Refactor: unwrap map graph (#2111)

app/src/main/java/com/geeksville/mesh/navigation/MapRoutes.kt

@@ -20,7 +20,6 @@ package com.geeksville.mesh.navigation
 import androidx.navigation.NavGraphBuilder
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.composable
-import androidx.navigation.compose.navigation
 import com.geeksville.mesh.model.UIViewModel
 import com.geeksville.mesh.ui.map.MapView
 import kotlinx.serialization.Serializable
@@ -28,25 +27,18 @@ import kotlinx.serialization.Serializable
 sealed class MapRoutes {
     @Serializable
     data object Map : Route
-
-    @Serializable
-    data object MapGraph : Graph
 }
 
 fun NavGraphBuilder.mapGraph(
     navController: NavHostController,
     uiViewModel: UIViewModel,
 ) {
-    navigation<MapRoutes.MapGraph>(
-        startDestination = MapRoutes.Map,
-    ) {
-        composable<MapRoutes.Map> {
-            MapView(
-                model = uiViewModel,
-                navigateToNodeDetails = {
-                    navController.navigate(NodesRoutes.NodeDetail(it))
-                },
-            )
-        }
+    composable<MapRoutes.Map> {
+        MapView(
+            model = uiViewModel,
+            navigateToNodeDetails = {
+                navController.navigate(NodesRoutes.NodeDetail(it))
+            },
+        )
     }
 }

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

@@ -67,6 +67,7 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.navigation.NavDestination
 import androidx.navigation.NavDestination.Companion.hasRoute
 import androidx.navigation.NavDestination.Companion.hierarchy
+import androidx.navigation.NavGraph.Companion.findStartDestination
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.currentBackStackEntryAsState
 import androidx.navigation.compose.rememberNavController
@@ -195,19 +196,21 @@ fun MainScreen(
                         }
                     },
                     onClick = {
-                        navController.navigate(destination.route) {
-                            // Pop up to the start destination of the graph to
-                            // avoid building up a large stack of destinations
-                            // on the back stack as users select items
-//                            destination.route
-//                            popUpTo(navController.graph.findStartDestination().id) {
-//                                saveState = true
-//                            }
-                            // Avoid multiple copies of the same destination when
-                            // reselecting the same item
-                            launchSingleTop = true
-                            // Restore state when reselecting a previously selected item
-                            restoreState = true
+                        if (!isSelected) {
+                            navController.navigate(destination.route) {
+                                // Pop up to the start destination of the graph to
+                                // avoid building up a large stack of destinations
+                                // on the back stack as users select items
+                                destination.route
+                                popUpTo(navController.graph.findStartDestination().id) {
+                                    saveState = true
+                                }
+                                // Avoid multiple copies of the same destination when
+                                // reselecting the same item
+                                launchSingleTop = true
+                                // Restore state when reselecting a previously selected item
+                                restoreState = true
+                            }
                         }
                     }
                 )