How to create alarm when calendar event is created?

I have inserted an event in a calendar. The time of event created must also be created with alarm of the same time to ring. How to do it? I have used following code and it gives folowing error.

I get following error when i use the following code: Main Activity:

    Calendar caln = Calendar.getInstance();

    caln.add(Calendar.SECOND, 2);
    Intent intent = new Intent(ToDoApplicationActivity.this, AlarmReceiver.class);
    intent.putExtra("alarm_message", title1);

    PendingIntent sender = PendingIntent.getBroadcast(this, 192837, intent, PendingIntent.FLAG_UPDATE_CURRENT);

    AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
    am.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), sender);
    startActivity(intent);

OnReceive method overrided:

public void onReceive(Context context, Intent intent) {
   try {
     Bundle bundle = intent.getExtras();
     String message = bundle.getString("alarm_message");

   开发者_开发知识库  Intent newIntent = new Intent(context, ToDoApplicationActivity.class);
     newIntent.putExtra("alarm_message", message);
     newIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
     context.startActivity(newIntent);
    } catch (Exception e) {
     Toast.makeText(context, "There was an error somewhere, but we still received an alarm", Toast.LENGTH_SHORT).show();
     e.printStackTrace();

    }
 }

ERROR got:

android.content.ActivityNotFoundException: Unable to find explicit activity class {com.android.todoapplication/android.todoapplication.AlarmReceiver}; have you declared this activity in your AndroidManifest.xml?

Any Help is highly appreciated and thanks in advance...

Try to add your activity "AlarmReceiver" in your AndroidManifest.xml.
If your activity extends an Android Receiver (E.g: BroadcastReceiver), Add it like this :

<application android:label="@string/app_name" ...>
  ...

  <receiver android:name=".AlarmReceiver" android:process=":remote" />
</application>

else

<application android:label="@string/app_name" ...>
  ...

  <activity android:name=".AlarmReceiver"/>
</application>