Improve behavior when restarting app via app lauchner

mailbox-android/src/main/java/org/briarproject/mailbox/android/StatusManager.kt

@@ -26,7 +26,6 @@ import androidx.annotation.StringRes
 import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.GlobalScope
-import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.SharingStarted.Companion.Lazily
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.combine
@@ -74,7 +73,7 @@ class StatusManager @Inject constructor(
     object Stopped : MailboxAppState()
 
     @Suppress("OPT_IN_USAGE")
-    val appState: Flow<MailboxAppState> = combine(
+    val appState: StateFlow<MailboxAppState> = combine(
         lifecycleState, torPluginState, setupComplete
     ) { ls, ts, sc ->
         when {

mailbox-android/src/main/java/org/briarproject/mailbox/android/ui/MailboxViewModel.kt

@@ -33,6 +33,7 @@ import org.briarproject.android.dontkillmelib.DozeHelper
 import org.briarproject.mailbox.android.MailboxPreferences
 import org.briarproject.mailbox.android.MailboxService
 import org.briarproject.mailbox.android.StatusManager
+import org.briarproject.mailbox.android.StatusManager.MailboxAppState
 import org.briarproject.mailbox.core.lifecycle.LifecycleManager
 import org.briarproject.mailbox.core.lifecycle.LifecycleManager.LifecycleState
 import org.briarproject.mailbox.core.settings.MetadataManager
@@ -75,7 +76,7 @@ class MailboxViewModel @Inject constructor(
         setupManager.hasDb
     }
 
-    val appState = statusManager.appState
+    val appState: StateFlow<MailboxAppState> = statusManager.appState
 
     val lastAccess: LiveData<Long> = metadataManager.ownerConnectionTime.asLiveData()
 

mailbox-android/src/main/java/org/briarproject/mailbox/android/ui/MainActivity.kt

@@ -57,6 +57,7 @@ import org.briarproject.mailbox.android.StatusManager.Wiping
 import org.briarproject.mailbox.core.lifecycle.LifecycleManager.LifecycleState.NOT_STARTED
 import org.briarproject.mailbox.core.util.LogUtils.info
 import org.slf4j.LoggerFactory.getLogger
+import java.util.concurrent.atomic.AtomicBoolean
 
 @AndroidEntryPoint
 class MainActivity : AppCompatActivity(), ActivityResultCallback<ActivityResult> {
@@ -64,7 +65,8 @@ class MainActivity : AppCompatActivity(), ActivityResultCallback<ActivityResult>
     companion object {
         private val LOG = getLogger(MainActivity::class.java)
 
-        const val BUNDLE_LIFECYCLE_BEYOND_NOT_STARTED = "LIFECYCLE_BEYOND_NOT_STARTED"
+        const val BUNDLE_LIFECYCLE_HAS_STARTED = "LIFECYCLE_HAS_STARTED"
+        const val BUNDLE_ONBOARDING_DONE = "ONBOARDING_DONE"
     }
 
     private val viewModel: MailboxViewModel by viewModels()
@@ -76,6 +78,10 @@ class MainActivity : AppCompatActivity(), ActivityResultCallback<ActivityResult>
 
     private val startForResult = registerForActivityResult(StartActivityForResult(), this)
 
+    private var hadBeenStartedOnSave = false
+    private var onboardingLaunched = AtomicBoolean(false)
+    private var onboardingDone = false
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         LOG.info("onCreate()")
@@ -87,17 +93,28 @@ class MainActivity : AppCompatActivity(), ActivityResultCallback<ActivityResult>
             )
         }
 
+        LOG.info { "do we have a saved instance state? " + (savedInstanceState != null) }
+
+        hadBeenStartedOnSave =
+            savedInstanceState?.getBoolean(BUNDLE_LIFECYCLE_HAS_STARTED) ?: false
+        onboardingDone = savedInstanceState?.getBoolean(BUNDLE_ONBOARDING_DONE) ?: false
+
         launchAndRepeatWhileStarted {
             viewModel.appState.collect { onAppStateChanged(it) }
         }
 
-        LOG.info { "do we have a saved instance state? " + (savedInstanceState != null) }
+        checkForDbAsync()
+    }
 
-        lifecycleScope.launch {
-            val hasDb = viewModel.hasDb()
-            LOG.info { "do we have a db? $hasDb" }
-            onDbChecked(hasDb, savedInstanceState)
-        }
+    override fun onNewIntent(intent: Intent?) {
+        super.onNewIntent(intent)
+        LOG.info("onNewIntent()")
+        // We end up here when relaunching from the app icon. If the activity already existed, but
+        // the onboarding activity was on top, then the onboarding activity was finished because
+        // MainActivity has launchMode=singleTask and onCreate() will not necessarily be called
+        // before we reach this point.
+        onboardingLaunched.set(false)
+        if (viewModel.appState.value == NotStarted) checkForDbAsync()
     }
 
     private fun onAppStateChanged(state: MailboxAppState) {
@@ -125,51 +142,69 @@ class MainActivity : AppCompatActivity(), ActivityResultCallback<ActivityResult>
         }
     }
 
