How add a spinner the navigation drawer in the fragment

Question

I want to add a spinning top to the navigation drawer.I want it to look like this:

I couldn't find how and where to add.I always get this error when I try to find id

my spinner layout

<Spinner
    xmlns:android="http://schemas.android.com/apk/res/android"

            android:id="@+id/qualitySpinner"
            android:layout_marginLeft="50dp"
            android:entries="@array/mQuality"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>

and my items

<item
        android:id="@+id/right_menu_spinner"
        android:icon="@drawable/icon_default"
        android:title="Quality"
        app:actionLayout="@layout/spinner_layout"/>

and my fragment code

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        val array = arrayOf("deneme","deneme")
        val denemeSp : Spinner = view.findViewById(R.id.qualitySpinner)
        denemeSp.adapter = ArrayAdapter(view.context,android.R.layout.simple_spinner_item,array)
        denemeSp.setOnItemSelectedListener(this)
}

but when it works it gives the following error:

2020-06-07 23:12:41.292 6872-6872/com.enesseval.moviedeneme E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.enesseval.moviedeneme, PID: 6872
    java.lang.IllegalStateException: view.findViewById(R.id.qualitySpinner) must not be null
        at com.enesseval.moviedeneme.view.MoviesFragment.onViewCreated(MoviesFragment.kt:57)
        at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:332)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1187)
        at androidx.fragment.app.FragmentManager.addAddedFragments(FragmentManager.java:2224)
        at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1997)
        at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1953)
        at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1849)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2629)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
        at androidx.fragment.app.Fragment.performActivityCreated(Fragment.java:2722)
        at androidx.fragment.app.FragmentStateManager.activityCreated(FragmentStateManager.java:346)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1188)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1356)
        at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1434)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1497)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2625)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:201)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1425)
        at android.app.Activity.performStart(Activity.java:7825)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3294)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:221)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:201)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:173)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
2020-06-07 23:12:41.308 6872-6872/com.enesseval.moviedeneme I/Process: Sending signal. PID: 6872 SIG: 9

Answer 1

Your menu item should be something like (I edited the stock android studio Navigation project template for illustative purposes) :

<item
    android:id="@+id/right_menu_spinner"
    android:icon="@drawable/icon_default"
    android:title="Quality"
    app:actionViewClass="androidx.appcompat.widget.AppCompatSpinner"/>

And access in your Activity, not fragment :

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Setup code ...


        // Access Navigation header and menu
        val navView: NavigationView = findViewById(R.id.nav_view)
        (navView.menu.findItem(R.id.right_menu_spinner).actionView as Spinner).run {
            adapter = ArrayAdapter(this@MainActivity, android.R.layout.simple_list_item_1, arrayOf("High", "Medium", "Low"))
        }
    }

}

Result :