Android update UI from C2DM registration class

Question

I have got C2DM setup and working. It also sends the users ID to my server so I can then send messages to it. However I am struggling updating the UI alerting the user with the status of their registration. The problem I have is that the registration is handled in a class which is not an activity, so I am struggling to figure out how to alert the user.

I have a class 'RegistrationScreen' which has the following:

import android.app.Activity;
import android.app.Dialog;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class RegistrationScreen extends Activity {


    public static int status;
    public static String userID;
    public static String regPass;
    public static int bankID=201;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.registrationscreen);

        Button btn1 = (Button)findViewById(R.id.registerSubmitButton);
        btn1.setOnClickListener(new OnClickListener() 
        {

            @Override
            public void onClick(View arg0) {
                //Get data from form
                final EditText userIdText = (EditText) findViewById(R.id.userID);
                userID = userIdText.getText().toString();

                final EditText userPasswordText = (EditText) findViewById(R.id.userPassword);
                regPass = userPasswordText.getText().toString();


                register();
            }

        });
    }

    protected Dialog onCreateDialog(int id) {
        switch (id) {
        case 0:
            Dialog superSimpleDlg = new Dialog(this);
            superSimpleDlg.setTitle("blah");
            return superSimpleDlg;

        }
        return null;
    }
    private void register() {
        status=1; //1= being processed
        String emailOfSender ="*removed*";
        Intent registrationIntent = new Intent("com.google.android.c2dm.intent.REGISTER");
        registrationIntent.putExtra("app", PendingIntent.getBroadcast(this, 0, new Intent(), 0)); // boilerplate
        registrationIntent.putExtra("sender", emailOfSender);
        startService(registrationIntent);

        //        while(status==1){
        //          
        //        }

        showDialog(0);
        //TODO Show "Registering..." dialogue???

    }
}

This is successfully invoking the registration process. However I would like to show a "processing dialog" whilst it is going through the registration process and a "confirmation dialogue" when it has successfully registered.

I have another class 'C2DMReceiver' which handles the registration with the google servers and also uses sockets to register onto my own servers.

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.util.Log;

public class C2DMReceiver extends BroadcastReceiver {
    private static String KEY = "c2dmPref";
    private static String REGISTRATION_KEY = "registrationKey";

    private Context context;
    @Override
    public void onReceive(Context context, Intent intent) {
        this.context = context;
        if (intent.getAction().equals("com.google.android.c2dm.intent.REGISTRATION")) {
            handleRegistration(context, intent);
        } else if (intent.getAction().equals("com.google.android.c2dm.intent.RECEIVE")) {
            handleMessage(context, intent);
        }
    }

    private void handleRegistration(Context context, Intent intent) {
        String registration = intent.getStringExtra("registration_id");
        if (intent.getStringExtra("error") != null) {
            // Registration failed, should try again later.
            Log.d("c2dm", "registration failed");
            String error = intent.getStringExtra("error");
            if(error == "SERVICE_NOT_AVAILABLE"){
                Log.d("c2dm", "SERVICE_NOT_AVAILABLE");
            }else if(error == "ACCOUNT_MISSING"){
                Log.d("c2dm", "ACCOUNT_MISSING");
            }else if(error == "AUTHENTICATION_FAILED"){
                Log.d("c2dm", "AUTHENTICATION_FAILED");
            }else if(error == "TOO_MANY_REGISTRATIONS"){
                Log.d("c2dm", "TOO_MANY_REGISTRATIONS");
            }else if(error == "INVALID_SENDER"){
                Log.d("c2dm", "INVALID_SENDER");
            }else if(error == "PHONE_REGISTRATION_ERROR"){
                Log.d("c2dm", "PHONE_REGISTRATION_ERROR");
            }
        } else if (intent.getStringExtra("unregistered") != null) {
            // unregistration done, new messages from the authorized sender will be rejected
            Log.d("c2dm", "unregistered");

