title: SharedPreferences.getBoolean returns true everytime
body: <p>I made a class for handling important data changes such as App Purchase Status and other stuff .</p>
  
  <p>For this goal I have created a class which does the setting and reading of the values. but the problem is whenever I call the appIsPurchased() method, the result is true while it hasen't been changed since app installation and its first initial launch.</p>
  
  <p>This is my code:</p>
  
  <pre><code>/**
   * Created by neemasa on 5/29/14.
   * This class handles more crucial data values within app.
   */
  public class AppCore {
  
      private SharedPreferences settings;
      private String keyPurchase = "app_purchased";
      private Context context;
  
      public AppCore(Context context){
          this.context = context;
          settings = PreferenceManager.getDefaultSharedPreferences(context);
      }
  
      public void setAppInPurchasedMode(String status){
          if (status.equals("successful")){
              settings.edit().putBoolean(keyPurchase, true).commit();
          }else if (status.equals("failed")){
              settings.edit().putBoolean(keyPurchase, false).commit();
          }
  
      }
      public boolean appIsPurchased(){
          boolean purchased = false;
          if (settings.getBoolean(keyPurchase,true)){
              purchased = true;
          }
          return purchased;
      }
  
  }
  </code></pre>
  
  <p><hr />
  Question 1st: is there something wrong with my code? if there is then why appIsPurchased() always return true? <br />
  Question 2nd: do all values in the shared preferences are true by default? <br /></p>
  
  <hr />
  
  <p>Meanwhile when I use this class in my code the toast "Purchased!" runs even when app is running for the first time.</p>
  
  <pre><code>@Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
          AppCore appCore = new AppCore(getApplicationContext());
          if (appCore.appIsPurchased()){
              Toast.makeText(getApplicationContext(),"Purchased!",Toast.LENGTH_SHORT).show();
          }else {
              Toast.makeText(getApplicationContext(),"Not Purchased!",Toast.LENGTH_SHORT).show();
          }
  }
  </code></pre>