Merge branch 'pr-5' into try-pr-5

Fix map loading by drawing a virtual display.

gearslip/src/main/java/app/seb3thehacker/gearslip/car/CarAppStage.kt

@@ -89,6 +89,28 @@ private fun AppSurface(
         }
     }
 
+    // A fresh SurfaceView - and so a fresh Surface - for every size, the way Android Auto hands an
+    // app a new surface rather than resizing the old one. A resized SurfaceView keeps the same
+    // BufferQueue, and apps that draw through their own VirtualDisplay build the
+    // new one on it before releasing the old: the old display's disconnect then takes the new one's
+    // connection with it and the map freezes for good. The nav bar hiding for the search keyboard
+    // and the lyrics pane opening both resize this area.
+    androidx.compose.foundation.layout.BoxWithConstraints(modifier) {
+        androidx.compose.runtime.key(constraints.maxWidth, constraints.maxHeight) {
+            SurfaceHost(connection, frame, onSize = { size = it }, Modifier.fillMaxSize())
+        }
+    }
+
+    DisposableEffect(connection) { onDispose { connection.detachSurface() } }
+}
+
+@Composable
+private fun SurfaceHost(
+    connection: CarAppConnection,
+    frame: CarEnvironment.Frame,
+    onSize: (Pair<Int, Int>) -> Unit,
+    modifier: Modifier,
+) {
     AndroidView(
         modifier = modifier
             .pointerInput(connection) {
@@ -114,20 +136,20 @@ private fun AppSurface(
                         height: Int,
                     ) {
                         GearslipLog.i("stage: surface ready at ${width}x$height")
-                        size = width to height
+                        onSize(width to height)
                         connection.attachSurface(holder.surface, width, height, frame.densityDpi)
                     }
 
                     override fun surfaceDestroyed(holder: SurfaceHolder) {
                         GearslipLog.i("stage: surface destroyed")
-                        connection.detachSurface()
+                        // Only this view's own surface: a replaced view's teardown can land after
+                        // its successor has already lent the app a new one.
+                        connection.detachSurface(holder.surface)
                     }
                 })
             }
         },
     )
-
-    DisposableEffect(connection) { onDispose { connection.detachSurface() } }
 }
 
 @Composable

gearslip/src/main/java/app/seb3thehacker/gearslip/host/CarAppConnection.kt

@@ -139,8 +139,19 @@ class CarAppConnection(private val context: Context) {
             // Replaced by another connect (or a disconnect) while waiting on the location service.
             if (binding !== connection) return@bind
             var bindError: Throwable? = null
+            val flags = Context.BIND_AUTO_CREATE or LocationKeepAlive.BIND_INCLUDE_CAPABILITIES
             val bound = runCatching {
-                context.bindService(intent, connection, Context.BIND_AUTO_CREATE or LocationKeepAlive.BIND_INCLUDE_CAPABILITIES)
+                // Without BIND_FOREGROUND_SERVICE, an app bound by a foreground service (which is
+                // all Gearslip is once the phone screen leaves it) only reaches "important
+                // foreground", and that state loses network under Doze and background network
+                // restrictions: the map and GPS keep working while search and routing go dead.
+                // In the preview Gearslip is the top app, which hides this. Retried without the
+                // flag in case a build of Android refuses it from an unprivileged caller.
+                runCatching { context.bindService(intent, connection, flags or BIND_FOREGROUND_SERVICE) }
+                    .getOrElse {
+                        GearslipLog.w("host: foreground binding refused (${it.message}); binding without it")
+                        context.bindService(intent, connection, flags)
+                    }
             }.getOrElse {
                 GearslipLog.e("bindService threw for ${app.component}", it)
                 bindError = it
@@ -428,10 +439,14 @@ class CarAppConnection(private val context: Context) {
         }
     }
 
-    /** Takes the Surface back, e.g. when the SurfaceView goes away. */
-    fun detachSurface() {
+    /**
+     * Takes the Surface back, e.g. when the SurfaceView goes away. With [surface], only if that is
+     * still the one lent - a replaced view's teardown must not take back its successor's.
+     */
+    fun detachSurface(surface: Surface? = null) {
         main.post {
             val current = lent ?: return@post
+            if (surface != null && current.surface !== surface) return@post
             lent = null
             sendSurfaceDestroyed(current)
             update { it.copy(surfaceAttached = false) }
@@ -714,5 +729,8 @@ class CarAppConnection(private val context: Context) {
     private companion object {
         /** The newest template API this host claims to understand. */
         const val HOST_API_LEVEL = CarAppApiLevels.LEVEL_8
+
+        /** Context.BIND_FOREGROUND_SERVICE; the constant itself is hidden from the SDK. */
+        const val BIND_FOREGROUND_SERVICE = 0x04000000
     }
 }