Creating a Preference Activity in Android

In this tutorial we will build a preference screen using the PreferenceActivity class. Our main activity will contain 2 Buttons and a TextView. One of the buttons will open the preference screen, and the other will display the values stored in SharedPreferences.

The final output should look like this:

 

And here’s what happens when clicking on the Username/Password fields (left screenshot), and the List Preference field (right screenshot):

 

At a first glance it may look a bit intimidating, but as you will see later, actually it’s quite easy to define a preference screen. Trust me, I’m an engineer! (c):)

To put all this things together in a fashionable way, we will be using the PreferenceActivity class. The good thing about this class is that the definition of layout file it’s very simple. It provides custom controls specially designed for preference screens. Another good thing is that you don’t need to write code to save the values from preference screen to SharedPreferences. All this work is done automatically by the activity.

 

So, lets begin creating our preference screen

1. Create a new project in Eclipse:
Project: PreferenceDemoTest
Activity: PreferenceDemoActivity

2. Create a new Android XML file prefs.xml in the folder res/xml/. This file will contain the layout for our preference screen:

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >
 <PreferenceCategory
   android:summary="Username and password information"
   android:title="Login information" >
  <EditTextPreference
     android:key="username"
     android:summary="Please enter your login username"
     android:title="Username" />
  <EditTextPreference
     android:key="password"
     android:summary="Enter your password"
     android:title="Password" />
 </PreferenceCategory>

 <PreferenceCategory
   android:summary="Username and password information"
   android:title="Settings" >
  <CheckBoxPreference
     android:key="checkBox"
     android:summary="On/Off"
     android:title="Keep me logged in" />

  <ListPreference
     android:entries="@array/listOptions"
     android:entryValues="@array/listValues"
     android:key="listpref"
     android:summary="List preference example"
     android:title="List preference" />
 </PreferenceCategory>
</PreferenceScreen>

Notice that the root element of prefs.xml is the <PreferenceScreen> element, and not a RelativeLayout or LinearLayout for example. When a PreferenceActivity points to this layout file, the <PreferenceScreen> is used as the root, and the contained preferences are shown.

<PreferenceCategory> – defines a preference category. In our example the preference screen is split in two categories: “Login Information” and “Settings”

<EditTextPreference> – defines a text field for storing text information.

<CheckBoxPreference> – defines a checkbox.

<ListPreference> – defines a list of elements. The list appears as group of radio buttons.

 

3. At this stage the prefs.xml might complain that the @array/listOptions and @array/listValues resources cannot be found.

To fix this create a new XML file array.xml in the folder res/values/. This file will contain the elements of the ListPreference.

<?xml version="1.0" encoding="utf-8"?>
 <resources>
   <string-array name="listOptions">
     <item>Option 1</item>
     <item>Option 2</item>
     <item>Option 3</item>
     </string-array>

   <string-array name="listValues">
     <item>1 is selected</item>
     <item>2 is selected</item>
     <item>3 is selected</item>
   </string-array>
 </resources>

The “listOptions” array defines the elements of the list, or with other words, the labels.

The “listValues” array defines the values of each element. These are the values that will be stored in the SharedPreferences. The number of list options and list values should match. The first list value is assinged to the first list option, the second value to the second option,… and so on.

 

4. Create a new class PrefsActivity.java that extends PreferenceActivity:


public class PrefsActivity extends PreferenceActivity{

@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   addPreferencesFromResource(R.xml.prefs);
}
}

Notice that instead of the traditional setContentView(), we use here addPreferencesFromResource() method. This inflates our prefs.xml file and uses it as the Activity’s current layout.

 

5. Add the PrefsActivity.java to the AndroidManifest file:

<application
......./>
  <activity
    android:name=".PrefsActivity"
    android:theme="@android:style/Theme.Black.NoTitleBar" >
  </activity>
</application>

 

6. Now, to test our preference activity lets modify the main.xml layout file by adding 2 Buttons and 1 TextView. One of the buttons will open the preference screen, and the other will display the values stored in SharedPreferences.

main.xml:

<?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" >

<Button
  android:id="@+id/btnPrefs"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="Preferences Screen" />

<Button
  android:id="@+id/btnGetPreferences"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="Display Shared Preferences" />

<TextView
  android:id="@+id/txtPrefs"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content" />

</LinearLayout>

 

7. Finally, modify the PreferenceDemoActivity to handle our logic implementation:

public class PreferenceDemoActivity extends Activity {
TextView textView;

@Override
public void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.main);

   Button btnPrefs = (Button) findViewById(R.id.btnPrefs);
   Button btnGetPrefs = (Button) findViewById(R.id.btnGetPreferences);

   textView = (TextView) findViewById(R.id.txtPrefs);

