I’m trying to implement a simple Facebook chat application on Android. It lets the user login, after which the app opens a new ListActivity enumerating the user’s online contacts, and upon clicking on an item, another Activity opens where their conversation will take place.
The first screen where the user logs in is called MainActivity. It contains two EditTexts: one for the FB username, and the other for password. There are also two buttons: Clear, which empties theEditTexts, and OK, which upon click, executes the following AsyncTask via new LoginTask().execute():
class LoginTask extends AsyncTask<Void, Void, Void> {
private ProgressDialog loading;
@Override
protected void onPreExecute() {
loading = ProgressDialog.show(MainActivity.this, "", "Loading...");
}
@Override
protected Void doInBackground(Void... params) {
// setup XMPP connection
ConnectionConfiguration config = new ConnectionConfiguration(
"chat.facebook.com", 5222, "chat.facebook.com");
config.setDebuggerEnabled(true);
config.setSASLAuthenticationEnabled(true); // TRUE for fb
conn = new XMPPConnection(config);
try {
// attempt login
conn.connect();
SASLAuthentication.supportSASLMechanism("PLAIN", 0);
conn.login(login_field.getText().toString(),
pwd_field.getText().toString(), "");
Log.d("TRACE", "isAuthenticated? " + conn.isAuthenticated());
// list online contacts
Roster roster = conn.getRoster();
Collection<RosterEntry> entries = roster.getEntries();
Log.d("TRACE", "entries.size()=" + entries.size());
for (RosterEntry e : entries) {
Log.d("PRESENCE", e.getUser() + "=" + roster.getPresence(e.getUser()).isAvailable());
if (roster.getPresence(e.getUser()).isAvailable()) {
HashMap<String, String> contact = new HashMap<String, String>();
contact.put(NAME_KEY, e.getName());
contact.put(USERJID_KEY, e.getUser());
Log.d("ADD", "NAME_KEY=" + e.getName() + " USERJID_KEY=" + e.getUser());
contacts.add(contact);
}
}
Collections.sort(contacts, new ContactComparator()); // sort alphabetically
Log.d("TRACE", "MainActivity.contacts.size(): " + contacts.size());
Intent in = new Intent(MainActivity.this, ContactList.class);
startActivity(in);
} catch (Exception e) {
Log.d("EXCEPTION", e.toString());
}
return null;
}
@Override
protected void onPostExecute(Void result) {
loading.dismiss();
}
}
My problem is that whenever the second screen is opened, the ListView often doesn’t show anythying,BUT IT SOMETIMES DOES. I decided to add log messages to the part where I’m retrieving the contacts via conn.getRoster() and I found out that most of the time, a call toconn.getRoster().getEntries.size() returns a zero, but when I actually login to Facebook via browser, I can see that I do have online contacts. What I don’t understand, though, is why it sometimes returns the correct number, but only once in almost every billion times I run the application.
Somebody help, please? This app’s due in four hours and I don’t know what to do anymore since there seems to be nothing wrong with my code.