Compose-Bottom-Navigation
Implementing bottom navigation in jetpack compose
Add the Navigation dependency
Open the app's build file, found at app/build.gradle.
In the dependencies section, add the navigation-compose
dependency.
dependencies {
implementation "androidx.navigation:navigation-compose:2.4.0-alpha04"
// other dependencies
}
You can create aNavController
by using the rememberNavController()
method in your composable:
val navController = rememberNavController()
Add screens
sealed class Screen (var route: String, @StringRes val resourceId: Int, var icon: ImageVector) {
object Home : Screen("home", R.string.home, Icons.Default.Home)
object Search : Screen("search",R.string.search, Icons.Default.Search )
object Settings : Screen("library", R.string.settings, Icons.Default.Settings)
object Profile : Screen("profile", R.string.profile, Icons.Default.Person)
}
Then place those items in a list that can be used by the BottomNavigationItem
val items = listOf(Screen.Home, Screen.Search, Screen.Settings, Screen.Profile)
)
Set bottom navigation at your composable function
val navController = rememberNavController()
Scaffold(
bottomBar = {
BottomNavigation {
val navBackStackEntry by navController.currentBackStackEntryAsState()
val currentDestination = navBackStackEntry?.destination
items.forEach { screen ->
BottomNavigationItem(
icon = { Icon(screen.icon, contentDescription = null) },
label = { Text(stringResource(screen.resourceId)) },
selected = currentDestination?.hierarchy?.any { it.route == screen.route } == true,
onClick = {
navController.navigate(screen.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
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
}
}
)
}
}
}
) { innerPadding ->
NavHost(navController, startDestination = Screen.Home.route, Modifier.padding(innerPadding)) {
composable(Screen.Home.route) { Home(navController) }
composable(Screen.Search.route) { Search(navController) }
composable(Screen.Settings.route) {Settings(navController) }
composable(Screen.Profile.route) { Profile(navController) }
}
}
}