This worked perfectly fine from the time I created the project. But suddenly is starts crashing. The sign up activity works fine. But this sign in activity is crashing.
The error shown by the debugger.
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.durden, PID: 7921
java.lang.NullPointerException
at com.example.durden.activity.SignInActivity.onCreate$lambda-2(SignInActivity.kt:49)
at com.example.durden.activity.SignInActivity.$r8$lambda$ZBrxDCm4vr69l-PuE690AA_KCF8(Unknown Source:0)
at com.example.durden.activity.SignInActivity$$ExternalSyntheticLambda1.onClick(Unknown Source:4)
at android.view.View.performClick(View.java:7125)
at android.view.View.performClickInternal(View.java:7102)
at android.view.View.access$3500(View.java:801)
at android.view.View$PerformClick.run(View.java:27336)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
The signin Activity
class SignInActivity : AppCompatActivity() {
// getting the references from firebase
private var auth: FirebaseAuth? = null
private var firebaseUser: FirebaseUser? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// gets the view binding of sign_in_activity
val binding = ActivitySignInBinding.inflate(layoutInflater)
setContentView(binding.root)
// ends this activity and goes to sign up page if needed
binding.gotoSignUp.setOnClickListener {
val intent = Intent(
this#SignInActivity,
SignUpActivity::class.java
)
startActivity(intent)
finish()
}
binding.btnSignIn.setOnClickListener {
// storing the entered email and password
val email = binding.SImail.text.toString()
val password = binding.SIpass.text.toString()
// checks if the values are entered
if (TextUtils.isEmpty(email) && TextUtils.isEmpty(password)) {
Toast.makeText(applicationContext,"email and password are required", Toast.LENGTH_SHORT).show()
}
// signs in the user using firebase data
else {
auth!!.signInWithEmailAndPassword(email, password)
.addOnCompleteListener(this) {
if (it.isSuccessful) {
binding.SImail.setText("")
binding.SIpass.setText("")
// after sign in takes to user page
val intent = Intent(
this#SignInActivity,
UserActivity::class.java
)
startActivity(intent)
finish()
}
else {
Toast.makeText( applicationContext, "Invalid password or email", Toast.LENGTH_SHORT).show()
}
}
}
}
}
}
Firebase Authentication causing Android fatal exception
This sounds similar to my problem but still, I couldn't figure why it happens so.
You never initialize auth, which means that by the time you execute auth!!.signInWithEmailAndPassword(email, password) you get an exception.
Initialize auth like shown in step 2 here in your onCreate to prevent the error.
// Initialize Firebase Auth
auth = Firebase.auth
NullPointerExceptions are very common, so I highly recommend learning how to troubleshoot these yourself. For that, check out:
What is the Kotlin double-bang (!!) operator?
Unfortunately MyApp has stopped. How can I solve this?
What is a NullPointerException, and how do I fix it?
You are inflating the view twice, which is just wrong:
val binding = ActivitySignInBinding.inflate(layoutInflater)
// setContentView(binding.root)
I have been trying to read the official docs and guides about how to send message from one device to another. I have saved registration token of both devices in the Real Time Database, thus I have the registration token of another device.
I have tried the following way to send the message
RemoteMessage message = new RemoteMessage.Builder(getRegistrationToken())
.setMessageId(incrementIdAndGet())
.addData("message", "Hello")
.build();
FirebaseMessaging.getInstance().send(message);
However this is not working. The other device doesn't receive any message. I am not even sure, if I can use upstream message sending to conduct device to device communication.
PS: I just want to know if device-to-device messaging is possible using FCM? If yes, then is the code I used have some issue? If yes, then what is the correct way.
Update:
My question was to ask whether device to device messaging without using any separate server other than firebase could messaging is possible or not, if yes than how, since there's no documentation about it. I do not understand what is left to explain here? Anyways I got the answer and will update it as an answer once the question gets reopened.
Firebase has two features to send messages to devices:
the Notifications panel in your Firebase Console allows you to send notifications to specific devices, groups of users, or topics that users subscribed to.
by calling Firebase Cloud Messaging API, you can send messages with whatever targeting strategy you prefer. Calling the FCM API requires access to your Server key, which you should never expose on client devices. That's why you should always run such code on an app server.
The Firebase documentation shows this visually:
Sending messages from one device directly to another device is not supported through the Firebase Cloud Messaging client-side SDKs.
Update: I wrote a blog post detailing how to send notifications between Android devices using Firebase Database, Cloud Messaging and Node.js.
