Keep the map design across configuration changes

build.gradle.kts

@@ -97,6 +97,15 @@ dependencies {
             ),
         ),
     )
+    // 実機テスト（HereMapViewSaverTest）は MapScheme などを実行時に読むので、テスト APK には同梱する。
+    androidTestImplementation(
+        fileTree(
+            mapOf(
+                "dir" to rootDir.resolve("libs").toString(),
+                "include" to arrayOf("heresdk*.jar", "heresdk*.aar"),
+            ),
+        ),
+    )
     if (findProject(":android-sdk-compose") != null) {
         api(project(":android-sdk-compose"))
     } else {

src/androidTest/java/com/mapconductor/here/HereMapViewSaverTest.kt

@@ -0,0 +1,85 @@
+package com.mapconductor.here
+
+import androidx.compose.runtime.saveable.Saver
+import androidx.compose.runtime.saveable.SaverScope
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.here.sdk.mapview.MapScheme
+import com.mapconductor.core.features.GeoPoint
+import com.mapconductor.core.map.AttributionRule
+import com.mapconductor.core.map.MapCameraPosition
+import com.mapconductor.core.map.MapUISettings
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertSame
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import android.os.Bundle
+import android.os.Parcel
+
+/**
+ * 回転などの構成変更で state が [HereMapViewSaver] を通って作り直されても、デザイン（id・
+ * attributionRules ほか）と uiSettings・カメラが落ちないこと。Bundle は実機の Parcel を一度通す。
+ */
+@RunWith(AndroidJUnit4::class)
+class HereMapViewSaverTest {
+    private val rules =
+        listOf(AttributionRule("© test"), AttributionRule("© ranged", minZoom = 3, maxZoom = 15))
+
+    private val camera =
+        MapCameraPosition(
+            position = GeoPoint(21.38, -157.93),
+            zoom = 12.0,
+            bearing = 20.0,
+            tilt = 10.0,
+        )
+
+    @Test
+    fun keepsCustomDesignWithAttributionRules() {
+        val design = HereMapDesign.Custom(MapScheme.SATELLITE, rules)
+        val state = HereViewState(id = "here-1", mapDesignType = design, cameraPosition = camera)
+        state.uiSettings = MapUISettings(rotateGesture = false, tiltGesture = false)
+
+        val restored = roundTrip(HereMapViewSaver().createSaver(), state)
+
+        val actual = restored.mapDesignType
+        assertTrue(actual is HereMapDesign.Custom)
+        assertEquals(MapScheme.SATELLITE, actual.id)
+        assertEquals(rules, actual.attributionRules)
+        assertCommon(restored, "here-1")
+    }
+
+    @Test
+    fun keepsPresetDesignAsTheSameObject() {
+        val state = HereViewState(id = "here-2", mapDesignType = HereMapDesign.LiteNight)
+        assertSame(HereMapDesign.LiteNight, roundTrip(HereMapViewSaver().createSaver(), state).mapDesignType)
+    }
+
+    private fun assertCommon(
+        restored: com.mapconductor.core.map.MapViewStateInterface<*>,
+        id: String,
+    ) {
+        assertEquals(id, restored.id)
+        assertEquals(false, restored.uiSettings.rotateGesture)
+        assertEquals(false, restored.uiSettings.tiltGesture)
+        assertEquals(true, restored.uiSettings.scrollGesture)
+        assertEquals(12.0, restored.cameraPosition.zoom, 1e-9)
+        assertEquals(20.0, restored.cameraPosition.bearing, 1e-9)
+        assertEquals(21.38, restored.cameraPosition.position.latitude, 1e-9)
+    }
+
+    private fun <T : Any> roundTrip(
+        saver: Saver<T, Bundle>,
+        value: T,
+    ): T {
+        val saved = with(saver) { SaverScope { true }.save(value) }!!
+        // 一度 Parcel に書いて読み戻す（プロセスが落ちたあとの復元と同じ経路）。
+        val parcel = Parcel.obtain()
+        try {
+            parcel.writeBundle(saved)
+            parcel.setDataPosition(0)
+            return saver.restore(parcel.readBundle(javaClass.classLoader)!!)!!
+        } finally {
+            parcel.recycle()
+        }
+    }
+}

