최신 Android Studio, Google Cloud Messaging 3.0(GCM)을 이용하여 Android 푸시 서비스 구현하기

package net.saltfactory.demo.gcm;

/**
 * Created by saltfactory on 6/8/15.
 */
public class QuickstartPreferences {

    public static final String REGISTRATION_READY = "registrationReady";
    public static final String REGISTRATION_GENERATING = "registrationGenerating";
    public static final String REGISTRATION_COMPLETE = "registrationComplete";

}

package net.saltfactory.demo.gcm;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;

public class MainActivity extends AppCompatActivity {

    private static final int PLAY_SERVICES_RESOLUTION_REQUEST = 9000;
    private static final String TAG = "MainActivity";

    private Button mRegistrationButton;
    private ProgressBar mRegistrationProgressBar;
    private BroadcastReceiver mRegistrationBroadcastReceiver;
    private TextView mInformationTextView;

    /**
     * Instance ID를 이용하여 디바이스 토큰을 가져오는 RegistrationIntentService를 실행한다.
     */
    public void getInstanceIdToken() {
        if (checkPlayServices()) {
            // Start IntentService to register this application with GCM.
            Intent intent = new Intent(this, RegistrationIntentService.class);
            startService(intent);
        }
    }

    /**
     * LocalBroadcast 리시버를 정의한다. 토큰을 획득하기 위한 READY, GENERATING, COMPLETE 액션에 따라 UI에 변화를 준다.
     */
    public void registBroadcastReceiver(){
        mRegistrationBroadcastReceiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                String action = intent.getAction();


                if(action.equals(QuickstartPreferences.REGISTRATION_READY)){
                    // 액션이 READY일 경우
                    mRegistrationProgressBar.setVisibility(ProgressBar.GONE);
                    mInformationTextView.setVisibility(View.GONE);
                } else if(action.equals(QuickstartPreferences.REGISTRATION_GENERATING)){
                    // 액션이 GENERATING일 경우
                    mRegistrationProgressBar.setVisibility(ProgressBar.VISIBLE);
                    mInformationTextView.setVisibility(View.VISIBLE);
                    mInformationTextView.setText(getString(R.string.registering_message_generating));
                } else if(action.equals(QuickstartPreferences.REGISTRATION_COMPLETE)){
                    // 액션이 COMPLETE일 경우
                    mRegistrationProgressBar.setVisibility(ProgressBar.GONE);
                    mRegistrationButton.setText(getString(R.string.registering_message_complete));
                    mRegistrationButton.setEnabled(false);
                    String token = intent.getStringExtra("token");
                    mInformationTextView.setText(token);
                }

            }
        };
    }


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        registBroadcastReceiver();

        // 토큰을 보여줄 TextView를 정의
        mInformationTextView = (TextView) findViewById(R.id.informationTextView);
        mInformationTextView.setVisibility(View.GONE);
        // 토큰을 가져오는 동안 인디케이터를 보여줄 ProgressBar를 정의
        mRegistrationProgressBar = (ProgressBar) findViewById(R.id.registrationProgressBar);
        mRegistrationProgressBar.setVisibility(ProgressBar.GONE);
        // 토큰을 가져오는 Button을 정의
        mRegistrationButton = (Button) findViewById(R.id.registrationButton);
        mRegistrationButton.setOnClickListener(new View.OnClickListener() {
            /**
             * 버튼을 클릭하면 토큰을 가져오는 getInstanceIdToken() 메소드를 실행한다.
             * @param view
             */
            @Override
            public void onClick(View view) {
                getInstanceIdToken();
            }
        });

    }

    /**
     * 앱이 실행되어 화면에 나타날때 LocalBoardcastManager에 액션을 정의하여 등록한다.
     */
    @Override
    protected void onResume() {
        super.onResume();
        LocalBroadcastManager.getInstance(this).registerReceiver(mRegistrationBroadcastReceiver,
                new IntentFilter(QuickstartPreferences.REGISTRATION_READY));
        LocalBroadcastManager.getInstance(this).registerReceiver(mRegistrationBroadcastReceiver,
                new IntentFilter(QuickstartPreferences.REGISTRATION_GENERATING));
        LocalBroadcastManager.getInstance(this).registerReceiver(mRegistrationBroadcastReceiver,
                new IntentFilter(QuickstartPreferences.REGISTRATION_COMPLETE));

    }

    /**
     * 앱이 화면에서 사라지면 등록된 LocalBoardcast를 모두 삭제한다.
     */
    @Override
    protected void onPause() {
        LocalBroadcastManager.getInstance(this).unregisterReceiver(mRegistrationBroadcastReceiver);
        super.onPause();
    }


