I was implementing a searchview in the app bar in my app, so everything is nicely compact. Just checked my mails in GMail and noticed they don't seem to use the app bar. I googled a bit but couldn't find what they use. Is it a modified app bar design or a hovering searchview that got a modification for a menu? Any ideas?
Found the answer here: Android Google Search Bar with Drawer
For anyone that wants to test the code, I add even the required xml files (but you can use your own if you have): ic_menu.xml
<vector xmlns:android="http://schemas.android.com/apk/res/android" android:height="24dp"
android:viewportHeight="330" android:viewportWidth="330" android:width="24dp">
<path android:fillColor="#77000000"
android:pathData="M135,90H15c-8.284,0 -15,6.716 -15,15s6.716,15 15,15h120c8.284,0 15,-6.716 15,-15S143.284,90 135,90z"/>
<path android:fillColor="#77000000"
android:pathData="M135,150H15c-8.284,0 -15,6.716 -15,15c0,8.284 6.716,15 15,15h120c8.284,0 15,-6.716 15,-15C150,156.716 143.284,150 135,150z"/>
<path android:fillColor="#77000000"
android:pathData="M135,210H15c-8.284,0 -15,6.716 -15,15c0,8.284 6.716,15 15,15h120c8.284,0 15,-6.716 15,-15C150,216.716 143.284,210 135,210z"/>
</vector>
shape_round.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<corners android:radius="15dip" />
<solid android:color="@android:color/white" />
</shape>