An Abstract Activity for Hosting a Fragment
In a moment, you will create the CrimeListActivity class that will host a CrimeListFragment. First, you are going to set up a view for CrimeListActivity.
A generic fragment-hosting layout
For CrimeListActivity, you can simply reuse the layout defined in activity_crime.xml (which is copied in Listing 8.4). This layout provides a FrameLayout as a container view for a fragment, which is then named in the activity’s code.
activity_crime.xml is already generic
<?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/fragment_container" android:layout_width="match_parent" android:layout_height="match_parent" ...