ActionView set to an item in support NavigationView not showing

Question

I\'m using the support NavigationView in my navigation drawer to display menu of items.

Answer 1

I eventually found out what was causing the issue. For NavigationView to work properly with action views, you must use AppCompat support library version 23.1

So instead of

compile 'com.android.support:appcompat-v7:22.3.0'

I had to update to

compile 'com.android.support:appcompat-v7:23.1.1'

which made the trick and the action view in navigation drawer's navigation view started showing properly, exactly as I wanted.

---

When updating to the new AppCompat version I came across several more problems like ClassNotFoundException showing up when starting the app, which I fixed by updating all com.android.support libraries to the latest version:

compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.android.support:design:23.1.1'
compile 'com.android.support:recyclerview-v7:23.1.1'
compile 'com.android.support:support-annotations:23.1.1'
...

Then I was still getting NullPointerException in my header layout set to the NavigationView. If you're setting app:headerLayout="@layout/drawer_header" or similarly in code, in AppCompat version 22 it was possible to get the header view by findViewById().

AppCompat version 23, though, uses RecyclerView for all the items including the header view, so the way to get reference to its views is following:

 mHeaderView = navigationView.getHeaderView(HEADER_INDEX);

Where HEADER_INDEX is most likely 0 if you're not adding multiple headers.

Answer 2

I can change the text of the counter easily enough. However, The text view that I use is within a LinearLayout, and it has an android:id as well (I tried this without the LinearLayout without issue):

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/textCounter"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:gravity="center_vertical"
        android:textColor="@color/colorPrimary"
        android:text="5"/>
</LinearLayout>

Given that, I am able to see, access and modify the text view within the main activity using the following :

TextView countText = (TextView)findViewById(R.id.textCounter);

countText.setText("6");

Of course, I'm using a trivial method to calculate the value, just setting it to the value "6", but, I don't know what your counter structure actually looks like, and those are not the main concern of your question.

The issue with your ability to view the counter number remains a mystery. See my questions above and we'll hammer out that element as well.

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
}