Merge pull request #472 from thgoebel/keep-state

Restore zoom + camera position state when returning to map
mjaakko · Feb 1, 2025 · adf75e1 · adf75e1
2 parents 7d66eb0 + 21a165f
commit adf75e1
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Showing 3 changed files with 22 additions and 15 deletions.
diff --git a/app/src/main/java/xyz/malkki/neostumbler/common/LatLng.kt b/app/src/main/java/xyz/malkki/neostumbler/common/LatLng.kt
@@ -6,4 +6,14 @@ package xyz.malkki.neostumbler.common
 data class LatLng(
     val latitude: Double,
     val longitude: Double
-)
+) {
+    companion object {
+        val ORIGIN = LatLng(0.0, 0.0)
+    }
+
+    fun isOrigin(): Boolean = this == ORIGIN
+
+    fun asMapLibreLatLng(): org.maplibre.android.geometry.LatLng {
+        return org.maplibre.android.geometry.LatLng(latitude, longitude)
+    }
+}
diff --git a/app/src/main/java/xyz/malkki/neostumbler/ui/screens/MapScreen.kt b/app/src/main/java/xyz/malkki/neostumbler/ui/screens/MapScreen.kt
@@ -201,19 +201,16 @@ fun MapScreen(mapViewModel: MapViewModel = viewModel()) {
                     mapView.lifecycle = lifecycle
 
                     mapView.getMapAsync { map ->
-                        if (map.cameraPosition.target == null || (map.cameraPosition.target?.latitude == 0.0 && map.cameraPosition.target?.longitude == 0.0)) {
-                            if (latestReportPosition.value != null) {
-                                map.cameraPosition = CameraPosition.Builder()
-                                    .target(latestReportPosition.value?.let { LatLng(it.latitude, it.longitude) })
-                                    .zoom(10.0)
-                                    .build()
-                            } else {
-                                map.cameraPosition = CameraPosition.Builder()
-                                    .target(LatLng(mapViewModel.mapCenter.value.latitude, mapViewModel.mapCenter.value.longitude))
-                                    .zoom(mapViewModel.zoom.value)
-                                    .build()
-                            }
+                        // Call repeatedly in update() because latestReportPosition may not be available in factory()
+                        val target = if (mapViewModel.mapCenter.value.isOrigin()) {
+                            latestReportPosition.value
+                        } else {
+                            mapViewModel.mapCenter.value
                         }
+                        map.cameraPosition = CameraPosition.Builder()
+                            .target(target?.asMapLibreLatLng())
+                            .zoom(mapViewModel.zoom.value)
+                            .build()
 
                         if (myLocation.value != null && map.locationComponent.isLocationComponentActivated) {
                             map.locationComponent.forceLocationUpdate(myLocation.value!!.location)

diff --git a/app/src/main/java/xyz/malkki/neostumbler/ui/viewmodel/MapViewModel.kt b/app/src/main/java/xyz/malkki/neostumbler/ui/viewmodel/MapViewModel.kt
@@ -74,11 +74,11 @@ class MapViewModel(application: Application) : AndroidViewModel(application) {
 
     private val showMyLocation = MutableStateFlow(getApplication<StumblerApplication>().checkMissingPermissions(Manifest.permission.ACCESS_COARSE_LOCATION).isEmpty())
 
-    private val _mapCenter = MutableStateFlow<LatLng>(LatLng(0.0, 0.0))
+    private val _mapCenter = MutableStateFlow<LatLng>(LatLng.ORIGIN)
     val mapCenter: StateFlow<LatLng>
         get() = _mapCenter.asStateFlow()
 
-    private val _zoom = MutableStateFlow(5.0)
+    private val _zoom = MutableStateFlow(12.0)
     val zoom: StateFlow<Double>
         get() = _zoom.asStateFlow()