Update 2: You can now also use Cloud Functions for Firebase to send messages securely, without spinning up a server. See this sample use-case to get started. If you don't want to use Cloud Functions, you can run the same logic on any trusted environment you already have, such as your development machine, or a server you control.
Warning There is a very important reason why we don't mention this approach anywhere. This exposes your server key in the APK that
you put on every client device. It can (and thus will) be taken from
there and may lead to abuse of your project. I highly recommend
against taking this approach, except for apps that you only put on
your own devices. – Frank van Puffelen
Ok, so the answer by Frank was correct that Firebase does not natively support device to device messaging. However there's one loophole in that. The Firebase server doesn't identify whether you have send the request from an actual server or are you doing it from your device.
So all you have to do is send a Post Request to Firebase's messaging server along with the Server Key. Just keep this in mind that the server key is not supposed to be on the device, but there's no other option if you want device-to-device messaging using Firebase Messaging.
I am using OkHTTP instead of default way of calling the Rest API. The code is something like this -
public static final String FCM_MESSAGE_URL = "https://fcm.googleapis.com/fcm/send";
OkHttpClient mClient = new OkHttpClient();
public void sendMessage(final JSONArray recipients, final String title, final String body, final String icon, final String message) {
new AsyncTask<String, String, String>() {
#Override
protected String doInBackground(String... params) {
try {
JSONObject root = new JSONObject();
JSONObject notification = new JSONObject();
notification.put("body", body);
notification.put("title", title);
notification.put("icon", icon);
JSONObject data = new JSONObject();
data.put("message", message);
root.put("notification", notification);
root.put("data", data);
root.put("registration_ids", recipients);
String result = postToFCM(root.toString());
Log.d(TAG, "Result: " + result);
return result;
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
try {
JSONObject resultJson = new JSONObject(result);
int success, failure;
success = resultJson.getInt("success");
failure = resultJson.getInt("failure");
Toast.makeText(getCurrentActivity(), "Message Success: " + success + "Message Failed: " + failure, Toast.LENGTH_LONG).show();
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getCurrentActivity(), "Message Failed, Unknown error occurred.", Toast.LENGTH_LONG).show();
}
}
}.execute();
}
String postToFCM(String bodyString) throws IOException {
RequestBody body = RequestBody.create(JSON, bodyString);
Request request = new Request.Builder()
.url(FCM_MESSAGE_URL)
.post(body)
.addHeader("Authorization", "key=" + SERVER_KEY)
.build();
Response response = mClient.newCall(request).execute();
return response.body().string();
}
I hope Firebase will come with a better solution in future. But till then, I think this is the only way. The other way would be to send topic message or group messaging. But that was not in the scope of the question.
Update:
The JSONArray is defined like this -
JSONArray regArray = new JSONArray(regIds);
regIds is a String array of registration ids, you want to send this message to. Keep in mind that the registration ids must always be in an array, even if you want it to send to a single recipient.
I have also been using direct device to device gcm messaging in my prototype. It has been working very well. We dont have any server. We exchange GCM reg id using sms/text and then communicate using GCM after that. I am putting here code related to GCM handling
**************Sending GCM Message*************
//Sends gcm message Asynchronously
public class GCM_Sender extends IntentService{
final String API_KEY = "****************************************";
//Empty constructor
public GCM_Sender() {
super("GCM_Sender");
}
//Processes gcm send messages
#Override
protected void onHandleIntent(Intent intent) {
Log.d("Action Service", "GCM_Sender Service Started");
//Get message from intent
String msg = intent.getStringExtra("msg");
msg = "\"" + msg + "\"";
try{
String ControllerRegistrationId = null;
//Check registration id in db
if(RegistrationIdAdapter.getInstance(getApplicationContext()).getRegIds().size() > 0 ) {
String controllerRegIdArray[] = RegistrationIdAdapter.getInstance(getApplicationContext()).getRegIds().get(1);
if(controllerRegIdArray.length>0)
