Question

I have a SettingsActivity which is a subclass of PreferenceActivity in my library project

The oncreate method looks like this

addPreferencesFromResource(R.xml.preferences);
setContentView(R.layout.main);

The preference.xml file has structure like element PreferenceScreen -> PreferenceCategory -> Preference
My main main.xml Looks like this

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          android:layout_width="fill_parent"
          android:layout_height="fill_parent"
          android:orientation="vertical">


  <!--Listview will be replaced by preferences  -->

  <ListView android:id="@android:id/list"
          android:layout_width="fill_parent"
          android:layout_height="fill_parent" />

</LinearLayout>

The above class SettingsActivity is subclassed in another project and Looks like this

public class SettingsActivityFree extends SettingsActivity 
{
       private AdView adView;

       @Override
   protected void onCreate(Bundle savedInstanceState) 
       {        
    super.onCreate(savedInstanceState);

            //...

            // layout returned will be null ..
            LinearLayout layout = (LinearLayout)findViewById(R.layout.main);

            // Add the adView to it
            layout.addView(adView);
       }

The problem is I am trying to get LinearLayout from the parent class so that I can add my stuff in it, but for some reason it returns null , the reason I have LinearLyout in the SettingsActivity class is because I want to put some ads etc at the top of preferences and without putting ad specific code in the Library project

Please advise If I am missing something here,

Thanks

Answer 1

First you need to give your LinearLayout an id using android:id="@+id/whatever". Then you can search for it using findViewById(R.id.whatever).