Overflow button has disappeared

问题

A bit of an odd bug. I had set up my overflow button for navigation drawer application in the beginning before moving on to other parts. Somewhere along the way. At some point i must have changed a setting to cause it to disappear and im not sure what i did. My code below.

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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"
    android:fitsSystemWindows="true"
    tools:context="com.tble.brgo.BRGO">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:titleTextColor="@color/colorPrimaryDark"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>

<FrameLayout
    android:id="@+id/fragmentcontainer"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

</FrameLayout>

</android.support.design.widget.CoordinatorLayout>

And my overflow items

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/S14273"
        android:orderInCategory="100"
        android:title="High School"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14276"
        android:orderInCategory="100"
        android:title="Middle School"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14274"
        android:orderInCategory="100"
        android:title="Hillside"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14271"
        android:orderInCategory="100"
        android:title="Eisenhower"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14278"
        android:orderInCategory="100"
        android:title="Van Holten"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14277"
        android:orderInCategory="100"
        android:title="Milltown"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14275"
        android:orderInCategory="100"
        android:title="J.F.K. Primary"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14272"
        android:orderInCategory="100"
        android:title="Hamilton"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14269"
        android:orderInCategory="100"
        android:title="Crim Primary"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14268"
        android:orderInCategory="100"
        android:title="Bradely Gardens"
        app:showAsAction="never" />
    <item
        android:id="@+id/S14264"
        android:orderInCategory="100"
        android:title="Adamsville"
        app:showAsAction="never" />

</menu>

来源：https://stackoverflow.com/questions/39281317/overflow-button-has-disappeared