ControllerRegistrationId = controllerRegIdArray[controllerRegIdArray.length-1];
if(!ControllerRegistrationId.equalsIgnoreCase("NULL")){
// 1. URL
URL url = new URL("https://android.googleapis.com/gcm/send");
// 2. Open connection
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
// 3. Specify POST method
urlConnection.setRequestMethod("POST");
// 4. Set the headers
urlConnection.setRequestProperty("Content-Type", "application/json");
urlConnection.setRequestProperty("Authorization", "key=" + API_KEY);
urlConnection.setDoOutput(true);
// 5. Add JSON data into POST request body
JSONObject obj = new JSONObject("{\"time_to_live\": 0,\"delay_while_idle\": true,\"data\":{\"message\":" + msg + "},\"registration_ids\":[" + ControllerRegistrationId + "]}");
// 6. Get connection output stream
OutputStreamWriter out = new OutputStreamWriter(urlConnection.getOutputStream());
out.write(obj.toString());
out.close();
// 6. Get the response
int responseCode = urlConnection.getResponseCode();
BufferedReader in = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null){
response.append(inputLine);
}
in.close();
Log.d("GCM getResponseCode:", new Integer(responseCode).toString());
}else{
Log.d("GCM_Sender:","Field REGISTRATION_TABLE is null");
}
}else {
Log.d("GCM_Sender:","There is no Registration ID in DB ,please sync devices");
}
} catch (Exception e) {
e.printStackTrace();
//MessageSender.getInstance().sendMessage(msg, Commands.SMS_MESSAGE);
}
}
//Called when service is no longer alive
#Override
public void onDestroy() {
super.onDestroy();
//Do a log that GCM_Sender service has been destroyed
Log.d("Action Service", "GCM_Sender Service Destroyed");
}
}
**************Receiving GCM Message*************
public class GCM_Receiver extends WakefulBroadcastReceiver {
public static final String RETRY_ACTION ="com.google.android.c2dm.intent.RETRY";
public static final String REGISTRATION ="com.google.android.c2dm.intent.REGISTRATION";
public SharedPreferences preferences;
//Processes Gcm message .
#Override
public void onReceive(Context context, Intent intent) {
ComponentName comp = new ComponentName(context.getPackageName(),
GCMNotificationIntentService.class.getName());
//Start GCMNotificationIntentService to handle gcm message asynchronously
startWakefulService(context, (intent.setComponent(comp)));
setResultCode(Activity.RESULT_OK);
/*//Check if DatabaseService is running .
if(!DatabaseService.isServiceRunning) {
Intent dbService = new Intent(context,DatabaseService.class);
context.startService(dbService);
}*/
//Check if action is RETRY_ACTION ,if it is then do gcm registration again .
if(intent.getAction().equals(RETRY_ACTION)) {
String registrationId = intent.getStringExtra("registration_id");
if(TextUtils.isEmpty(registrationId)){
DeviceRegistrar.getInstance().register(context);
}else {
//Save registration id to prefs .
preferences = PreferenceManager.getDefaultSharedPreferences(context);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("BLACKBOX_REG_ID",registrationId);
editor.commit();
}
} else if (intent.getAction().equals(REGISTRATION)) {
}
}
}
//Processes gcm messages asynchronously .
public class GCMNotificationIntentService extends IntentService{
public static final int NOTIFICATION_ID = 1;
private NotificationManager mNotificationManager;
String gcmData;
private final String TAG = "GCMNotificationIntentService";
//Constructor with super().
public GCMNotificationIntentService() {
super("GcmIntentService");
}
//Called when startService() is called by its Client .
//Processes gcm messages .
#Override
protected void onHandleIntent(Intent intent) {
Log.d("GCMNotificationIntentService", "GCMNotificationIntentService Started");
Bundle extras = intent.getExtras();
//Get instance of GoogleCloudMessaging .
GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);
//Get gcm message type .
String messageType = gcm.getMessageType(intent);
if (!extras.isEmpty()) {
if (GoogleCloudMessaging.MESSAGE_TYPE_SEND_ERROR
.equals(messageType)) {
sendNotification("Send error: " + extras.toString());
} else if (GoogleCloudMessaging.MESSAGE_TYPE_DELETED
.equals(messageType)) {
sendNotification("Deleted messages on server: "
+ extras.toString());
} else if (GoogleCloudMessaging.MESSAGE_TYPE_MESSAGE
.equals(messageType)) {
Log.i(TAG, "Completed work # " + SystemClock.elapsedRealtime());
gcmData = extras.getString("message");
Intent actionService = new Intent(getApplicationContext(),Action.class);
actionService.putExtra("data", gcmData);
//start Action service .
startService(actionService);
//Show push notification .
sendNotification("Action: " + gcmData);
//Process received gcmData.