    /**
     * Google Play Service를 사용할 수 있는 환경이지를 체크한다.
     */
    private boolean checkPlayServices() {
        int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
        if (resultCode != ConnectionResult.SUCCESS) {
            if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
                GooglePlayServicesUtil.getErrorDialog(resultCode, this,
                        PLAY_SERVICES_RESOLUTION_REQUEST).show();
            } else {
                Log.i(TAG, "This device is not supported.");
                finish();
            }
            return false;
        }
        return true;
    }
}

package net.saltfactory.demo.gcm;

import android.annotation.SuppressLint;
import android.app.IntentService;
import android.content.Intent;
import android.support.v4.content.LocalBroadcastManager;
import android.util.Log;

import com.google.android.gms.gcm.GoogleCloudMessaging;
import com.google.android.gms.iid.InstanceID;

import java.io.IOException;

/**
 * Created by saltfactory on 6/8/15.
 */
public class RegistrationIntentService extends IntentService {

    private static final String TAG = "RegistrationIntentService";

    public RegistrationIntentService() {
        super(TAG);
    }

    /**
     * GCM을 위한 Instance ID의 토큰을 생성하여 가져온다.
     * @param intent
     */
    @SuppressLint("LongLogTag")
    @Override
    protected void onHandleIntent(Intent intent) {

        // GCM Instance ID의 토큰을 가져오는 작업이 시작되면 LocalBoardcast로 GENERATING 액션을 알려 ProgressBar가 동작하도록 한다.
        LocalBroadcastManager.getInstance(this)
                .sendBroadcast(new Intent(QuickstartPreferences.REGISTRATION_GENERATING));

        // GCM을 위한 Instance ID를 가져온다.
        InstanceID instanceID = InstanceID.getInstance(this);
        String token = null;
        try {
            synchronized (TAG) {
                // GCM 앱을 등록하고 획득한 설정파일인 google-services.json을 기반으로 SenderID를 자동으로 가져온다.
                String default_senderId = getString(R.string.gcm_defaultSenderId);
                // GCM 기본 scope는 "GCM"이다.
                String scope = GoogleCloudMessaging.INSTANCE_ID_SCOPE;
                // Instance ID에 해당하는 토큰을 생성하여 가져온다.
                token = instanceID.getToken(default_senderId, scope, null);

                Log.i(TAG, "GCM Registration Token: " + token);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        // GCM Instance ID에 해당하는 토큰을 획득하면 LocalBoardcast에 COMPLETE 액션을 알린다.
        // 이때 토큰을 함께 넘겨주어서 UI에 토큰 정보를 활용할 수 있도록 했다.
        Intent registrationComplete = new Intent(QuickstartPreferences.REGISTRATION_COMPLETE);
        registrationComplete.putExtra("token", token);
        LocalBroadcastManager.getInstance(this).sendBroadcast(registrationComplete);
    }
}

package net.saltfactory.demo.gcm;

import android.content.Intent;

import com.google.android.gms.iid.InstanceIDListenerService;

/**
 * Created by saltfactory on 6/8/15.
 */
public class MyInstanceIDListenerService extends InstanceIDListenerService {

    private static final String TAG = "MyInstanceIDLS";

    @Override
    public void onTokenRefresh() {
        Intent intent = new Intent(this, RegistrationIntentService.class);
        startService(intent);
    }
}

package net.saltfactory.demo.gcm;

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.media.RingtoneManager;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.util.Log;

import com.google.android.gms.gcm.GcmListenerService;

/**
 * Created by saltfactory on 6/8/15.
 */
public class MyGcmListenerService extends GcmListenerService {

    private static final String TAG = "MyGcmListenerService";

    /**
     *
     * @param from SenderID 값을 받아온다.
     * @param data Set형태로 GCM으로 받은 데이터 payload이다.
     */
    @Override
    public void onMessageReceived(String from, Bundle data) {
        String title = data.getString("title");
        String message = data.getString("message");

        Log.d(TAG, "From: " + from);
        Log.d(TAG, "Title: " + title);
        Log.d(TAG, "Message: " + message);

        // GCM으로 받은 메세지를 디바이스에 알려주는 sendNotification()을 호출한다.
        sendNotification(title, message);
    }


    /**
     * 실제 디바에스에 GCM으로부터 받은 메세지를 알려주는 함수이다. 디바이스 Notification Center에 나타난다.
     * @param title
     * @param message
     */
    private void sendNotification(String title, String message) {
        Intent intent = new Intent(this, MainActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
                PendingIntent.FLAG_ONE_SHOT);

        Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
                .setSmallIcon(R.drawable.ic_stat_ic_notification)
                .setContentTitle(title)
                .setContentText(message)
                .setAutoCancel(true)
                .setSound(defaultSoundUri)
                .setContentIntent(pendingIntent);

        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
    }
}