问题
I have built a chat application . It is working fine . both users can chat easily but where I get Stuck is if one user's app is at background and screen is off , user is unable to be notified of that received message.
What I want now is in my application is when userA sends message to userB , and userB mobile is idle but application is running in background, userB can get notification about that message. and userB can open the chat activity and read the message .
My firebase notification is working from firebase console but I don't know how to call instance id and send that to particular device from api and particular user get notification about the received message , when application screen is off and application is running in background state . How should I achieve it?
I have my firebase instance id service class here:
public class MyFirebaseInstanceIDService extends FirebaseInstanceIdService {
private static final String TAG = "MyFirebaseIIDService";
@Override
public void onTokenRefresh() {
//Getting registration token
String refreshedToken = FirebaseInstanceId.getInstance().getToken();
//Displaying token on logcat
Log.d(TAG, "Refreshed token: " + refreshedToken);
}
private void sendRegistrationToServer(String token) {
//You can implement this method to store the token on your server
//Not required for current project
}
}
Here is my MyFirebase Messaging Service Class
public class MyFirebaseMessagingService extends FirebaseMessagingService {
@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
if (remoteMessage.getNotification().getBody() != null) {
Log.e("FIREBASE", "Message Notification Body: " + remoteMessage.getNotification().getBody());
sendNotification(remoteMessage);
}
}
private void sendNotification(RemoteMessage remoteMessage) {
RemoteMessage.Notification notification = remoteMessage.getNotification();
Intent intent = new Intent(this, LoggedInView.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
PendingIntent.FLAG_ONE_SHOT);
Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
.setLargeIcon(BitmapFactory.decodeResource(getResources(),R.drawable.first_aid))
.setSmallIcon(R.drawable.first_aid)
.setContentTitle(notification.getTitle())
.setContentText(notification.getBody())
.setAutoCancel(true)
.setSound(defaultSoundUri)
.setContentIntent(pendingIntent);
NotificationManager notificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.notify(0, notificationBuilder.build());
}
}
Here is my chat Activity:
public class Chat extends AppCompatActivity {
LinearLayout layout;
ImageView sendButton,vidcall;
EditText messageArea;
ScrollView scrollView;
Firebase reference1, reference2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.act_chat);
layout = (LinearLayout)findViewById(R.id.layout1);
sendButton = (ImageView)findViewById(R.id.sendButton);
vidcall = (ImageView)findViewById(R.id.vidBtnk);
messageArea = (EditText)findViewById(R.id.messageArea);
scrollView = (ScrollView)findViewById(R.id.scrollView);
Firebase.setAndroidContext(this);
reference1 = new Firebase("https://*******.firebaseio.com/messages/" + UserDetails.username + "_" + UserDetails.chatWith);
reference2 = new Firebase("https://*******.firebaseio.com/messages/" + UserDetails.chatWith + "_" + UserDetails.username);
sendButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String messageText = messageArea.getText().toString();
if(!messageText.equals("")){
Map<String, String> map = new HashMap<String, String>();
map.put("message", messageText);
map.put("user", UserDetails.username);
reference1.push().setValue(map);
reference2.push().setValue(map);
}
messageArea.setText("");
}
});
vidcall.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startActivity(new Intent(Chat.this, ConnectActivity.class));
}
});
reference1.addChildEventListener(new ChildEventListener() {
@Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
Map map = dataSnapshot.getValue(Map.class);
String message = map.get("message").toString();
String userName = map.get("user").toString();
if(userName.equals(UserDetails.username)){
addMessageBox("You:-\n" + message, 1);
}
else{
addMessageBox(UserDetails.chatWith + ":-\n" + message, 2);
}
}
@Override
public void onChildChanged(DataSnapshot dataSnapshot, String s) {
}
@Override
public void onChildRemoved(DataSnapshot dataSnapshot) {
}
@Override
public void onChildMoved(DataSnapshot dataSnapshot, String s) {
}
@Override
public void onCancelled(FirebaseError firebaseError) {
}
});
}
// boolean doubleBackToExitPressedOnce = false;
@Override
public void onBackPressed() {
AlertDialog.Builder builder1 = new AlertDialog.Builder(Chat.this);
builder1.setMessage("CAUTION! -> Do Wish to End this Session");
builder1.setCancelable(true);
builder1.setPositiveButton(
"Yes",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
finish();
dialog.cancel();
}
});
builder1.setNegativeButton(
"No",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
});
AlertDialog alert11 = builder1.create();
alert11.show();
}
public void addMessageBox(String message, int type){
TextView textView = new TextView(Chat.this);