Log.d(TAG,"Received Gcm Message from Controller : " + extras.getString("message"));
}
}
GCM_Receiver.completeWakefulIntent(intent);
}
//Shows notification on device notification bar .
private void sendNotification(String msg) {
mNotificationManager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
Intent notificationIntent = new Intent(this, BlackboxStarter.class);
//Clicking on GCM notification add new layer of app.
notificationIntent.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,notificationIntent, PendingIntent.FLAG_CANCEL_CURRENT);
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(
this).setSmallIcon(R.drawable.gcm_cloud)
.setContentTitle("Notification from Controller")
.setStyle(new NotificationCompat.BigTextStyle().bigText(msg))
.setContentText(msg);
mBuilder.setContentIntent(contentIntent);
mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
//Play default notification
try {
Uri notification = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
Ringtone r = RingtoneManager.getRingtone(getApplicationContext(), notification);
r.play();
} catch (Exception e) {
e.printStackTrace();
}
}
//Called when service is no longer be available .
#Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
Log.d("GCMNotificationIntentService", "GCMNotificationIntentService Destroyed");
}
}
According to the new documentation which was updated on October 2, 2018 you must send post request as below
https://fcm.googleapis.com/fcm/send
Content-Type:application/json
Authorization:key=AIzaSyZ-1u...0GBYzPu7Udno5aA //Server key
{
"to": "sent device's registration token",
"data": {
"hello": "message from someone",
}
}
To get device's registration token extend FirebaseMessagingService and override onNewToken(String token)
For more info refer to doc https://firebase.google.com/docs/cloud-messaging/android/device-group
I am late but above solutions has helped me to write down this simple answer, you can send your message directly to android devices from android application, here is the simple implementation I have done and it works great for me.
compile android volley library
compile 'com.android.volley:volley:1.0.0'
Just copy paste this simple function ;) and your life will become smooth just like knife in butter. :D
public static void sendPushToSingleInstance(final Context activity, final HashMap dataValue /*your data from the activity*/, final String instanceIdToken /*firebase instance token you will find in documentation that how to get this*/ ) {
final String url = "https://fcm.googleapis.com/fcm/send";
StringRequest myReq = new StringRequest(Request.Method.POST,url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
Toast.makeText(activity, "Bingo Success", Toast.LENGTH_SHORT).show();
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(activity, "Oops error", Toast.LENGTH_SHORT).show();
}
}) {
#Override
public byte[] getBody() throws com.android.volley.AuthFailureError {
Map<String, Object> rawParameters = new Hashtable();
rawParameters.put("data", new JSONObject(dataValue));
rawParameters.put("to", instanceIdToken);
return new JSONObject(rawParameters).toString().getBytes();
};
public String getBodyContentType()
{
return "application/json; charset=utf-8";
}
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
HashMap<String, String> headers = new HashMap<String, String>();
headers.put("Authorization", "key="+YOUR_LEGACY_SERVER_KEY_FROM_FIREBASE_CONSOLE);
headers.put("Content-Type","application/json");
return headers;
}
};
Volley.newRequestQueue(activity).add(myReq);
}
Note
If you want to send message to topics so you can change parameter instanceIdToken to something like /topics/topicName.
For groups implementation is the same but you just need to take care of parameters. checkout Firebase documentation and you can pass those parameters.
let me know if you face any issue.
I'm using firebase anonymous authantication for my unity project.
As i always did when project is started i'm sending request to firebase for authantication,
but on my last project (which uses firebase sdk 6.16.0) my request creates new user everytime.
Here is some code about how i'm sending my request
Firebase.Auth.FirebaseAuth auth = Firebase.Auth.FirebaseAuth.DefaultInstance;
auth.SignInAnonymouslyAsync().ContinueWith((task =>
{
if (task.IsCanceled)
{
Debug.Log("task cancelled");
return;
}
if (task.IsFaulted)
{
Debug.Log("task cancelled");
return;
}
if (task.IsCompleted)
{
Firebase.Auth.FirebaseUser userr = task.Result;
firebaseUserId = userr.UserId;
Debug.Log("firebaseUserId");
Debug.Log(firebaseUserId);
//every opening returns new uniq id here.
}
}));
On firebase authantication panel i only activated anonymous login. any suggestions?
Or is there any way to downgrade unity firebase version? i've tried to import old version which i was using on my last game (sdk 6.15.2) but there is some errors on resolver.
Basically, every time you call SignInAnonymouslyAsync you'll create a new user and the last one will be basically lost (it's more or less a random hash - anonymous as it's name suggests).
