feat: add main nav host best practice

app/src/main/java/com/approagency/drug/MainActivity.kt

@@ -36,9 +36,7 @@ class MainActivity : ComponentActivity() {
         enableEdgeToEdge()
         setContent {
             DrugTheme {
-                val navController = rememberNavController()
-                val snackbarHostState = remember { SnackbarHostState() }
-                val scope = rememberCoroutineScope()
+
                 AppNavGraph(
 //                        navController = navController,
 //                        modifier = Modifier.padding(innerPadding)

app/src/main/java/com/approagency/drug/navigation/AppNavGraph.kt

@@ -1,9 +1,18 @@
 package com.approagency.drug.navigation
 
+import android.net.Uri
 import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.navigation.NavType
 import androidx.navigation.compose.NavHost
 import androidx.navigation.compose.composable
+import androidx.navigation.compose.navigation
 import androidx.navigation.compose.rememberNavController
+import androidx.navigation.navArgument
+import com.approagency.drug.presentation.screens.DrugDetailScreen
+import com.approagency.drug.presentation.screens.HomeScreen
+import com.approagency.drug.presentation.screens.LabScreen
+import com.approagency.drug.presentation.screens.SearchScreen
 
 @Composable
 fun AppNavGraph() {
@@ -12,12 +21,51 @@ fun AppNavGraph() {
 
     NavHost(
         navController = navController,
-        startDestination = "main_container"
+        startDestination = "home"
     ) {
 
-        composable("main_container") {
+        // ───────────────
+        // BOTTOM TABS
+        // ───────────────
 
-            MainContainer()
+        composable("home") {
+            MainContainer(navController) {
+                HomeScreen(navController , modifier = Modifier)
+            }
+        }
+
+        composable("search") {
+            MainContainer(navController) {
+                SearchScreen(navController)
+            }
+        }
+
+        composable("lab") {
+            MainContainer(navController) {
+                LabScreen()
+            }
+        }
+
+        // ───────────────
+        // GLOBAL SCREEN
+        // ───────────────
+
+        composable(
+            route = Screen.DrugDetail.route,
+            arguments = listOf(
+                navArgument("detailUrl") {
+                    type = NavType.StringType
+                }
+            )
+        ) {
+
+            val detailUrl =
+                Uri.decode(it.arguments?.getString("detailUrl") ?: "")
+
+            DrugDetailScreen(
+                navController = navController,
+                detailUrl = detailUrl
+            )
         }
     }
 }

app/src/main/java/com/approagency/drug/navigation/BottomBar.kt

@@ -39,62 +39,56 @@ import androidx.navigation.NavHostController
 import androidx.navigation.compose.currentBackStackEntryAsState
 
 @Composable
-fun BottomBar(
-    navController: NavHostController
-) {
+fun BottomBar(navController: NavHostController) {
+
     val items = listOf(
-        Triple(MainRoute.HomeGraph, "دارو", Icons.Default.Search),
-        Triple(MainRoute.SearchGraph, "سرچ", Icons.Rounded.Refresh),
-        Triple(MainRoute.LabGraph, "آزمایش", Icons.Default.Build)
+        Triple("home", "دارو", Icons.Default.Search),
+        Triple("search", "سرچ", Icons.Rounded.Refresh),
+        Triple("lab", "آزمایش", Icons.Default.Build)
     )
 
     val navBackStackEntry by navController.currentBackStackEntryAsState()
-    val currentDestination = navBackStackEntry?.destination
+    val currentRoute = navBackStackEntry?.destination?.route
+
     Surface(
         tonalElevation = 2.dp,
-        color = MaterialTheme.colorScheme.surface,
         modifier = Modifier
             .navigationBarsPadding()
-            .height(50.dp)
+            .height(56.dp)
     ) {
-        Row(
-            modifier = Modifier.fillMaxSize(),
-            verticalAlignment = Alignment.CenterVertically
-        ) {
+        Row(modifier = Modifier.fillMaxSize(),
+            verticalAlignment = Alignment.CenterVertically) {
 
             items.forEach { item ->
 
-                val selected = currentDestination
-                    ?.hierarchy
-                    ?.any { it.route == item.first.route } == true
+                val selected = currentRoute == item.first
 
                 val color = if (selected)
                     MaterialTheme.colorScheme.primary
                 else
                     MaterialTheme.colorScheme.onSurfaceVariant
-
                 val background = if (selected)
                     MaterialTheme.colorScheme.primary.copy(alpha = 0.12f)
                 else
                     Color.Transparent
-
                 Box(
                     modifier = Modifier
-                        .weight(1f)
-                        .padding(horizontal = 8.dp , vertical = 4.dp)
+                        .weight(1f).padding(horizontal = 8.dp , vertical = 4.dp)
                         .clip(MaterialTheme.shapes.large)
                         .background(background)
                         .clickable {
-                            navController.navigate(item.first.route) {
-                                popUpTo(navController.graph.findStartDestination().id) {
-                                    saveState = true
+                            if (!selected) {
+                                navController.navigate(item.first) {
+                                    popUpTo("home") {
+                                        saveState = true
+                                    }
+                                    launchSingleTop = true
+                                    restoreState = true
                                 }
-                                launchSingleTop = true
-                                restoreState = true
                             }
-                        }
-                        .padding(horizontal = 10.dp, vertical = 10.dp),
-                    contentAlignment = Alignment.Center
+                        }.padding(horizontal = 10.dp, vertical = 10.dp),
+
+                contentAlignment = Alignment.Center
                 ) {
 
                     Row(

app/src/main/java/com/approagency/drug/navigation/MainContainer.kt

@@ -1,51 +1,28 @@
 package com.approagency.drug.navigation
 
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.padding
 import androidx.compose.material3.Scaffold
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Modifier
+import androidx.navigation.NavHostController
 import androidx.navigation.compose.NavHost
 import androidx.navigation.compose.currentBackStackEntryAsState
-import androidx.navigation.compose.rememberNavController
-import com.approagency.drug.navigation.graphs.homeGraph
-import com.approagency.drug.navigation.graphs.labGraph
-import com.approagency.drug.navigation.graphs.searchGraph
-
 @Composable
-fun MainContainer() {
+fun MainContainer(
+    navController: NavHostController,
+    content: @Composable () -> Unit
+) {
 
-    val navController = rememberNavController()
-    val navBackStackEntry by navController.currentBackStackEntryAsState()
-
-    val currentRoute = navBackStackEntry?.destination?.route
-
-    val showBottomBar = when (currentRoute) {
-        Screen.Home.route,
-        Screen.Search.route,
-        Screen.Lab.route -> true
-        else -> false
-    }
     Scaffold(
         bottomBar = {
-            if (showBottomBar) {
                 BottomBar(navController)
-            }
         }
     ) { padding ->
 
-        NavHost(
-            navController = navController,
-            startDestination = MainRoute.HomeGraph.route,
-            modifier =if (showBottomBar ) Modifier.padding(padding) else Modifier
-
-        ) {
-
-            homeGraph(navController)
-
-            searchGraph(navController)
-
-            labGraph(navController)
+        Box(modifier = Modifier.padding(padding)) {
+            content()
         }
     }
 }

app/src/main/java/com/approagency/drug/navigation/graphs/HomeGraph.kt

@@ -1,28 +1,19 @@
-package com.approagency.drug.navigation.graphs
-
-import androidx.compose.ui.Modifier
-import androidx.navigation.NavGraphBuilder
-import androidx.navigation.NavHostController
-import androidx.navigation.compose.composable
-import androidx.navigation.navigation
-import com.approagency.drug.navigation.MainRoute
-import com.approagency.drug.navigation.Screen
-import com.approagency.drug.presentation.screens.HomeScreen
-
-fun NavGraphBuilder.homeGraph(
-    navController: NavHostController
-) {
-
-    navigation(
-        route = MainRoute.HomeGraph.route,
-        startDestination = Screen.Home.route
-    ) {
-
-        composable(Screen.Home.route) {
-
-            HomeScreen(
-                navController = navController , modifier = Modifier
-            )
-        }
-    }
-}
+//package com.approagency.drug.navigation.graphs
+//
+//import androidx.compose.ui.Modifier
+//import androidx.navigation.NavGraphBuilder
+//import androidx.navigation.NavHostController
+//import androidx.navigation.compose.composable
+//import androidx.navigation.navigation
+//import com.approagency.drug.navigation.MainRoute
+//import com.approagency.drug.navigation.Screen
+//import com.approagency.drug.presentation.screens.HomeScreen
+//
+//fun NavGraphBuilder.homeGraph(navController: NavHostController) {
+//
+//    composable(MainRoute.HomeGraph.route) {
+//        HomeScreen(
+//            navController = navController , modifier = Modifier
+//        )
+//    }
+//}

