(Android™) Reading Unread POP3 Email

The POP3 protocol does not provide the ability to ask the server which emails are "unread". Furthermore, a pure POP3 server does not even keep this information. Some servers, such as Exchange Server, expose both POP3 and IMAP interfaces. In these cases, information about read/unread status exists on the server, but it is only available via the IMAP protocol. Email clients such as Outlook and Thunderbird keep read/unread information on the client computer. This example demonstrates how UIDLs can be saved to track and read "unread" email.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // The mailman object is used for receiving (POP3) 
    // and sending (SMTP) email.
    CkMailMan mailman = new CkMailMan();

    // Set the POP3 server's hostname
    mailman.put_MailHost("pop.someMailServer.com");

    // Set the POP3 login/password.
    mailman.put_PopUsername("***");
    mailman.put_PopPassword("***");

    // You may keep a list of already-seen UIDLs in a text file:
    // If this is the first time you're running this example,
    // create an empty text file named "seenUidls.txt"
    CkStringArray saSeenUidls = new CkStringArray();
    boolean success = saSeenUidls.LoadFromFile("seenUidls.txt");
    if (success != true) {
        Log.i(TAG, "failed to load seenUidls.txt");
        return;
        }

    // Get the complete list of UIDLs on the mail server.
    CkStringArray saUidls = mailman.GetUidls();
    if (mailman.get_LastMethodSuccess() == false) {
        Log.i(TAG, mailman.lastErrorText());
        return;
        }

    // Create a new string array object (it's an object, not an actual array)
    // and add the UIDLs from saUidls that aren't already seen.
    CkStringArray saUnseenUidls = new CkStringArray();

    int i = 0;
    int n = saUidls.get_Count();
    while (i < n) {
        if (saSeenUidls.Contains(saUidls.getString(i)) != true) {
            success = saUnseenUidls.Append(saUidls.getString(i));
            }

        i = i + 1;
        }

    if (saUnseenUidls.get_Count() == 0) {
        Log.i(TAG, "No unseen emails!");

        return;
        }

    // Download in full the unseen emails:
    CkEmailBundle bundle = mailman.FetchMultiple(saUnseenUidls);
    if (mailman.get_LastMethodSuccess() == false) {
        Log.i(TAG, mailman.lastErrorText());

        return;
        }

    CkEmail email;
    i = 0;
    while (i < bundle.get_MessageCount()) {
        email = bundle.GetEmail(i);
        Log.i(TAG, email.ck_from());
        Log.i(TAG, email.subject());
        Log.i(TAG, "----");

        i = i + 1;
        }

    // Save saUidls to "seenUidls.txt"
    success = saUidls.SaveToFile("seenUidls.txt");


  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}