I'll typically do something like:
using System;
using Firebase.Auth;
using UnityEngine;
using UnityEngine.Events;
public class Login : MonoBehaviour
{
public UnityEvent OnSignInFailed = new UnityEvent();
public UserSignedInEvent OnUserSignedIn = new UserSignedInEvent();
public async void TriggerLogin()
{
var auth = FirebaseAuth.DefaultInstance;
var user = auth.CurrentUser;
if (user == null)
{
try
{
user = await auth.SignInAnonymouslyAsync();
}
catch (Exception e)
{
Debug.LogException(e);
OnSignInFailed.Invoke();
return;
}
}
// user definitely should not be null!
if (user == null)
{
OnSignInFailed.Invoke();
Debug.LogWarning("User still null!?");
return;
}
var userName = user.UserId;
OnUserSignedIn.Invoke(userName);
Debug.Log($"Logged in as {userName}");
}
[Serializable]
public class UserSignedInEvent : UnityEvent<string>
{
}
}
Note that for this code snippet, TriggerLogin is a public method so I can chain it off of a UnityEvent in the Unity editor.
Try and Put it some kind of check to find if used is already logged in. If yes, then do a silent login, if no then use anonymous login.
Currently you are straightaway logging in user even if they logged in last time they opened the Application.
Try this link: https://github.com/firebase/quickstart-unity/issues/266#issuecomment-447981995
I am trying the sign in a user with the silent signin api.
First time a user opens the app iam singin in the user using Auth.GoogleSignInApi.getSignInResultFromIntent(data); where the user is prompted to choose a signin email.
Next time a need a renewed token, i try to get a token in the background, by using the Auth.GoogleSignInApi.silentSignIn(mGoogleApiClient);
code is as follows:
public void createNewToken(String serverKey, Context context) {
this.context = context;
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(serverKey)
.requestEmail()
.requestProfile()
.build();
GoogleApiClient mGoogleApiClient = new GoogleApiClient.Builder(context)
.addOnConnectionFailedListener(this)
.addApi(Auth.GOOGLE_SIGN_IN_API, gso)
.addScope(new Scope(Scopes.PROFILE))
.addScope(new Scope(Scopes.EMAIL))
.build();
OptionalPendingResult<GoogleSignInResult> pendingResult = Auth.GoogleSignInApi.silentSignIn(mGoogleApiClient);
if (pendingResult.isDone()) {
handleResult(pendingResult.get());
} else {
pendingResult.setResultCallback(new ResultCallback<GoogleSignInResult>() {
#Override
public void onResult(#NonNull GoogleSignInResult result) {
handleResult(result);
}
});
}
}
However, the problem is i dont get any callback, either from isDone or in the callback(). no error are given except from this:
D/GoogleSignInApiImpl: getSavedSignInResultIfEligible
D/GoogleSignInApiImpl: trySilentSignIn
Am i dusing the api wrongly or why dosnt this work? thx for any feedback!
Try adding ".enableAutoManage(...)" when building the Google API client: developers.google.com/identity/sign-in/android
If you don't want to use enableAutoManage, because you are not in a FragmentActivity for example, you can call manually googleApiClient.connect() and disconnect.
I want to create a user with a role in the same transaction but i have an issue with the implementation. In order to use the userStore in the transaction and have it not save the changes automatically and ignore my transaction i had to turn off AutoSaveChanges. This makes it so it will wait until i call save changes. This works fine but because the userstore now does not return the userId when i call manager.Create due to this being off I dont have an Id to pass into userManager.AddToRole. Is there any way to add the user i am trying to create to a role within the same transaction?
If you start your transaction manually, then commit it, everything that was written to DB inside your transaction will be held inside your transaction. And you can rollback that if you want to.
Do something like that:
var dbContext = // get instance of your ApplicationDbContext
var userManager = // get instance of your ApplicationUserManager
using (var transaction = dbContext.Database.BeginTransaction(IsolationLevel.ReadCommitted))
{
try
{
var user = // crate your ApplicationUser
var userCreateResult = await userManger.CreateAsync(user, password);
if(!userCreateResult.Succeeded)
{
// list of errors in userCreateResult.Errors
transaction.Rollback();
return userCreateResult.Errors;
}
// new Guid for user now saved to user.Id property
var userId = user.Id;
var addToRoleresult = await userManager.AddToRoleAsync(user.Id, "My Role Name");
if(!addToRoleresult.Succeeded)
{
// deal with errors
transaction.Rollback();
return addToRoleresult.Errors;
}
// if we got here, everything worked fine, commit transaction
transaction.Commit();
}
catch (Exception exception)
{
transaction.Rollback();
// log your exception
throw;
}
}
Hope this helps.