title: notificationID cannot be resolved to a variable
body: <p>I have just started studying Android, I have limited java knowledge but am semi capable with c/c++ objective C etc... I am currently working through a p2pwrox ebook called Beginning Android Application Development that I brought, however I am coming unstuck with the "Try it out: Display Notifications on the status bar" on pg73.</p>
  
  <p>I have managed to write it all out sweet and am getting used to the android sdk and eclipse ide, however I have got this error in my NotificationActivity.java file shown below that I just don't know how to fix.</p>
  
  <pre><code>    package com.androidtestingfun.www;
  
  import android.app.Activity;
  import android.os.Bundle;
  import android.app.Notification;
  import android.app.NotificationManager;
  import android.app.PendingIntent;
  import android.content.Intent;
  import android.view.View;
  import android.widget.Button;
  
  public class NotificationsActivity extends Activity {
      /** Called when the activity is first created. */
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.main);
  
          Button button = (Button) findViewById(R.id.btn_displaynotif);
          button.setOnClickListener(new Button.OnClickListener() {
              public void onClick(View v) {
                  displayNotification();
              }
          });
      }
  
      protected void displayNotification()
      {
          //---PendingIntent to launch activity if the user selects this notification---
          Intent i = new Intent(this, NotificationView.class);
          i.putExtra("notificationID", notificationID); //-----the second parameter here is getting an error
  
          PendingIntent pendingIntent = 
                  PendingIntent.getActivity(this, 0, i, 0);
  
          NotificationManager nm = (NotificationManager)
                  getSystemService(NOTIFICATION_SERVICE);
  
          Notification notif = new Notification(
                  R.drawable.icon,
                  "Reminder: Meeting starts in 5 minutes",
                  System.currentTimeMillis());
  
          CharSequence from = "System Alarm";
          CharSequence message = "Meeting with customer at 3pm...";
  
          notif.setLatestEventInfo(this, from, message, pendingIntent);
  
          //---100ms delay, vibrate for 250ms, pause for 100ms and then vibrate for 500ms---
          notif.vibrate = new long[] {100, 250, 100, 500};
          nm.notify(notificationID, notif);//-----the first parameter here is getting an error
      }
  }
  </code></pre>
  
  <p>Any ideas that could hear me would be greatly appreciated, I have tried cleaning my build but that didnt do anything to help.</p>