src/main/java/com/mapconductor/here/HereMapView.kt

@@ -149,6 +149,10 @@ fun HereMapView(
             controller.setMapClickListener(onMapClick)
             controller.setMapLongClickListener(onMapLongClick)
             state.setController(controller)
+            // コントローラの既定値（NormalDay）のままリスナーを繋ぐと、それが state へ返り、
+            // アプリが渡した（あるいは回転後に復元した）デザインが NormalDay に化ける。
+            // 下の loadScene は state のデザインを読むので、その前に揃えておく。
+            controller.mapDesignType = state.mapDesignType
             controller.setMapDesignTypeChangeListener(state::onMapDesignTypeChange)
             cameraRestriction?.let { controller.setCameraRestriction(it) }
 

src/main/java/com/mapconductor/here/HereMapViewController.kt

@@ -238,7 +238,7 @@ class HereMapViewController(
         polygonController.clickListener = listener
     }
 
-    private var mapDesignType: HereMapDesignType = HereMapDesign.NormalDay
+    internal var mapDesignType: HereMapDesignType = HereMapDesign.NormalDay
     private var mapDesignTypeChangeListener: HereMapDesignTypeChangeHandler? = null
 
     override fun applyUISettings(settings: MapUISettings) {

src/main/java/com/mapconductor/here/HereViewStateImpl.kt

@@ -5,12 +5,14 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.saveable.rememberSaveable
+import com.here.sdk.mapview.MapScheme
 import com.mapconductor.compose.map.BaseMapViewSaver
 import com.mapconductor.core.map.MapCameraPosition
 import com.mapconductor.core.map.MapCameraPositionInterface
 import com.mapconductor.core.map.MapPaddings
 import com.mapconductor.core.map.MapPaddingsInterface
 import com.mapconductor.core.map.MapViewState
+import com.mapconductor.core.map.MapViewStateBundle
 import com.mapconductor.core.map.MapViewStateInterface
 import java.util.UUID
 import android.app.Activity
@@ -60,28 +62,49 @@ class HereMapViewSaver : BaseMapViewSaver<HereViewState>() {
         state: HereViewState,
         bundle: Bundle,
     ) {
-        bundle.putInt("id", state.mapDesignType.getValue().value)
+        val design = state.mapDesignType
+        val scheme = design.getValue().value
+        bundle.putInt("id", scheme)
+        // 定義済み（NormalDay など）以外は Custom として戻す。id だけだと Custom の
+        // attributionRules が落ちる。
+        bundle.putBoolean(KEY_CUSTOM, design !== presetOrNull(scheme))
+        MapViewStateBundle.putAttributionRules(bundle, design.attributionRules)
     }
 
     override fun createState(
         stateId: String,
         mapDesignBundle: Bundle?,
         cameraPosition: MapCameraPosition,
-    ): HereViewState =
-        HereViewState(
+    ): HereViewState {
+        val scheme = mapDesignBundle?.getInt("id", HereMapDesign.NormalDay.id.value) ?: HereMapDesign.NormalDay.id.value
+        val preset = presetOrNull(scheme)
+        val mapScheme = MapScheme.values().firstOrNull { it.value == scheme }
+        val design =
+            if ((mapDesignBundle?.getBoolean(KEY_CUSTOM) == true || preset == null) && mapScheme != null) {
+                HereMapDesign.Custom(
+                    id = mapScheme,
+                    attributionRules = MapViewStateBundle.getAttributionRules(mapDesignBundle),
+                )
+            } else {
+                preset ?: HereMapDesign.NormalDay
+            }
+        return HereViewState(
             id = stateId,
-            mapDesignType =
-                HereMapDesign.create(
-                    id = mapDesignBundle?.getInt("id") ?: HereMapDesign.NormalDay.id.value,
-                ),
+            mapDesignType = design,
             cameraPosition = cameraPosition,
         )
+    }
+
+    private fun presetOrNull(scheme: Int): HereMapDesign? = runCatching { HereMapDesign.create(scheme) }.getOrNull()
 
     override fun getCameraPaddings(): MapPaddingsInterface? = MapPaddings.Zeros
 
     override fun getStateId(state: HereViewState): String = state.id
 }
 
+// 公開 API の門番（javap）にコンパニオンの定数が載らないよう、ファイル private にする。
+private const val KEY_CUSTOM = "custom"
+
 @Composable
 fun rememberHereMapViewState(
     mapDesign: HereMapDesign = HereMapDesign.NormalDay,