MenuItemCompat.getActionView always returns null

In my case it was ProGuard file. You need to add this line:

-keep class android.support.v7.widget.SearchView { *; }

For me, an incorrect menu.xml namespace import caused this problem.

My original menu.xml:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/tools">
        <item android:id="@+id/action_search"
              android:title="@string/map_option_search"
              android:icon="@drawable/ic_action_search"
              app:showAsAction="collapseActionView|ifRoom"
              app:actionViewClass="android.support.v7.widget.SearchView"/>
</menu>

It looks like the xmlns:app="http://schemas.android.com/tools" was causing MenuItemCompat.getActionView() to return null. Changing this import to xmlns:app="http://schemas.android.com/apk/res-auto" fixed the problem.

New working menu.xml:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto">
       <item android:id="@+id/action_search"
              android:title="@string/map_option_search"
              android:icon="@drawable/ic_action_search"
              app:showAsAction="collapseActionView|ifRoom"
              app:actionViewClass="android.support.v7.widget.SearchView"/>
</menu>

Finally I found the solution.

1. Changing namespace of actionViewClass from android:actionViewClass to app:actionViewClass

2. Implementing android.support.v7.widget.SearchView.OnQueryTextListener interface for current activity.

3. Directly use setOnQueryTextListener instead of SearchViewCompat.setOnQueryTextListener

   @Override
   public boolean onCreateOptionsMenu(Menu menu) {
     MenuInflater inflater = getMenuInflater();
     inflater.inflate(R.menu.menu, menu);
   
     MenuItem searchItem = menu.findItem(R.id.action_search);
     SearchView searchView = (SearchView) MenuItemCompat.getActionView(searchItem);
     if (searchView != null) {
        searchView.setOnQueryTextListener(this);
     }
   
     return super.onCreateOptionsMenu(menu);
   }
   

I think that the problem is that you use the SearchView from the Support V7 package and maybe your API level is set to.....22??.

Changing your code to the following in order to fix the problem:

menu.xml

<?xml version="1.0" encoding="UTF-8" ?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
    <item 
        android:id="@+id/action_search"
        android:icon="@drawable/actionbar_button_search"
        android:title="Search"
        android:showAsAction="always"
        android:actionViewClass="android.widget.SearchView" />
</menu>