banking-app-ac84936a42c2
Create a callback.
ResultCallback.kt
interface ResultCallback : Serializable {
fun setResult(result: Result)
}
Pass this callback as an argument (note it has to implement Serializable and the interface needs to be declared in its own file.)
<argument android:name="callback"
app:argType="com.yourpackage.to.ResultCallback"/>
Make framgent A implement ResultCallback, fragment B by will get the arguments and pass the data back through them, args.callback.setResult(x)
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