How can I implement an extended app bar, like the one shown in the image?
To make a custom bar, the best option currently is to use a Toolbar and to do what that you want you can define the property android:minHeight
with the value ?attr/actionBarSize
to have as minimum height the one of the action bar:
android:minHeight="?android:attr/actionBarSize"
and define a fixed height by:
android:layout_height="128dp"
Example:
<android.support.v7.widget.Toolbar xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="128dp"
android:minHeight="?android:attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" />
I add an example of our friends from "beautiful programming": Toolbar on Android