map node zooming works better

app/src/main/java/com/geeksville/mesh/MainActivity.kt

@@ -134,10 +134,7 @@ class MainActivity : AppCompatActivity(), Logging,
             "Messages",
             R.drawable.ic_twotone_message_24,
             ComposeFragment("Messages", 1) { MessagesContent() }),
-        TabInfo(
-            "Settings",
-            R.drawable.ic_twotone_settings_applications_24,
-            ComposeFragment("Settings", 2) { SettingsContent() }),
+
         TabInfo(
             "Users",
             R.drawable.ic_twotone_people_24,
@@ -150,7 +147,11 @@ class MainActivity : AppCompatActivity(), Logging,
             "Map",
             R.drawable.ic_twotone_map_24,
             MapFragment()
-        )
+        ),
+        TabInfo(
+            "Settings",
+            R.drawable.ic_twotone_settings_applications_24,
+            BTScanFragment("Settings", 2) { SettingsContent() })
     )
 
     private
@@ -301,7 +302,7 @@ class MainActivity : AppCompatActivity(), Logging,
         val pager = findViewById<ViewPager2>(R.id.pager)
         pager.adapter = tabsAdapter
         TabLayoutMediator(tab_layout, pager) { tab, position ->
-            tab.text = tabInfos[position].text
+            // tab.text = tabInfos[position].text // I think it looks better with icons only
             tab.icon = getDrawable(tabInfos[position].icon)
         }.attach()
     }
@@ -539,7 +540,6 @@ class MainActivity : AppCompatActivity(), Logging,
     }
 
     override fun onStop() {
-        ScanState.stopScan()
         unregisterMeshReceiver() // No point in receiving updates while the GUI is gone, we'll get them when the user launches the activity
         unbindMeshService()
 

app/src/main/java/com/geeksville/mesh/ui/BTScanScreen.kt

@@ -65,6 +65,15 @@ data class BTScanEntry(val name: String, val macAddress: String, val bonded: Boo
 }
 
 
+class BTScanFragment(screenName: String, id: Int, private val content: @Composable() () -> Unit) :
+    ComposeFragment(screenName, id, content) {
+
+    override fun onStop() {
+        ScanState.stopScan()
+        super.onStop()
+    }
+}
+
 @Composable
 fun BTScanScreen() {
     val context = ContextAmbient.current
@@ -146,11 +155,6 @@ fun BTScanScreen() {
                 ScanState.callback = scanCallback
             }
         }
-
-        onDispose {
-            ScanState.debug("BTScan component deactivated")
-            ScanState.stopScan()
-        }
     }
 
     Column {

app/src/main/java/com/geeksville/mesh/ui/ComposeFragment.kt

@@ -7,7 +7,6 @@ import android.view.ViewGroup
 import android.widget.FrameLayout
 import androidx.compose.Composable
 import androidx.ui.core.setContent
-import com.geeksville.android.Logging
 
 fun androidx.fragment.app.Fragment.setComposable(
     id: Int,
@@ -27,9 +26,12 @@ fun androidx.fragment.app.Fragment.setComposable(
     }
 
 
-class ComposeFragment(screenName: String, id: Int, private val content: @Composable() () -> Unit) :
-    ScreenFragment(screenName),
-    Logging {
+open class ComposeFragment(
+    screenName: String,
+    id: Int,
+    private val content: @Composable() () -> Unit
+) :
+    ScreenFragment(screenName) {
     override fun onCreateView(
         inflater: LayoutInflater, container: ViewGroup?,
         savedInstanceState: Bundle?

app/src/main/java/com/geeksville/mesh/ui/MapFragment.kt

@@ -17,6 +17,7 @@ import com.mapbox.mapboxsdk.camera.CameraUpdateFactory
 import com.mapbox.mapboxsdk.geometry.LatLng
 import com.mapbox.mapboxsdk.geometry.LatLngBounds
 import com.mapbox.mapboxsdk.maps.MapView
+import com.mapbox.mapboxsdk.maps.MapboxMap
 import com.mapbox.mapboxsdk.maps.Style
 import com.mapbox.mapboxsdk.style.expressions.Expression
 import com.mapbox.mapboxsdk.style.layers.Property
@@ -28,7 +29,81 @@ import com.mapbox.mapboxsdk.style.sources.GeoJsonSource
 
