title: frangment landscape how replace correctly
body: <p>i have an app with many fragments. this is layout on horizontal mode:</p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="horizontal"
      android:layout_width="match_parent"
      android:layout_height="match_parent"&gt;
  
      &lt;fragment android:name="com.map.manager.ListUser"
            android:id="@+id/listuser_fragment"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="match_parent" /&gt;
  
      &lt;fragment android:name="com.map.manager.DetailApp"
            android:id="@+id/detailapp_fragment"
            android:layout_weight="2"
            android:layout_width="0dp"
            android:layout_height="match_parent" /&gt;   
  
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>i can see my fragments correcty but if i do this:</p>
  
  <pre><code>            DetailUser appFrag = (DetailUser)
                      getSupportFragmentManager().findFragmentById(R.id.detailuser_fragment);
  
              if (appFrag != null) {
                  // If article frag is available, we're in two-pane layout...
  
                  // Call a method in the ArticleFragment to update its content
                  appFrag.updateAppointmentView(position);
  
              } 
              else {
              DetailUser dtuser = new DetailUser();
              FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
              transaction.replace(R.id.detailapp_fragment, dtuser);
              transaction.commit();
  </code></pre>
  
  <p>i can replace fragments but i can see old fragment into backgroud..
  i read <a href="https://stackoverflow.com/questions/5907673/android-cant-replace-one-fragment-with-another">THIS</a> i can't replace static fragments but how add it dynamically? (more than one into horizontal mode..) Can i replace a fragment without knowing old fragment?    </p>