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kotlinlang

How do you navigate from an Android `Service` to a Navigation Component destination (fragment)?

I think you’ll need to create an intent that contains the desired destination id as an extra, then use it to launch or resume an `Activity` that has a Navigation Host with the desired destination in its nav graph.

You mean like this?:
```val pendingIntent = NavDeepLinkBuilder(context)
                     .setComponentName(YourActivity::class.java)
                     .setGraph(R.navigation.your_nav_graph)
                     .setDestination(R.id.your_destination)
                     .setArguments(bundle)
                     .createPendingIntent()
context.startActivity(pendingIntent)```

<@UBGP9J146> this doesn't work, as `startActivity()` requires an Intent, not a pending intent

I was thinking you’d do it more manually like <https://stackoverflow.com/questions/3606596/android-start-activity-from-service|this> and then write custom logic in the `Activity` `onCreate` or `onNewIntent` methods to interact with the `NavHost.`

I was hoping the NavDeepLinkBuilder fixed that, but I guess since it only creates pending intents it can’t be used.

I see, but I worry that it will result in two main activities running

I could use Activity launchMode singleInstance, but apparently it prevents OnActivityResult callbacks

```        val activityService = getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
        val appTasks = activityService.appTasks
        if(appTasks.size&lt;1){
            launchNewApplicationInstance()
        }else{
            appTasks.get(0).moveToFront()
        }```

I’ve done this before, it seemed to work

might be tricky to pass the destination along though

You shouldn't be using `createPendingIntent()` - use `createTaskStackBuilder().startActivities()`

Note that `NavDeepLinkBuilder` already sets the appropriate flags so you won't have a separate instance (it replaces the current instance - don't use any `launchMode` flags)

:heavy_plus_sign: :one:  that’s awesome, Ian

But keep in mind that on newer versions of Android, you can't start activities from the background at all, so your initial idea probably needs to be rethought entirety. Generally, you'd post a notification and it would be up to the user to choose to open your app

<@UJBPFB3SN> so you’d probably use the pending intent with the notification to give the user control over what happens, right? I’m still new to the navigation api.

Yep, that's what the `createPendingIntent()` API is for

You can read more about starting activities from the background and the alternatives on the documentation: <https://developer.android.com/guide/components/activities/background-starts|https://developer.android.com/guide/components/activities/background-starts>