 
 class MapFragment : ScreenFragment("Map"), Logging {
-    
+
+    private val nodeSourceId = "node-positions"
+    private val nodeLayerId = "node-layer"
+    private val labelLayerId = "label-layer"
+    private val markerImageId = "my-marker-image"
+
+    private val nodePositions = GeoJsonSource(nodeSourceId)
+
+    private val nodeLayer = SymbolLayer(nodeLayerId, nodeSourceId).withProperties(
+        iconImage(markerImageId),
+        iconAnchor(Property.ICON_ANCHOR_BOTTOM),
+        iconAllowOverlap(true)
+    )
+
+    private val labelLayer = SymbolLayer(labelLayerId, nodeSourceId).withProperties(
+        textField(Expression.get("name")),
+        textSize(12f),
+        textColor(Color.RED),
+        textVariableAnchor(arrayOf(TEXT_ANCHOR_TOP)),
+        textJustify(TEXT_JUSTIFY_AUTO),
+        textAllowOverlap(true)
+    )
+
+    private fun nodesWithPosition() = NodeDB.nodes.values.filter { it.validPosition != null }
+
+    /**
+     * Using the latest nodedb, generate geojson features
+     */
+    private fun getCurrentNodes(): FeatureCollection {
+        // Find all nodes with valid locations
+
+        val locations = nodesWithPosition().map { node ->
+            val p = node.position!!
+            debug("Showing on map: $node")
+
+            val f = Feature.fromGeometry(
+                Point.fromLngLat(
+                    p.longitude,
+                    p.latitude
+                )
+            )
+            node.user?.let {
+                f.addStringProperty("name", it.longName)
+            }
+            f
+        }
+
+        return FeatureCollection.fromFeatures(locations)
+    }
+
+    private fun zoomToNodes(map: MapboxMap) {
+        val nodes = nodesWithPosition()
+        if (nodes.isNotEmpty()) {
+            val update = if (nodes.size >= 2) {
+                // Multiple nodes, make them all fit on the map view
+                val bounds = LatLngBounds.Builder()
+
+                // Add all positions
+                bounds.includes(nodes.map { it.position!! }
+                    .map { LatLng(it.latitude, it.longitude) })
+
+                CameraUpdateFactory.newLatLngBounds(bounds.build(), 150)
+            } else {
+                // Only one node, just zoom in on it
+                val it = nodes[0].position!!
+
+                val cameraPos = CameraPosition.Builder().target(
+                    LatLng(it.latitude, it.longitude)
+                ).zoom(9.0).build()
+                CameraUpdateFactory.newCameraPosition(cameraPos)
+            }
+            map.animateCamera(update, 1000)
+        }
+    }
+
     override fun onCreateView(
         inflater: LayoutInflater, container: ViewGroup?,
         savedInstanceState: Bundle?
@@ -44,48 +119,9 @@ class MapFragment : ScreenFragment("Map"), Logging {
 
         mapView.getMapAsync { map ->
 
-            // Find all nodes with valid locations
-            val nodesWithPosition = NodeDB.nodes.values.filter { it.validPosition != null }
-            val locations = nodesWithPosition.map { node ->
-                val p = node.position!!
-                debug("Showing on map: $node")
-
-                val f = Feature.fromGeometry(
-                    Point.fromLngLat(
-                        p.longitude,
-                        p.latitude
-                    )
-                )
-                node.user?.let {
-                    f.addStringProperty("name", it.longName)
-                }
-                f
-            }
-            val nodeSourceId = "node-positions"
-            val nodeLayerId = "node-layer"
-            val labelLayerId = "label-layer"
-            val markerImageId = "my-marker-image"
-            val nodePositions =
-                GeoJsonSource(nodeSourceId, FeatureCollection.fromFeatures(locations))
-
             // val markerIcon = BitmapFactory.decodeResource(context.resources, R.drawable.ic_twotone_person_pin_24)
             val markerIcon = activity!!.getDrawable(R.drawable.ic_twotone_person_pin_24)!!
 
-            val nodeLayer = SymbolLayer(nodeLayerId, nodeSourceId).withProperties(
-                iconImage(markerImageId),
-                iconAnchor(Property.ICON_ANCHOR_BOTTOM),
-                iconAllowOverlap(true)
-            )
-
-            val labelLayer = SymbolLayer(labelLayerId, nodeSourceId).withProperties(
-                textField(Expression.get("name")),
-                textSize(12f),
-                textColor(Color.RED),
-                textVariableAnchor(arrayOf(TEXT_ANCHOR_TOP)),
-                textJustify(TEXT_JUSTIFY_AUTO),
-                textAllowOverlap(true)
-            )
-
             map.setStyle(Style.OUTDOORS) { style ->
                 style.addSource(nodePositions)
                 style.addImage(markerImageId, markerIcon)
@@ -95,28 +131,6 @@ class MapFragment : ScreenFragment("Map"), Logging {
 
             //map.uiSettings.isScrollGesturesEnabled = true
             //map.uiSettings.isZoomGesturesEnabled = true
-
-            if (nodesWithPosition.isNotEmpty()) {
-                val update = if (nodesWithPosition.size >= 2) {
-                    // Multiple nodes, make them all fit on the map view
-                    val bounds = LatLngBounds.Builder()
-
-                    // Add all positions
-                    bounds.includes(nodesWithPosition.map { it.position!! }
-                        .map { LatLng(it.latitude, it.longitude) })
-
-                    CameraUpdateFactory.newLatLngBounds(bounds.build(), 150)
-                } else {
-                    // Only one node, just zoom in on it
-                    val it = nodesWithPosition[0].position!!
-
-                    val cameraPos = CameraPosition.Builder().target(
-                        LatLng(it.latitude, it.longitude)
-                    ).zoom(9.0).build()
-                    CameraUpdateFactory.newCameraPosition(cameraPos)
-                }
-                map.animateCamera(update, 1000)
-            }
         }
     }
 
@@ -138,6 +152,11 @@ class MapFragment : ScreenFragment("Map"), Logging {
     override fun onResume() {
         super.onResume()
         mapView.onResume()
+
+        mapView.getMapAsync { map ->
+            nodePositions.setGeoJson(getCurrentNodes()) // Update node positions
+            zoomToNodes(map)
+        }
     }
 
     override fun onDestroy() {