Avoid updating the UI every seconds

vector/src/main/java/im/vector/app/features/MainActivity.kt

@@ -142,23 +142,27 @@ class MainActivity : VectorBaseActivity<ActivityMainBinding>(), UnlockedActivity
     }
 
     private fun renderState(state: StartAppViewState) {
-        if (state.duration > 0) {
+        if (state.mayBeLongToProcess) {
             views.status.setText(R.string.updating_your_data)
         }
-        views.status.isVisible = state.duration > 0
+        views.status.isVisible = state.mayBeLongToProcess
-        if (state.duration == 1L && startAppViewModel.shouldStartApp()) {
-            // Start foreground service, because the operation may take a while
-            val intent = Intent(this, StartAppAndroidService::class.java)
-            ContextCompat.startForegroundService(this, intent)
-        }
     }
 
     private fun handleViewEvents(event: StartAppViewEvent) {
         when (event) {
+            StartAppViewEvent.StartForegroundService -> handleStartForegroundService()
             StartAppViewEvent.AppStarted -> handleAppStarted()
         }
     }
 
+    private fun handleStartForegroundService() {
+        if (startAppViewModel.shouldStartApp()) {
+            // Start foreground service, because the operation may take a while
+            val intent = Intent(this, StartAppAndroidService::class.java)
+            ContextCompat.startForegroundService(this, intent)
+        }
+    }
+
     private fun handleAppStarted() {
         if (intent.hasExtra(EXTRA_NEXT_INTENT)) {
             // Start the next Activity

vector/src/main/java/im/vector/app/features/start/StartAppViewEvent.kt

@@ -19,5 +19,13 @@ package im.vector.app.features.start
 import im.vector.app.core.platform.VectorViewEvents
 
 sealed interface StartAppViewEvent : VectorViewEvents {
+    /**
+     * Will be sent if the process is taking more than 1 second.
+     */
+    object StartForegroundService : StartAppViewEvent
+
+    /**
+     * Will be sent when the current Session has been set.
+     */
     object AppStarted : StartAppViewEvent
 }

vector/src/main/java/im/vector/app/features/start/StartAppViewModel.kt

@@ -24,10 +24,8 @@ import im.vector.app.core.di.ActiveSessionSetter
 import im.vector.app.core.di.MavericksAssistedViewModelFactory
 import im.vector.app.core.di.hiltMavericksViewModelFactory
 import im.vector.app.core.platform.VectorViewModel
-import im.vector.lib.core.utils.flow.tickerFlow
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.delay
-import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.launch
 import kotlin.time.Duration.Companion.seconds
 
@@ -54,7 +52,7 @@ class StartAppViewModel @AssistedInject constructor(
     }
 
     private fun handleStartApp() {
-        startTimer()
+        handleLongProcessing()
         viewModelScope.launch(Dispatchers.IO) {
             // This can take time because of DB migration(s), so do it in a background task.
             activeSessionSetter.tryToSetActiveSession(startSync = true)
@@ -62,12 +60,11 @@ class StartAppViewModel @AssistedInject constructor(
         }
     }
 
-    private fun startTimer() {
+    private fun handleLongProcessing() {
-        setState { copy(duration = 0) }
+        viewModelScope.launch(Dispatchers.Default) {
-        tickerFlow(viewModelScope, 1.seconds.inWholeMilliseconds)
+            delay(1.seconds.inWholeMilliseconds)
-                .onEach {
+            setState { copy(mayBeLongToProcess = true) }
-                    setState { copy(duration = duration + 1) }
+            _viewEvents.post(StartAppViewEvent.StartForegroundService)
-                }
+        }
-                .launchIn(viewModelScope)
     }
 }

vector/src/main/java/im/vector/app/features/start/StartAppViewState.kt

@@ -19,5 +19,5 @@ package im.vector.app.features.start
 import com.airbnb.mvrx.MavericksState
 
 data class StartAppViewState(
-        val duration: Long = 0
+        val mayBeLongToProcess: Boolean = false
 ) : MavericksState