textView.setText(message);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
lp.setMargins(0, 0, 0, 10);
textView.setLayoutParams(lp);
if(type == 1) {
textView.setBackgroundResource(R.drawable.rounded_corner1);
}
else{
textView.setBackgroundResource(R.drawable.rounded_corner2);
}
layout.addView(textView);
scrollView.fullScroll(View.FOCUS_DOWN);
}
}
回答1:
You need a service running on background to catch the PUSH notification and show it to the user, and that's what the Firebase Notification Service provides you with. I have this one (you'll have to modify it in order to do what you want to do when a notification is showed up):
public class MyFirebaseMessagingService extends FirebaseMessagingService {
@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
if (remoteMessage.getNotification().getBody() != null) {
Log.e("FIREBASE", "Message Notification Body: " + remoteMessage.getNotification().getBody());
sendNotification(remoteMessage);
}
}
private void sendNotification(RemoteMessage remoteMessage) {
RemoteMessage.Notification notification = remoteMessage.getNotification();
Intent intent = new Intent(this, MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
PendingIntent.FLAG_ONE_SHOT);
Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
.setLargeIcon(BitmapFactory.decodeResource(getResources(),R.drawable.logo_gris))
.setSmallIcon(R.drawable.logo_gris)
.setContentTitle(notification.getTitle())
.setContentText(notification.getBody())
.setAutoCancel(true)
.setSound(defaultSoundUri)
.setContentIntent(pendingIntent);
NotificationManager notificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.notify(0, notificationBuilder.build());
}
}
回答2:
I solved this problem may it help someone ,
In order to send Notification of firebase through api to single device is as follows:
1: generate Instance Id , unique for every device
public class MyFirebaseInstanceIDService extends FirebaseInstanceIdService {
private static final String TAG = "MyFirebaseIIDService";
@Override
public void onTokenRefresh() {
//Getting registration token
String refreshedToken = FirebaseInstanceId.getInstance().getToken();
//Displaying token on logcat
Log.d(TAG, "Refreshed token: " + refreshedToken);
sendRegistrationToServer(refreshedToken);
}
private void sendRegistrationToServer(String token) {
//You can implement this method to store the token on your server
//Not required for current project
}
}
Note: you can call Instance Id from any where in your Application Like this:
String tkn = FirebaseInstanceId.getInstance().getToken();
Toast.makeText(Doc_users.this, "Current token ["+tkn+"]",
Toast.LENGTH_LONG).show();
Log.d("App", "Token ["+tkn+"]");
this token must be used to send notification to single device it is the id of the device you can store it in your firebase database
reference.child(UserDetails.username).child("token").setValue(tokun);
2:Now You can build your logic to fetch these ids and build your request
public static String makeRequest(String id) throws JSONException {
HttpURLConnection urlConnection;
JSONObject json = new JSONObject();
JSONObject info = new JSONObject();
info.put("title", "Notification Title"); // Notification title
info.put("body", "Notification body"); // Notification body
info.put("sound", "mySound"); // Notification sound
json.put("notification", info);
json.put("to","INSTANCE ID FETCHED FOR SIGNLE DEVICE HERE");
Log.e("deviceidkey==> ",id+"");
Log.e("jsonn==> ",json.toString());
String data = json.toString();
String result = null;
try {
//Connect
urlConnection = (HttpURLConnection) ((new URL("https://fcm.googleapis.com/fcm/send").openConnection()));
urlConnection.setDoOutput(true);
urlConnection.setRequestProperty("Content-Type", "application/json");
urlConnection.setRequestProperty("Authorization", "key=YOUR FIREBASE SERVER KEY");
urlConnection.setRequestMethod("POST");
urlConnection.connect();
//Write
OutputStream outputStream = urlConnection.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
writer.write(data);
writer.close();
outputStream.close();
//Read
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream(), "UTF-8"));
String line = null;
StringBuilder sb = new StringBuilder();
while ((line = bufferedReader.readLine()) != null) {
sb.append(line);
}
bufferedReader.close();
result = sb.toString();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return result;
}
Notification will generate on that single device sent from your device you can debug to put your own device key and use postman for valid request: Good Luck
回答3:
Hi I had implemented chat application using firebase messaging.
Here the steps you can implement
1) Implement sendRegistrationToServer(String token) { Make Async call to store token generated in the backend server (map user with token generated) }
2) In Chat Activity sendmessage() should message to server to secondUser()
3) By Looking at usertoken we should push notification from backend server to firebase server.
4) Implement onMessageReceived() to show notification
来源：https://stackoverflow.com/questions/41750548/show-notification-of-firebase-message-onreceived-when-app-is-in-background-throu