app/src/main/java/com/approagency/drug/navigation/graphs/LabGraph.kt

@@ -1,25 +1,16 @@
-package com.approagency.drug.navigation.graphs
-
-import androidx.navigation.NavGraphBuilder
-import androidx.navigation.NavHostController
-import androidx.navigation.compose.composable
-import androidx.navigation.navigation
-import com.approagency.drug.navigation.MainRoute
-import com.approagency.drug.navigation.Screen
-import com.approagency.drug.presentation.screens.LabScreen
-
-fun NavGraphBuilder.labGraph(
-    navController: NavHostController
-) {
-
-    navigation(
-        route = MainRoute.LabGraph.route,
-        startDestination = Screen.Lab.route
-    ) {
-
-        composable(Screen.Lab.route) {
-
-            LabScreen()
-        }
-    }
-}
+//package com.approagency.drug.navigation.graphs
+//
+//import androidx.navigation.NavGraphBuilder
+//import androidx.navigation.NavHostController
+//import androidx.navigation.compose.composable
+//import androidx.navigation.navigation
+//import com.approagency.drug.navigation.MainRoute
+//import com.approagency.drug.navigation.Screen
+//import com.approagency.drug.presentation.screens.LabScreen
+//
+//fun NavGraphBuilder.labGraph(navController: NavHostController) {
+//
+//    composable(MainRoute.LabGraph.route) {
+//        LabScreen()
+//    }
+//}

app/src/main/java/com/approagency/drug/navigation/graphs/SearchGraph.kt

@@ -1,51 +1,20 @@
-package com.approagency.drug.navigation.graphs
-
-import android.net.Uri
-import androidx.navigation.NavGraphBuilder
-import androidx.navigation.NavHostController
-import androidx.navigation.NavType
-import androidx.navigation.compose.composable
-import androidx.navigation.navArgument
-import androidx.navigation.navigation
-import com.approagency.drug.navigation.MainRoute
-import com.approagency.drug.navigation.Screen
-import com.approagency.drug.presentation.screens.DrugDetailScreen
-import com.approagency.drug.presentation.screens.SearchScreen
-
-fun NavGraphBuilder.searchGraph(
-    navController: NavHostController
-) {
-
-    navigation(
-        route = MainRoute.SearchGraph.route,
-        startDestination = Screen.Search.route
-    ) {
-
-        composable(Screen.Search.route) {
-
-            SearchScreen(
-                navController = navController
-            )
-        }
-
-        composable(
-            route = Screen.DrugDetail.route,
-            arguments = listOf(
-                navArgument("detailUrl") {
-                    type = NavType.StringType
-                }
-            )
-        ) {
-
-            val detailUrl =
-                Uri.decode(
-                    it.arguments?.getString("detailUrl") ?: ""
-                )
-
-            DrugDetailScreen(
-                navController = navController,
-                detailUrl = detailUrl
-            )
-        }
-    }
-}
+//package com.approagency.drug.navigation.graphs
+//
+//import android.net.Uri
+//import androidx.navigation.NavGraphBuilder
+//import androidx.navigation.NavHostController
+//import androidx.navigation.NavType
+//import androidx.navigation.compose.composable
+//import androidx.navigation.navArgument
+//import androidx.navigation.navigation
+//import com.approagency.drug.navigation.MainRoute
+//import com.approagency.drug.navigation.Screen
+//import com.approagency.drug.presentation.screens.DrugDetailScreen
+//import com.approagency.drug.presentation.screens.SearchScreen
+//
+//fun NavGraphBuilder.searchGraph(navController: NavHostController) {
+//
+//    composable(MainRoute.SearchGraph.route) {
+//        SearchScreen(navController)
+//    }
+//}