-    private fun onDbChecked(hasDb: Boolean, savedInstanceState: Bundle?) {
+    private fun checkForDbAsync() {
+        lifecycleScope.launch {
+            val hasDb = viewModel.hasDb()
+            LOG.info(
+                "hasDb? $hasDb, hadBeenStartedOnSave? $hadBeenStartedOnSave, " +
+                    "onboarding launched? $onboardingLaunched, onboarding done? $onboardingDone"
+            )
+            onDbChecked(hasDb)
+        }
+    }
+
+    private fun onDbChecked(hasDb: Boolean) {
         if (lifecycle.currentState == DESTROYED) {
             return
         }
-        if (savedInstanceState == null) {
-            if (!hasDb) {
+        /** This is for the situation when we come back to the activity after a remote wipe has
+         * happened while the app was in the background and gets restored from the recent app list
+         * after wiping and stopping has already completed.
+         * In this case onSaveInstanceState() has written true to the bundle and this value
+         * got restored to [hadBeenStartedOnSave]. */
+        if (hadBeenStartedOnSave && !hasDb) {
+            finish()
+            startActivity(Intent(this, WipeCompleteActivity::class.java))
+            return
+        }
+
+        if (!hasDb && !onboardingDone) {
+            // Make sure not to launch onboarding twice. In case of MainActivity being killed (due
+            // to do-not-keep activities option enabled), onDbChecked() gets called twice when
+            // relaunched via app launcher (through onNewIntent()).
+            if (!onboardingLaunched.getAndSet(true)) {
                 startForResult.launch(Intent(this, OnboardingActivity::class.java))
-            } else if (needsDozeWhitelisting(this)) {
-                nav.navigate(actionGlobalDoNotKillMeFragment())
-            } else {
-                nav.navigate(actionGlobalStartupFragment())
             }
+            return
+        }
+
+        if (viewModel.needToShowDoNotKillMeFragment) {
+            nav.navigate(actionGlobalDoNotKillMeFragment())
         } else {
-            // At this point, when we do not have a db, this can be either of two situations:
-            // 1. We just came back from the onboarding activity and our MainActivity has been
-            // destroyed in the meantime (can be forced using the do-not-keep-activities developer
-            // option). In this case onSaveInstanceState() has written false to the bundle.
-            // 2. We come back to the activity after a remote wipe has happened while the app was
-            // in the background and gets restored from the recent app list after wiping and
-            // stopping has already completed. In this case onSaveInstanceState() has written
-            // true to the bundle.
-            val savedBeyondNotStarted =
-                savedInstanceState.getBoolean(BUNDLE_LIFECYCLE_BEYOND_NOT_STARTED)
-            if (!hasDb && savedBeyondNotStarted) {
-                finish()
-                startActivity(Intent(this, WipeCompleteActivity::class.java))
-            }
+            nav.navigate(actionGlobalStartupFragment())
         }
     }
 
     override fun onSaveInstanceState(outState: Bundle) {
         super.onSaveInstanceState(outState)
         outState.putBoolean(
-            BUNDLE_LIFECYCLE_BEYOND_NOT_STARTED,
+            BUNDLE_LIFECYCLE_HAS_STARTED,
             viewModel.lifecycleState.value != NOT_STARTED
         )
+        outState.putBoolean(BUNDLE_ONBOARDING_DONE, onboardingDone)
     }
 
     override fun onActivityResult(result: ActivityResult) {
-        // only show next fragment when user went throw onboarding
-        // result doesn't matter as we kill the app when user backs out in onboarding
-        if (viewModel.needToShowDoNotKillMeFragment) {
-            nav.navigate(actionGlobalDoNotKillMeFragment())
-        } else {
-            nav.navigate(actionGlobalStartupFragment())
+        // Only show next fragment when user went through onboarding. We receive RESULT_CANCEL here
+        // when the activity is being relaunched through the app icon and the onboarding activity
+        // gets removed and the existing MainActivity is reused.
+        if (result.resultCode == RESULT_OK) {
+            onboardingDone = true
+            if (viewModel.needToShowDoNotKillMeFragment) {
+                nav.navigate(actionGlobalDoNotKillMeFragment())
+            } else {
+                nav.navigate(actionGlobalStartupFragment())
+            }
         }
     }
 

mailbox-android/src/main/java/org/briarproject/mailbox/android/ui/OnboardingFragment.kt

@@ -19,6 +19,7 @@
 
 package org.briarproject.mailbox.android.ui
 
+import android.app.Activity.RESULT_OK
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
@@ -40,7 +41,7 @@ class Onboarding0Fragment : OnboardingFragment(
     description = R.string.onboarding_0_description,
     bottomButtonText = R.string.button_skip_intro,
     bottomButtonAction = {
-        requireActivity().supportFinishAfterTransition()
+        finishDone()
     },
     backButtonAction = {
         requireActivity().finishAffinity()
@@ -151,6 +152,12 @@ abstract class OnboardingFragment(
 class FinishFragment : Fragment() {
     override fun onResume() {
         super.onResume()
-        requireActivity().supportFinishAfterTransition()
+        finishDone()
     }
+
+}
+
+private fun Fragment.finishDone() {
+    requireActivity().setResult(RESULT_OK)
+    requireActivity().supportFinishAfterTransition()
 }