Hi everyone I was going through the Jetpack Now In Android o

Question

Hi everyone I was going through the Jetpack Now In Android official sample Really great sample but I couldn t find any example of navigation triggered by ViewModel there In my apps I use Channels to send navigation events from ViewModel but Google seems to be recommending against this approach I have gone through a lot of official samples but haven t found one which demonstrates how to handle navigation triggered by ViewModel Does anyone know of any such sample official or unofficial Maybe < Manuel Vivo>

Csaba Szugyiczki · Answer

I think there is nothing wrong with your approach We are doing kind of the same in our apps but instead of Channels we started to use SharedFlows So we are connecting our ViewModels with the NavController in the MainActivity through a Singleton object that can be injected both in the Activity and all of our ViewModels

Arpit Shukla · Answer

Yeah like the Channels approach never failed me at least I never noticed Just wanted to see an example of the approach that is being recommended everywhere because I find it quite hard to model my events as state

ppvi · Answer

Here you have an example When `isTaskSaved` is set to true <https github com android architecture samples blob d31721fbc00d95e5007dd88bf4696350262be435 app src main java com example android architecture blueprints todoapp addedittask AddEditTaskViewModel kt L44|https github com android architecture samples blob d31721fbc00d95e5007dd88bf4696 itecture blueprints todoapp addedittask AddEditTaskViewModel kt>

ppvi · Answer

then a callback in the compose screen is called arriving here where the navigation happens <https github com android architecture samples blob d31721fbc00d95e5007dd88bf4696350262be435 app src main java com example android architecture blueprints todoapp TodoNavGraph kt L96|https github com android architecture samples blob d31721fbc00d95e5007dd88bf4696 example android architecture blueprints todoapp TodoNavGraph kt>

ppvi · Answer

the key part is that you don t send an event from the viewmodel called navigateToHome Instead you set the state to be task is saved and let the compose screen in this case the nav graph make the decision

Arpit Shukla · Answer

Thanks for the example so in this case we remove the current destination from the backstack while navigating For the case where we move a step forward we will also have to reset this boolean to false again right Otherwise when user comes back to this destination he will again be navigated

Arpit Shukla · Answer

< ppvi> Could you please confirm this

ppvi · Answer

you have to either reset the boolean or make sure that your viewmodel is recreated when you navigate back to the screen