首先，我感觉在实现中PendingIntent感觉就是Intent的包装。
它的三个实例化方法：
getActivity(Context, int, Intent, int)
getService(Context, int, Intent, int)
getBroadcast(Context, int, Intent, int)
感觉是保存当前的Activity的Context，然后在外部启动Intent动作。类似于代码Context.startActivity(*, *);
常和Notification和Alarm一起使用。
代码例子：
public class BannerActivity extends Activity {
private Button b;
private NotificationManager mNotificationManager;
private Intent intent;
private PendingIntent mPendingIntent;
private Notification mNotification;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mNotificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
b = (Button)this.findViewById(R.id.b);
intent = new Intent(BannerActivity.this, Activity01.class);
mPendingIntent = PendingIntent.getActivity(BannerActivity.this, 0, intent, Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT);
mNotification = new Notification();
b.setOnClickListener(new Button.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
mNotification.icon = R.drawable.ic_launcher;
mNotification.tickerText = "通知！"; //通知在通知栏出现的时候的标题
mNotification.defaults = Notification.DEFAULT_SOUND;
// 第二个参数是打开通知栏后的标题， 第三个参数是通知内容
mNotification.setLatestEventInfo(BannerActivity.this, "通知？", "通知内容！", mPendingIntent);
mNotificationManager.notify(0, mNotification);
}
});
}
}