make VehicleDataScreen request permissions and work correctly

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

@@ -11,7 +11,6 @@ import net.vonforst.evmap.R
  */
 class PermissionScreen(
     ctx: CarContext,
-    val session: EVMapSession,
     @StringRes val message: Int,
     val permissions: List<String>
 ) : Screen(ctx) {

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

@@ -1,43 +1,102 @@
 package net.vonforst.evmap.auto
 
+import android.content.pm.PackageManager
+import android.os.Handler
+import android.os.Looper
 import androidx.car.app.CarContext
 import androidx.car.app.Screen
 import androidx.car.app.hardware.CarHardwareManager
-import androidx.car.app.hardware.common.OnCarDataAvailableListener
 import androidx.car.app.hardware.info.EnergyLevel
-import androidx.car.app.model.GridItem
-import androidx.car.app.model.GridTemplate
-import androidx.car.app.model.ItemList
-import androidx.car.app.model.Template
+import androidx.car.app.hardware.info.Model
+import androidx.car.app.model.*
 import androidx.core.content.ContextCompat
+import net.vonforst.evmap.R
 
-class VehicleDataScreen(ctx: CarContext) : Screen(ctx), OnCarDataAvailableListener<EnergyLevel> {
-    val hardwareMan = ctx.getCarService(CarContext.HARDWARE_SERVICE) as CarHardwareManager
-    var energyLevel: EnergyLevel? = null
+class VehicleDataScreen(ctx: CarContext) : Screen(ctx) {
+    private val hardwareMan = ctx.getCarService(CarContext.HARDWARE_SERVICE) as CarHardwareManager
+    private var model: Model? = null
+    private var energyLevel: EnergyLevel? = null
 
-    init {
-        hardwareMan.carInfo.addEnergyLevelListener(ContextCompat.getMainExecutor(ctx), this)
-    }
+    private val permissions = listOf(
+        "com.google.android.gms.permission.CAR_FUEL"
+    )
 
     override fun onGetTemplate(): Template {
-        val energy = energyLevel ?: return GridTemplate.Builder().setLoading(true).build()
-
-        return GridTemplate.Builder().setSingleList(
-            ItemList.Builder().apply {
-                energy.batteryPercent.value?.let { percent ->
-                    addItem(
-                        GridItem.Builder()
-                            .setTitle("Battery")
-                            .setText("%.1f".format(percent))
-                            .build()
+        if (permissionsGranted()) {
+            setupListeners()
+        } else {
+            Handler(Looper.getMainLooper()).post {
+                screenManager.pushForResult(
+                    PermissionScreen(
+                        carContext,
+                        R.string.auto_location_permission_needed,
+                        permissions
                     )
+                ) {
+                    setupListeners()
                 }
-            }.build()
-        ).build()
+            }
+        }
+
+        val energyLevel = energyLevel
+        val model = model
+
+        return GridTemplate.Builder().apply {
+            setTitle(
+                if (model != null && model.manufacturer.value != null && model.name.value != null) {
+                    "${model.manufacturer.value} ${model.name.value}"
+                } else {
+                    carContext.getString(R.string.auto_vehicle_data)
+                }
+            )
+            setHeaderAction(Action.BACK)
+            if (!permissionsGranted()) {
+                setLoading(true)
+            } else {
+                setSingleList(
+                    ItemList.Builder().apply {
+                        addItem(
+                            GridItem.Builder().apply {
+                                setTitle("Battery")
+                                energyLevel?.batteryPercent?.value?.let { percent ->
+                                    setText("%.1f".format(percent))
+                                    setImage(CarIcon.APP_ICON)
+                                } ?: setLoading(true)
+                            }.build()
+                        )
+                        addItem(
+                            GridItem.Builder().apply {
+                                setTitle("Fuel")
+                                energyLevel?.fuelPercent?.value?.let { percent ->
+                                    setText("%.1f".format(percent))
+                                    setImage(CarIcon.APP_ICON)
+                                } ?: setLoading(true)
+                            }.build()
+                        )
+                    }.build()
+                )
+            }
+        }.build()
     }
 
-    override fun onCarDataAvailable(data: EnergyLevel) {
-        this.energyLevel = energyLevel
-        invalidate()
+    private fun setupListeners() {
+        val exec = ContextCompat.getMainExecutor(carContext)
+        hardwareMan.carInfo.addEnergyLevelListener(exec) {
+            this.energyLevel = it
+            invalidate()
+        }
+
+        hardwareMan.carInfo.fetchModel(exec) {
+            this.model = it
+            invalidate()
+        }
     }
+
+    private fun permissionsGranted(): Boolean =
+        permissions.all {
+            ContextCompat.checkSelfPermission(
+                carContext,
+                it
+            ) == PackageManager.PERMISSION_GRANTED
+        }
 }

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

@@ -22,7 +22,6 @@ class WelcomeScreen(ctx: CarContext, val session: EVMapSession) : Screen(ctx), L
                 screenManager.pushForResult(
                     PermissionScreen(
                         carContext,
-                        session,
                         R.string.auto_location_permission_needed,
                         listOf(Manifest.permission.ACCESS_FINE_LOCATION)
                     )

app/src/google/res/values-de/values.xml

@@ -15,6 +15,7 @@
     <string name="open_in_app">In App öffnen</string>
     <string name="opened_on_phone">Auf dem Telefon geöffnet</string>
     <string name="auto_location_permission_needed">Um EVMap auf Android Auto zu nutzen, braucht die App Zugriff auf deinen Standort.</string>
+    <string name="auto_vehicle_data_permission_needed">Für diese Funktion benötigt EVMap Zugriff auf Daten deines Fahrzeugs.</string>
     <string name="grant_on_phone">Auf Telefon zulassen</string>
     <string name="auto_chargers_closeby">In der Nähe</string>
     <string name="auto_favorites">Favoriten</string>

app/src/google/res/values/values.xml

@@ -25,6 +25,7 @@
     <string name="open_in_app">Open in app</string>
     <string name="opened_on_phone">Opened on phone</string>
     <string name="auto_location_permission_needed">To run EVMap on Android Auto, you need to grant access to your location.</string>
+    <string name="auto_vehicle_data_permission_needed">For this feature, EVMap needs access to your vehicle data.</string>
     <string name="grant_on_phone">Grant on phone</string>
     <string name="auto_chargers_closeby">Nearby chargers</string>
     <string name="auto_favorites">Favorites</string>