use non-immediate dispatcher in camera component (#6449)

Author: Zayankovsky

CHANGELOG.md

@@ -16,6 +16,7 @@ Mapbox welcomes participation and contributions from everyone.
 - Introduced `ViewStyleCutomization.compassButtonParams` property to configure compass. [#6395](https://github.com/mapbox/mapbox-navigation-android/pull/6395)
 - Introduced `MapboxExtendableButtonParams.enabled` property to enable/disable a button. [#6395](https://github.com/mapbox/mapbox-navigation-android/pull/6395)
 - Renamed `MapboxAudioGuidance.getInstance()` to `getRegisteredInstance`. Rename `unMute` to `unmute` for audio guidance classes. [#6445](https://github.com/mapbox/mapbox-navigation-android/pull/6445)
+- Fixed an issue with `NavigationView` that prevented camera from going into following state after starting a trip. [#6449](https://github.com/mapbox/mapbox-navigation-android/pull/6449)
 
 ## Mapbox Navigation SDK 2.9.0-alpha.4 - 30 September, 2022
 ### Changelog

libnavui-base/api/current.txt

@@ -45,7 +45,7 @@ package com.mapbox.navigation.ui.base.lifecycle {
   @com.mapbox.navigation.base.ExperimentalPreviewMapboxNavigationAPI public class UIComponent implements com.mapbox.navigation.core.lifecycle.MapboxNavigationObserver {
     ctor public UIComponent();
     method public final kotlinx.coroutines.CoroutineScope getCoroutineScope();
-    method protected final inline <T> void observe(kotlinx.coroutines.flow.Flow<? extends T>, kotlin.jvm.functions.Function2<? super T,? super kotlin.coroutines.Continuation<? super kotlin.Unit>,?> action);
+    method protected final inline <T> void observe(kotlinx.coroutines.flow.Flow<? extends T>, kotlin.coroutines.CoroutineContext context = EmptyCoroutineContext, kotlin.jvm.functions.Function2<? super T,? super kotlin.coroutines.Continuation<? super kotlin.Unit>,?> action);
     method @CallSuper public void onAttached(com.mapbox.navigation.core.MapboxNavigation mapboxNavigation);
     method @CallSuper public void onDetached(com.mapbox.navigation.core.MapboxNavigation mapboxNavigation);
     method public final void setCoroutineScope(kotlinx.coroutines.CoroutineScope);

libnavui-base/src/main/java/com/mapbox/navigation/ui/base/lifecycle/UIComponent.kt

@@ -11,6 +11,8 @@ import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.collect
 import kotlinx.coroutines.launch
+import kotlin.coroutines.CoroutineContext
+import kotlin.coroutines.EmptyCoroutineContext
 
 /**
  * Using the [UIComponent] gives you access to a [coroutineScope] which uses
@@ -42,7 +44,10 @@ open class UIComponent : MapboxNavigationObserver {
         coroutineScope.cancel()
     }
 
-    protected inline fun <T> Flow<T>.observe(crossinline action: suspend (value: T) -> Unit) {
-        coroutineScope.launch { collect(action) }
+    protected inline fun <T> Flow<T>.observe(
+        context: CoroutineContext = EmptyCoroutineContext,
+        crossinline action: suspend (value: T) -> Unit,
+    ) {
+        coroutineScope.launch(context) { collect(action) }
     }
 }

libnavui-dropin/src/main/java/com/mapbox/navigation/dropin/camera/CameraComponent.kt

@@ -22,6 +22,7 @@ import com.mapbox.navigation.ui.maps.camera.lifecycle.NavigationBasicGesturesHan
 import com.mapbox.navigation.ui.maps.camera.transition.NavigationCameraTransitionOptions
 import com.mapbox.navigation.ui.maps.internal.extensions.flowNavigationCameraState
 import com.mapbox.navigation.utils.internal.logD
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.collect
 import kotlinx.coroutines.flow.collectLatest
@@ -127,11 +128,12 @@ internal class CameraComponent constructor(
     }
 
     private fun syncNavigationCameraState() {
-        navigationCamera.flowNavigationCameraState().observe {
+        // using immediate dispatcher causes nested store updates
+        navigationCamera.flowNavigationCameraState().observe(Dispatchers.Main) {
             store.dispatch(SetCameraMode(it.toTargetCameraMode()))
         }
 
-        store.select { it.camera.cameraMode }.observe {
+        store.select { it.camera.cameraMode }.observe(Dispatchers.Main) {
             val currentMode = navigationCamera.state.toTargetCameraMode()
             if (isCameraInitialized && it != currentMode) {
                 when (it) {
@@ -219,7 +221,8 @@ internal class CameraComponent constructor(
                 viewportDataSource.evaluate()
             }
         }
-        coroutineScope.launch {
+        // using immediate dispatcher causes nested store updates
+        coroutineScope.launch(Dispatchers.Main) {
             store.select { it.navigation }.collectLatest { navigationState ->
                 when (navigationState) {
                     NavigationState.FreeDrive -> {

libnavui-maps/src/main/java/com/mapbox/navigation/ui/maps/internal/ui/CameraModeButtonComponent.kt

@@ -34,7 +34,7 @@ class CameraModeButtonComponent(
         super.onAttached(mapboxNavigation)
         val contract = contractProvider.get()
         contract.isVisible.observe { cameraModeButton.isVisible = it }
-        contract.buttonState.observe(cameraModeButton::setState)
+        contract.buttonState.observe { cameraModeButton.setState(it) }
         cameraModeButton.setOnClickListener(contract::onClick)
     }
 

libnavui-maps/src/main/java/com/mapbox/navigation/ui/maps/internal/ui/RecenterButtonComponent.kt

@@ -74,6 +74,6 @@ internal class MapboxRecenterButtonComponentContract(
 
         mapboxNavigation.flowLocationMatcherResult()
             .map { it.enhancedLocation }
-            .observe(location::set)
+            .observe { location.set(it) }
     }
 }