title: Android: when / why should I use FrameLayout instead of Fragment?
body: <p>I am building a layout for large screens, that is supposed to consist of 2 different parts, a left one and a right one. For doing that I thought using 2 Fragments is the right choice. </p>
  
  <p>Then I had a look on the example of the navigation with the <strong>Master/Detail-Flow</strong>. It has a 2-pane layout, where on the right is the navigation, and on the left is the detail view.</p>
  
  <p>But in that example, different from what I expected to see, for the detail view there is a <code>FrameLayout</code> that then holds a <code>Fragment</code>, instead of a <code>Fragment</code> directly.</p>
  
  <p>The layout XML looks like this (an example):</p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_marginLeft="16dp"
      android:layout_marginRight="16dp"
      android:baselineAligned="false"
      android:divider="?android:attr/dividerHorizontal"
      android:orientation="horizontal"
      android:showDividers="middle"
      tools:context=".WorkStationListActivity" &gt;
  
      &lt;fragment
          android:id="@+id/workstation_list"
          android:name="de.tuhh.ipmt.ialp.history.WorkStationListFragment"
          android:layout_width="0dp"
          android:layout_height="match_parent"
          android:layout_weight="1"
          tools:layout="@android:layout/list_content" /&gt;
  
      &lt;FrameLayout
          android:id="@+id/workstation_detail_container"
          android:layout_width="0dp"
          android:layout_height="match_parent"
          android:layout_weight="3" /&gt;
  
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>My question now is: why is a <code>FrameLayout</code> used instead of the <code>Fragment</code> itself for the detail view? What is the reason or the advantage? Should I use it too?</p>