How to enable navigation drawer only when we are in a certain fragment?-CodePudding

I want to set my navigation drawer menu on a Fragment. I don't want the navigation drawer to show up when I start my app. I want it to show up after I enter another page (i.e. not first page). But the problem is, onSupportNavigateUp can only be written on MainActivity, which is the first page.

This is my MainActivity.kt :

class MainActivity : AppCompatActivity() {
    private lateinit var drawerLayout: DrawerLayout
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        @Suppress("UNUSED_VARIABLE")

        val binding = DataBindingUtil.setContentView<ActivityMainBinding>(this, R.layout.activity_main)
        drawerLayout = binding.drawerLayout

        val navController = this.findNavController(R.id.myNavHostFragment)
        NavigationUI.setupActionBarWithNavController(this,navController, drawerLayout)
        NavigationUI.setupWithNavController(binding.navView, navController)
    }

    override fun onSupportNavigateUp(): Boolean {
        val navController = this.findNavController(R.id.myNavHostFragment)
        return NavigationUI.navigateUp(navController, drawerLayout)
    }
}

Here is my activity_main.xml `

<androidx.drawerlayout.widget.DrawerLayout
    android:id="@ id/drawerLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <fragment
            android:id="@ id/myNavHostFragment"
            android:name="androidx.navigation.fragment.NavHostFragment"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:navGraph="@navigation/navigation"
            app:defaultNavHost="true"
            />
    </LinearLayout>
    <com.google.android.material.navigation.NavigationView
        android:id="@ id/navView"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        app:headerLayout="@layout/nav_header"
        app:menu="@menu/navdrawer_menu" />
</androidx.drawerlayout.widget.DrawerLayout>

It takes fragment_title.xml display and use it for activity_main.xml display by using fragment tag and NavHostFragment.

I also have another fragment called fragment_home.xml and HomeFragment.kt class.

What I don't know is, how to not show the navigation drawer when I'm on title fragment and start showing the navigation drawer when I'm on home fragment?

CodePudding user response：

Below code will set navView visibility gone in TitleFragment and set visible on the other destinations:

        navController.addOnDestinationChangedListener { _, destination, _ ->
            if (destination.id == R.id.titleFragment) {
                navView.visibility = View.GONE
            } else {
                navView.visibility = View.VISIBLE
            }
        }