Java tutorial
/* * Copyright 2013 Google Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.gridtelefon; import com.google.android.gms.common.ConnectionResult; import com.google.android.gms.common.GooglePlayServicesUtil; import com.google.android.gms.gcm.GoogleCloudMessaging; import android.app.Activity; import android.content.Context; import android.content.SharedPreferences; import android.content.pm.PackageInfo; import android.content.pm.PackageManager.NameNotFoundException; import android.os.AsyncTask; import android.os.Bundle; import android.util.Log; import android.view.View; import android.widget.TextView; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.util.ArrayList; import java.util.List; import java.util.concurrent.atomic.AtomicInteger; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; /** * Main UI for the demo app. */ public class DemoActivity extends Activity { public static final String EXTRA_MESSAGE = "message"; public static final String PROPERTY_REG_ID = "registration_id"; private static final String PROPERTY_APP_VERSION = "appVersion"; private static final int PLAY_SERVICES_RESOLUTION_REQUEST = 9000; /** * Substitute you own sender ID here. This is the project number you got * from the API Console, as described in "Getting Started." */ String SENDER_ID = "193853672735"; /** * Tag used on log messages. */ static final String TAG = "GCM Demo"; TextView mDisplay; GoogleCloudMessaging gcm; AtomicInteger msgId = new AtomicInteger(); Context context; String regid; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mDisplay = (TextView) findViewById(R.id.display); context = getApplicationContext(); // Check device for Play Services APK. If check succeeds, proceed with GCM registration. if (checkPlayServices()) { gcm = GoogleCloudMessaging.getInstance(this); regid = getRegistrationId(context); if (regid.isEmpty()) { registerInBackground(); } } else { Log.i(TAG, "No valid Google Play Services APK found."); } } @Override protected void onResume() { super.onResume(); // Check device for Play Services APK. checkPlayServices(); } /** * Check the device to make sure it has the Google Play Services APK. If * it doesn't, display a dialog that allows users to download the APK from * the Google Play Store or enable it in the device's system settings. */ 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; } /** * Stores the registration ID and the app versionCode in the application's * {@code SharedPreferences}. * * @param context application's context. * @param regId registration ID */ private void storeRegistrationId(Context context, String regId) { final SharedPreferences prefs = getGcmPreferences(context); int appVersion = getAppVersion(context); Log.i(TAG, "Saving regId on app version " + appVersion); SharedPreferences.Editor editor = prefs.edit(); editor.putString(PROPERTY_REG_ID, regId); editor.putInt(PROPERTY_APP_VERSION, appVersion); editor.commit(); } /** * Gets the current registration ID for application on GCM service, if there is one. * <p> * If result is empty, the app needs to register. * * @return registration ID, or empty string if there is no existing * registration ID. */ private String getRegistrationId(Context context) { final SharedPreferences prefs = getGcmPreferences(context); String registrationId = prefs.getString(PROPERTY_REG_ID, ""); if (registrationId.isEmpty()) { Log.i(TAG, "Registration not found."); return ""; } // Check if app was updated; if so, it must clear the registration ID // since the existing regID is not guaranteed to work with the new // app version. int registeredVersion = prefs.getInt(PROPERTY_APP_VERSION, Integer.MIN_VALUE); int currentVersion = getAppVersion(context); if (registeredVersion != currentVersion) { Log.i(TAG, "App version changed."); return ""; } return registrationId; } /** * Registers the application with GCM servers asynchronously. * <p> * Stores the registration ID and the app versionCode in the application's * shared preferences. */ private void registerInBackground() { new AsyncTask<Void, Void, String>() { @Override protected String doInBackground(Void... params) { String msg = ""; try { if (gcm == null) { gcm = GoogleCloudMessaging.getInstance(context); } regid = gcm.register(SENDER_ID); msg = "Device registered, registration ID=" + regid; // You should send the registration ID to your server over HTTP, so it // can use GCM/HTTP or CCS to send messages to your app. sendRegistrationIdToBackend(); // For this demo: we don't need to send it because the device will send // upstream messages to a server that echo back the message using the // 'from' address in the message. // Persist the regID - no need to register again. storeRegistrationId(context, regid); } catch (IOException ex) { msg = "Error :" + ex.getMessage(); // If there is an error, don't just keep trying to register. // Require the user to click a button again, or perform // exponential back-off. } return msg; } @Override protected void onPostExecute(String msg) { mDisplay.append(msg + "\n"); } }.execute(null, null, null); } // Send an upstream message. public void onClick(final View view) { if (view == findViewById(R.id.send)) { new AsyncTask<Void, Void, String>() { @Override protected String doInBackground(Void... params) { String msg = ""; try { Bundle data = new Bundle(); data.putString("my_message", "Hello World"); data.putString("my_action", "com.gridtelefon.ECHO_NOW"); String id = Integer.toString(msgId.incrementAndGet()); gcm.send(SENDER_ID + "@gcm.googleapis.com", id, data); msg = "Sent message"; } catch (IOException ex) { msg = "Error :" + ex.getMessage(); } return msg; } @Override protected void onPostExecute(String msg) { mDisplay.append(msg + "\n"); } }.execute(null, null, null); } else if (view == findViewById(R.id.clear)) { mDisplay.setText(""); } } @Override protected void onDestroy() { super.onDestroy(); } /** * @return Application's version code from the {@code PackageManager}. */ private static int getAppVersion(Context context) { try { PackageInfo packageInfo = context.getPackageManager().getPackageInfo(context.getPackageName(), 0); return packageInfo.versionCode; } catch (NameNotFoundException e) { // should never happen throw new RuntimeException("Could not get package name: " + e); } } /** * @return Application's {@code SharedPreferences}. */ private SharedPreferences getGcmPreferences(Context context) { // This sample app persists the registration ID in shared preferences, but // how you store the regID in your app is up to you. return getSharedPreferences(DemoActivity.class.getSimpleName(), Context.MODE_PRIVATE); } /** * Sends the registration ID to your server over HTTP, so it can use GCM/HTTP or CCS to send * messages to your app. Not needed for this demo since the device sends upstream messages * to a server that echoes back the message using the 'from' address in the message. */ private void sendRegistrationIdToBackend() { // Your implementation here. String url = "http://www.yourwebsitename.com/getregistrationid.php"; List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("regid", regid)); DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); try { httpPost.setEntity(new UrlEncodedFormEntity(params)); } catch (UnsupportedEncodingException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } try { HttpResponse httpResponse = httpClient.execute(httpPost); } catch (ClientProtocolException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }