How to add overflow menu to Toolbar?

Question

I'm trying to use Android ActionBar in my app, and have an option that's hidden away in the overflow menu.

There's a lot of documentation out there, but it's confusing because most of it is only relevant to very old versions of Android, and when you try applying the same concepts, they don't work anymore or work differently.

This is in my Activity layout

<android.support.v7.widget.Toolbar
    android:id="@+id/my_toolbar"
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:titleTextColor="@android:color/white"
    android:background="@color/colorPrimary"
    android:elevation="4dp"
    android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>

And this is in my Activity's onCreate() method

// sets up activity toolbar
Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(myToolbar);

myToolbar.showOverflowMenu();
myToolbar.setTitleTextColor(R.color.lightPrimaryText);

I've also tried inflating a menu xml file from the onCreateOptionsMenu(), but that also didn't give me the results I wanted.

Answer 1

Define a Menu for your Toolbar in the res/menu resource folder, for example:

toolbar_menu.xml

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context=".activity.MainActivity">

    <item
        android:id="@+id/action_sign_out"
        android:title="@string/toolbar_sign_out"
        app:showAsAction="never"/>
</menu>

Setting app:showAsAction="never" ensures that this MenuItem will not be shown in the Toolbar, but placed in the overflow menu instead.

The theme of your Activity should be (or derive from) one of the NoActionBar themes (Theme.AppCompat.NoActionBar for example, or Theme.MaterialComponents.NoActionBar if you're using Material Components).

In your Activity, set up your Toolbar:

Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(myToolbar);

And override onCreateOptionsMenu() to inflate your previously defined menu resource:

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.toolbar_menu, menu);
    return true;
}

You can override onOptionsItemSelected() to define the onClick behaviour of your MenuItem(s):

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_sign_out: {
            // do your sign-out stuff
            break;
        }
        // case blocks for other MenuItems (if any)
    }
    return true;
}