quick cheat-paper for GCM setup

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.genyware.whereareyou"
          android:versionCode="1"
          android:versionName="1.0">
    <uses-sdk android:minSdkVersion="15"/>
    <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.WAKE_LOCK"/>
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE"/>

    <permission android:name=".permission.C2D_MESSAGE"
                android:protectionLevel="signature"/>
    <uses-permission android:name="android.permission.C2D_MESSAGE"/>

    <application android:label="@string/app_name" android:icon="@drawable/ic_launcher">
        <activity android:name="AcStarter"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <receiver android:name="com.google.android.gms.gcm.GcmReceiver"
                  android:exported="true"
                  android:permission="com.google.android.c2dm.permission.SEND">
            <intent-filter>
                <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
                <action android:name="com.google.android.c2dm.intent.RECEIVE"/>
                <category android:name="com.genyware.whereareyou"/>
            </intent-filter>
        </receiver>

        <service android:name=".MyInstanceIDListenerService" android:exported="false">
            <intent-filter>
                <action android:name="com.google.android.gms.iid.InstanceID"/>
            </intent-filter>
        </service>

    </application>
</manifest>

FILES_LIST.txt

1. google-services.json // https://developers.google.com/identity/sign-in/android/start
2. AndroidManifest.xml
3. RegistrationIntentService.java
4. MyInstanceIDListenerService.java
5. 

google-services.json

{"project_info":{"project_id":"where-are-you","project_number":"<deleted>","name":"where-are-you"},"client":[{"client_info":{"mobilesdk_app_id":"1:<deleted>:android:<deleted>","client_id":"android:com.genyware.whereareyou","client_type":1,"android_client_info":{"package_name":"com.genyware.whereareyou"}},"oauth_client":[],"api_key":[],"services":{"analytics_service":{"status":1},"cloud_messaging_service":{"status":2,"apns_config":[]},"appinvite_service":{"status":1,"other_platform_oauth_client":[]},"google_signin_service":{"status":1},"ads_service":{"status":1}}}],"client_info":[],"ARTIFACT_VERSION":"1"}

MyInstanceIDListenerService.java

package com.genyware.whereareyou;

import android.content.Intent;

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

public class MyInstanceIDListenerService extends InstanceIDListenerService {

    private static final String TAG = "MyInstanceIDLS";

    /**
     * Called if InstanceID token is updated. This may occur if the security of
     * the previous token had been compromised. This call is initiated by the
     * InstanceID provider.
     */
    // [START refresh_token]
    @Override
    public void onTokenRefresh() {
        // Fetch updated Instance ID token and notify our app's server of any changes (if applicable).
        Intent intent = new Intent(this, RegistrationIntentService.class);
        startService(intent);
    }
    // [END refresh_token]
}

RegistrationIntentService.java

package com.genyware.whereareyou;

import android.app.IntentService;
import android.content.Intent;
import android.content.SharedPreferences;
import android.preference.PreferenceManager;
import android.support.v4.content.LocalBroadcastManager;
import android.util.Log;

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

/**
 * Created by user on 23.10.15.
 */
public class RegistrationIntentService extends IntentService {

    public static final String SENT_TOKEN_TO_SERVER = "SENT_TOKEN_TO_SERVER_KEY";
    public static final String REGISTRATION_COMPLETE = "REGISTRATION_COMPLETE_KEY";

    // give your server registration url here
    static final String SERVER_URL = "http://10.0.2.2/gcm_server_php/register.php";

    // Google project id
    static final String SENDER_ID = " ";

    static final String SERVER_API_KEY = " ";

    private static final String TAG = "RegIntentService";
    private static final String[] TOPICS = {"global"};


    public RegistrationIntentService() {
        super(TAG);
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);

        try {
            // [START register_for_gcm]
            // Initially this call goes out to the network to retrieve the token, subsequent calls
            // are local.
            // [START get_token]
            InstanceID instanceID = InstanceID.getInstance(this);
            // R.string.gcm_defaultSenderId (the Sender ID) is typically derived from google-services.json.
            // See https://developers.google.com/cloud-messaging/android/start for details on this file.
            String token = instanceID.getToken(SENDER_ID,
                    GoogleCloudMessaging.INSTANCE_ID_SCOPE, null);
            // [END get_token]
            Log.i(TAG, "GCM Registration Token: " + token);

            // TODO: Implement this method to send any registration to your app's servers.
            sendRegistrationToServer(token);

            //
            // WUT?
            //
            // Subscribe to topic channels
            //subscribeTopics(token);

            // You should store a boolean that indicates whether the generated token has been
            // sent to your server. If the boolean is false, send the token to your server,
            // otherwise your server should have already received the token.
            sharedPreferences.edit().putBoolean(SENT_TOKEN_TO_SERVER, true).apply();
            // [END register_for_gcm]
        } catch (Exception e) {
            Log.d(TAG, "Failed to complete token refresh", e);
            // If an exception happens while fetching the new token or updating our registration data
            // on a third-party server, this ensures that we'll attempt the update at a later time.
            sharedPreferences.edit().putBoolean(SENT_TOKEN_TO_SERVER, false).apply();
        }
        // Notify UI that registration has completed, so the progress indicator can be hidden.
        Intent registrationComplete = new Intent(REGISTRATION_COMPLETE);
        LocalBroadcastManager.getInstance(this).sendBroadcast(registrationComplete);
    }

    private void sendRegistrationToServer(String token) {
        //todo: implement
    }

}