I am trying to send a network request inside the `viewModelS

Question

I am trying to send a network request inside the `viewModelScope` while closing the screen Network request gets canceled as coroutine scope is canceled How do I send a network request upon closing the screen

streetsofboston · Answer

The class that runs your network requests should have their own lifecycle Look at the Switching CoroutineScopes section here <https link medium com gx3HrpwQqkb|https link medium com gx3HrpwQqkb> a bit of shameless self promotion grin

K Merle · Answer

If I d bound it to custom `CoroutineScope` and run network request does scope cancels itself after all suspend functions are called

Francesc · Answer

You can use `withContext NonCancellable `

K Merle · Answer

What I aim for is do the network request and after that for CoroutineScope to cancel itself Is this possible

K Merle · Answer

I suppose this would do the job ```private var job Job = null job = CoroutineScope IO launch networkRequest job cancel ```

streetsofboston · Answer

Why would you want the CoroutineScope to cancel itself when the Job is done In your example the call to job cancel doesn t do much It is called as the last thing in the job and the job would ve ended anyway why cancel it

streetsofboston · Answer

Note that Job = CoroutineScope When a job ends the CoroutineScope may live on and be able to launch other jobs at a later time

K Merle · Answer

Ahh

streetsofboston · Answer

Also depending on your use case the suggestion from < Francesc> is a great one as well

K Merle · Answer

Would having a singleton CoroutineScope make sense then and reuse it for these kind of works

streetsofboston · Answer

Yup absolutely And if you don t want to have your CoroutineScope cancelled on one request failing and therefore no longer able to launch future requests be sure to give it a SupervisorJob

K Merle · Answer

As for a < Francesc> answer does this mean I could run `withContext NonCancellable ` inside viewModelScope

streetsofboston · Answer

Or better make the object making these requests a Singleton and let it have its own CoroutineScope

K Merle · Answer

Thanks guys

streetsofboston · Answer

Be sure to wrap withContext NonCancellable around just your network call not around the call to your UI

K Merle · Answer

<https medium com androiddevelopers coroutines patterns for work that shouldnt be cancelled e26c40f142ad> ```Whenever you need some work to run beyond its current scope we recommend creating a custom scope in your Application class and running coroutines within it Avoid using GlobalScope ProcessLifecycleOwner scope and NonCancellable for this type of work ``` I might go for a singleton CoroutineScope in the end