fix more issues switching the data source, esp. on Android Auto

app/src/google/java/net/vonforst/evmap/auto/MapScreen.kt

@@ -13,7 +13,10 @@ import androidx.car.app.hardware.info.EnergyLevel
 import androidx.car.app.model.*
 import androidx.core.content.ContextCompat
 import androidx.core.graphics.drawable.IconCompat
-import androidx.lifecycle.*
+import androidx.lifecycle.DefaultLifecycleObserver
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.lifecycleScope
 import com.car2go.maps.model.LatLng
 import kotlinx.coroutines.*
 import net.vonforst.evmap.BuildConfig
@@ -30,6 +33,7 @@ import net.vonforst.evmap.storage.PreferenceDataSource
 import net.vonforst.evmap.ui.availabilityText
 import net.vonforst.evmap.ui.getMarkerTint
 import net.vonforst.evmap.utils.distanceBetween
+import net.vonforst.evmap.viewmodel.await
 import net.vonforst.evmap.viewmodel.awaitFinished
 import net.vonforst.evmap.viewmodel.filtersWithValue
 import net.vonforst.evmap.viewmodel.getFilterValues
@@ -173,7 +177,9 @@ class MapScreen(ctx: CarContext, val session: EVMapSession) :
                             ).setTint(CarColor.DEFAULT).build()
                         )
                         .setOnClickListener {
-                            screenManager.push(SettingsScreen(carContext))
+                            screenManager.pushForResult(SettingsScreen(carContext)) {
+                                repo.api.value = createApi(prefs.dataSource, carContext)
+                            }
                             session.mapScreen = null
                         }
                         .build())
@@ -308,7 +314,6 @@ class MapScreen(ctx: CarContext, val session: EVMapSession) :
 
     private fun loadChargers() {
         val location = location ?: return
-        val filters = filtersWithValue.value ?: return
 
         val searchLocation =
             prefs.placeSearchResultAndroidAuto ?: LatLng.fromLocation(location)
@@ -316,6 +321,8 @@ class MapScreen(ctx: CarContext, val session: EVMapSession) :
 
         updateCoroutine = lifecycleScope.launch {
             try {
+                val filters = filtersWithValue.await()
+
                 // load chargers
                 if (filterStatus.value == FILTERS_FAVORITES) {
                     chargers =
@@ -373,9 +380,7 @@ class MapScreen(ctx: CarContext, val session: EVMapSession) :
         // Reloading chargers in onStart does not seem to count towards content limit.
         // So let's do this so the user gets fresh chargers when re-entering the app.
         invalidate()
-        filtersWithValue.observe(this@MapScreen) {
-            loadChargers()
-        }
+        loadChargers()
     }
 
     private fun setupListeners() {

app/src/main/java/net/vonforst/evmap/storage/ChargeLocationsDao.kt

@@ -13,10 +13,7 @@ import net.vonforst.evmap.api.StringProvider
 import net.vonforst.evmap.api.goingelectric.GEReferenceData
 import net.vonforst.evmap.api.goingelectric.GoingElectricApiWrapper
 import net.vonforst.evmap.api.openchargemap.OpenChargeMapApiWrapper
-import net.vonforst.evmap.model.ChargeLocation
-import net.vonforst.evmap.model.ChargepointListItem
-import net.vonforst.evmap.model.FilterValues
-import net.vonforst.evmap.model.ReferenceData
+import net.vonforst.evmap.model.*
 import net.vonforst.evmap.viewmodel.Resource
 import net.vonforst.evmap.viewmodel.await
 
@@ -39,7 +36,7 @@ class ChargeLocationsRepository(
 ) {
     val api = MutableLiveData<ChargepointApi<ReferenceData>>().apply { value = api }
 
-    private val apiAndReferenceData = this.api.switchMap { api ->
+    val referenceData = this.api.switchMap { api ->
         when (api) {
             is GoingElectricApiWrapper -> {
                 GEReferenceDataRepository(
@@ -47,7 +44,7 @@ class ChargeLocationsRepository(
                     scope,
                     db.geReferenceDataDao(),
                     prefs
-                ).getReferenceData().map { api to it }
+                ).getReferenceData()
             }
             is OpenChargeMapApiWrapper -> {
                 OCMReferenceDataRepository(
@@ -55,14 +52,13 @@ class ChargeLocationsRepository(
                     scope,
                     db.ocmReferenceDataDao(),
                     prefs
-                ).getReferenceData().map { api to it }
+                ).getReferenceData()
             }
             else -> {
                 throw RuntimeException("no reference data implemented")
             }
         }
     }
-    val referenceData = apiAndReferenceData.map { it.second }
 
     private val chargeLocationsDao = db.chargeLocationsDao()
 
@@ -72,8 +68,8 @@ class ChargeLocationsRepository(
         filters: FilterValues?
     ): LiveData<Resource<List<ChargepointListItem>>> {
         return liveData {
-            val (api, refData) = apiAndReferenceData.await()
-            val result = api.getChargepoints(refData, bounds, zoom, filters)
+            val refData = referenceData.await()
+            val result = api.value!!.getChargepoints(refData, bounds, zoom, filters)
 
             emit(result)
         }
@@ -86,8 +82,8 @@ class ChargeLocationsRepository(
         filters: FilterValues?
     ): LiveData<Resource<List<ChargepointListItem>>> {
         return liveData {
-            val (api, refData) = apiAndReferenceData.await()
-            val result = api.getChargepointsRadius(refData, location, radius, zoom, filters)
+            val refData = referenceData.await()
+            val result = api.value!!.getChargepointsRadius(refData, location, radius, zoom, filters)
 
             emit(result)
         }
@@ -97,18 +93,20 @@ class ChargeLocationsRepository(
         id: Long
     ): LiveData<Resource<ChargeLocation>> {
         return liveData {
-            val (api, refData) = apiAndReferenceData.await()
-            val result = api.getChargepointDetail(refData, id)
+            val refData = referenceData.await()
+            val result = api.value!!.getChargepointDetail(refData, id)
             emit(result)
         }
     }
 
-    fun getFilters(sp: StringProvider) = apiAndReferenceData.map { (api, refData) ->
-        api.getFilters(refData, sp)
+    fun getFilters(sp: StringProvider) = MediatorLiveData<List<Filter<FilterValue>>>().apply {
+        addSource(referenceData) { refData: ReferenceData? ->
+            refData?.let { value = api.value!!.getFilters(refData, sp) }
+        }
     }
 
     val chargeCardMap by lazy {
-        apiAndReferenceData.map { (_, refData) ->
+        referenceData.map { refData: ReferenceData? ->
             if (refData is GEReferenceData) {
                 refData.chargecards.associate {
                     it.id to it.convert()

app/src/main/java/net/vonforst/evmap/storage/GEReferenceDataDao.kt

@@ -87,6 +87,7 @@ class GEReferenceDataRepository(
         val networks = dao.getAllNetworks()
         val chargeCards = dao.getAllChargeCards()
         return MediatorLiveData<GEReferenceData>().apply {
+            value = null
             listOf(chargeCards, networks, plugs).map { source ->
                 addSource(source) { _ ->
                     val p = plugs.value ?: return@addSource

app/src/main/java/net/vonforst/evmap/storage/OCMReferenceDataDao.kt

@@ -79,6 +79,7 @@ class OCMReferenceDataRepository(
         val countries = dao.getAllCountries()
         val operators = dao.getAllOperators()
         return MediatorLiveData<OCMReferenceData>().apply {
+            value = null
             listOf(countries, connectionTypes, operators).map { source ->
                 addSource(source) { _ ->
                     val ct = connectionTypes.value