This Example will demonstrate how to use NavigationView in Android with kotlin. NavigationView is a better approach to navigate different screens in Android application. This is an alternate to NavigationDrawer in android. Generally in Android NavigationView resides inside DrawerLayout.
Let's implement how to use navigationview in android
Step 1: Create a new project in Android Studio, go to File ⇒ New Project and enter all required details
Step 2: Add below code inside activity_main.xml file
<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<include
layout="@layout/app_bar_main"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<com.google.android.material.navigation.NavigationView
android:id="@+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true"
app:headerLayout="@layout/nav_header_main"
app:menu="@menu/activity_main_drawer" />
</androidx.drawerlayout.widget.DrawerLayout>
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In the above layout file we added NavigationView inside DrawerLayout
This NavigationView will attributes like app:headerLayout, app:menu attributes
app:headerLayout attributes will use for add the Header of the Side Navigationbar, like we can add any profile pic, name, email address fields.
app:menu will be used to add Navigation Menu items. in this example we added below navigationMenu items in menu folder
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
tools:showIn="navigation_view">
<group android:checkableBehavior="single">
<item
android:id="@+id/nav_home"
android:icon="@drawable/ic_menu_camera"
android:title="@string/menu_home" />
<item
android:id="@+id/nav_gallery"
android:icon="@drawable/ic_menu_gallery"
android:title="@string/menu_gallery" />
<item
android:id="@+id/nav_slideshow"
android:icon="@drawable/ic_menu_slideshow"
android:title="@string/menu_slideshow" />
</group>
</menu>
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To display the Current selected NavigationView item we have used NavHostFragment which will handle the Navigation between screens.
This NavHostFragment is new Navigation Component under Jetpack component. To set the Navigation Items we will use app:navGraph the attribute.
<fragment
android:id="@+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="@navigation/mobile_navigation" />
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Step 3: Now update MainActivity.kt code like below
package com.android.videos.navigationview
import android.graphics.Color
import android.os.Bundle
import android.view.Menu
import com.google.android.material.floatingactionbutton.FloatingActionButton
import com.google.android.material.snackbar.Snackbar
import com.google.android.material.navigation.NavigationView
import androidx.navigation.findNavController
import androidx.navigation.ui.AppBarConfiguration
import androidx.navigation.ui.navigateUp
import androidx.navigation.ui.setupActionBarWithNavController
import androidx.navigation.ui.setupWithNavController
import androidx.drawerlayout.widget.DrawerLayout
import androidx.appcompat.app.AppCompatActivity
import androidx.appcompat.widget.Toolbar
class MainActivity : AppCompatActivity() {
private lateinit var appBarConfiguration: AppBarConfiguration
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_navigation_view)
val toolbar: Toolbar = findViewById(R.id.toolbar)
setSupportActionBar(toolbar)
val fab: FloatingActionButton = findViewById(R.id.fab)
fab.setOnClickListener { view ->
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show()
}
fab.setColorFilter(Color.WHITE)
val drawerLayout: DrawerLayout = findViewById(R.id.drawer_layout)
val navView: NavigationView = findViewById(R.id.nav_view)
val navController = findNavController(R.id.nav_host_fragment)
// Passing each menu ID as a set of Ids because each
// menu should be considered as top level destinations.
appBarConfiguration = AppBarConfiguration(
setOf(
R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow
), drawerLayout
)
setupActionBarWithNavController(navController, appBarConfiguration)
navView.setupWithNavController(navController)
}
override fun onCreateOptionsMenu(menu: Menu): Boolean {
// Inflate the menu; this adds items to the action bar if it is present.
menuInflater.inflate(R.menu.navigation_view, menu)
return true
}
override fun onSupportNavigateUp(): Boolean {
val navController = findNavController(R.id.nav_host_fragment)
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
}
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Step 4: Now create a Menu Item Screens. Here we have Home, Gallery, SlideShow screens.
Let's create a resource file for Home Screen
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.home.HomeFragment">
<TextView
android:id="@+id/text_home"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:textAlignment="center"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
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To handle the Data we are using ViewModel, so let's create a viewmodel with HomeViewModel class
import androidx.lifecycle.LiveData
import androidx.lifecycle.MutableLiveData
import androidx.lifecycle.ViewModel
class HomeViewModel : ViewModel() {
private val _text = MutableLiveData<String>().apply {
value = "This is home Fragment"
}
val text: LiveData<String> = _text
}
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Read Android ViewModel Interview questions
Now we need to create Viewmodel instance
ViewModelProvider(this).get(HomeViewModel::class.java)
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HomeFragment code will be like this
package com.android.videos.navigationview.ui.home
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.fragment.app.Fragment
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProvider
import com.android.videos.navigationview.R
class HomeFragment : Fragment() {
private lateinit var homeViewModel: HomeViewModel
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
homeViewModel =
ViewModelProvider(this).get(HomeViewModel::class.java)
val root = inflater.inflate(R.layout.fragment_home, container, false)
val textView: TextView = root.findViewById(R.id.text_home)
homeViewModel.text.observe(viewLifecycleOwner, Observer {
textView.text = it
})
return root
}
}
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Similarly create Remaining Menu Screens and add it to the NavigationView
Step 5: Run application
Check you have connected Android Mobile device with your computer or run with Android emulator. To run the application in android studio, select your current module on Edit run/debug configuration and select your required device from the devices list which you are connected then click Run icon .
Related Topics
How do i use Bottom Navigationview in android with Kotlin
Android ViewModel Interview questions
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