        } else if (registration != null) {
            Log.d("c2dm", registration);
            Editor editor =
                    context.getSharedPreferences(KEY, Context.MODE_PRIVATE).edit();
            editor.putString(REGISTRATION_KEY, registration);
            editor.commit();
            registerWithServer(registration);
            // Send the registration ID to the 3rd party site that is sending the messages.
            // This should be done in a separate thread.
            // When done, remember that all registration is done.
        }
    }

    private void handleMessage(Context context, Intent intent)
    {
        Bundle extras = intent.getExtras();
        if (extras != null) {
            // String blah = (String) extras.get("POSTFIELDS");
            Log.d("c2dm", "recieved: "+extras.getString("message"));

        }

    }

    private void registerWithServer(String c2dmID) {
        String hostname = "10.0.2.2";
        int port = 54321;

        socketClient client = new socketClient(hostname, port);
        String message = client.sendMessage("registerRSA|c2dmID="+c2dmID+",userID="+RegistrationScreen.userID+",bankID="+RegistrationScreen.bankID+",passcode="+RegistrationScreen.regPass+",deviceID=njfdfdsj389rfb,timestamp=00000,");
        Log.v("SOCKETCLIENT",message);

        //Do actions on input string
        String tokens[] = message.split("\\|");
        System.out.println(tokens[0]);
        //

        if (tokens[0].equals("success")) {
            RegistrationScreen.status=100;

        } else if (tokens[0].equals("error")) {
            int errorID = 0;
            String friendlyErrorMessage = null;
            //Split the , then the =
            String variables[] = tokens[1].split(",");
            for (int i=0; i<variables.length; i++) {
                String tempSplit[] = variables[i].split("=");
                if (tempSplit[0].equals("errorID")) {
                    errorID=Integer.parseInt(tempSplit[1]);
                } else if (tempSplit[0].equals("friendlyErrorMessage")) {
                    friendlyErrorMessage=tempSplit[1];
                } 
            }

            //Update UI to alert of error
            //TextView textViewToChange = (TextView) findViewById(R.id.registerTextHeader);
            //textViewToChange.setText("Error getting seed! (ERR" + errorID + ") " + friendlyErrorMessage);
            RegistrationScreen.status=200;

        } else {
            RegistrationScreen.status=300;

            //unknown problem
        }
    }

}

As you can see I have tried to achieve it using a while loop checking a 'status' variable, however this causes the program to hang and doesn't seem like very efficient programming.

Answer 1

You can use the SharedPreferenceListener in this case.

Once the user registration is successful, try this one:

  SharedPreferences prefs = PreferenceManager
 .getDefaultSharedPreferences(this.getApplicationContext());
 Editor edit = prefs.edit();
 edit.putBoolean("isRegistered",true).commit();

Once the user unregister is successful, try this one:

  SharedPreferences prefs = PreferenceManager
 .getDefaultSharedPreferences(this.getApplicationContext());
 Editor edit = prefs.edit();
 edit.putBoolean("isRegistered",false).commit();

And in your activity, Create a textview (or something of your preference. I'm using textview in this example). You can put this code somewhere in OnCreate();

 SharedPreferences prefs = PreferenceManager
 .getDefaultSharedPreferences(this.getApplicationContext());
 OnSharedPreferenceChangeListener listener;
 listener = new SharedPreferences.OnSharedPreferenceChangeListener() {
        @Override
        public void onSharedPreferenceChanged(SharedPreferences arg0,
        String key) {

        if (key.equalsIgnoreCase("isRegistered")) {

            Log.v("RegistrationScreen", "registration status changed");             
            if (prefs.getBoolean("isRegistered", false))
                {
                  textView.setText("Registered Successfully");
                }
                else
                {
                  textView.setText("Successfully UnRegistered");
                }
        }
    }
};
    prefs.registerOnSharedPreferenceChangeListener(listener);

Hope This Helps...