   View.OnClickListener listener = new View.OnClickListener() {

   @Override
   public void onClick(View v) {
   switch (v.getId()) {
   case R.id.btnPrefs:
      Intent intent = new Intent(PreferenceDemoActivity.this,
      PrefsActivity.class);
      startActivity(intent);
      break;

   case R.id.btnGetPreferences:
      displaySharedPreferences();
      break;

   default:
     break;
   }
   }
   };

   btnPrefs.setOnClickListener(listener);
   btnGetPrefs.setOnClickListener(listener);
}

private void displaySharedPreferences() {
   SharedPreferences prefs = PreferenceManager
    .getDefaultSharedPreferences(PreferenceDemoActivity.this);

   String username = prefs.getString("username", "Default NickName");
   String passw = prefs.getString("password", "Default Password");
   boolean checkBox = prefs.getBoolean("checkBox", false);
   String listPrefs = prefs.getString("listpref", "Default list prefs");

   StringBuilder builder = new StringBuilder();
   builder.append("Username: " + username + "\n");
   builder.append("Password: " + passw + "\n");
   builder.append("Keep me logged in: " + String.valueOf(checkBox) + "\n");
   builder.append("List preference: " + listPrefs);

   textView.setText(builder.toString());
}
}

Here we attach 2 listeners for each button and display the values retrieved from  SharedPreferences in a TextView.

By this time you should compile and run successfully the application.

35 thoughts on “Creating a Preference Activity in Android

  1. Nice tutorial on using preferences. I’ve used them before but not with checkboxes and lists. Thank you very much.

    One question… I’m not understanding the View class the way it’s used here:

    View.OnClickListener listener = new View.OnClickListener() {

    You’re setting a static listener, but I’ve never seen this done before. Is View always a default reference to the current view or something? Are you setting a click listener for the entire activity? I’m pretty new so thanks for your help, and for this nice tutorial.

    1. Hi,
      Thank you for your appreciation.

      Well, actually it’s not about the View class itself here…

      Let me try clear up the things.
      The main activity has 2 Buttons, each with its own specific purpose.
      There are 2 ways you can make these buttons react to click events:
      1. your main activity class implements the OnClickListener interface and you provide the implementation for the onClick() method:
      public class PreferenceDemoActivity extends Activity implements OnClickListener{
      @Override
      public void onClick(View v) {

      or

      2. define an anonymous inner class and provide the implementation for the onClick() method (like in tutorial):
      OnClickListener listener = new OnClickListener() {
      @Override
      public void onClick(View v) {

      and just after the definition of anonymous inner class, attach the click listener to buttons:
      btnPrefs.setOnClickListener(listener);
      btnGetPrefs.setOnClickListener(listener);

      And the answer to what does View do, is that the “OnClickListener” interface is part of “android.view.View;” package and to access this interface I’m using the package_name.interface_name: View.OnClickListener

      If this is confusing for you, you could write:
      OnClickListener listener = new OnClickListener() {, but in this case make sure you add this statement to your import section:
      import android.view.View.OnClickListener;

  2. how to embed expandabe list in Preference screen. I mean PreferenceCategory as parent list and preferences within preferenceCategory as children within, like expandable list view

  3. i run the code.
    But when i click on option in list .the application gives.is there any code require when user selects an option in preference.how will it be stored in the preferences.

    1. @Kami, nope! I just implemented a Preference Activity in my program. You’re not missing anything, since your code “extends PreferenceActivity”, that “PreferenceActivity” code actually takes care of saving your preferences for you! I just unchecked a preference, and the value changed from “true” to “false” all on it’s own, even after a reboot.

      From what I’ve read, technically it makes a small sqlite database to store preferences, named after your app — so mine is com.fropco.UltraWifiManager, so the preferences are stored in com.fropco.UltraWifiManager_preferences. But getDefaultSharedPreferences takes care of the filename anyway.

  4. Awesome tutorial – thank you. I learned from this and even implemented a button within the preferences page. Good stuff!

  5. Nice tutorial

    I tried to run this under Eclipse, and it seems that ‘addPreferencesFromResource ‘ is deprecated. I have API level 17.

    What’s the alternative to addPreferencesFromResource ?

  6. i m doing same thing but i want to sort my list so can anyone tell me how can i handle the radio button checked event??

  7. addPreferencesFromResource() is deprecated in API 11. What are some other options available for doing the same.d

  8. hi,
    I create 10 new activities of my friends name with phone numbers . I just want to call from there with a button click and return back after call ended to d activity, not to d main activity. plz guide. I almost make d project but after ending the phone call it returns to d main activity.

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