We Keep Coding

Data Retrieval from Firestore is erratic

I'm working on an Android app that does the following:
Upon app start-up, it checks if a user is logged in, using AuthStateListener.
If there is a user logged in, it retrieves data from Firestore. The user data is stored in a document that I named with the following nomenclature: "User " + user's_email_ID. For example, if a user has an email ID xyz#gmail.com, his data will be stored in the document named: User xyz#gmail.com.
All documents are within the collection named "Users".
If all the fields are null/ empty in the user's data document, the app opens an Activity that asks him/her to fill all the details. Else, it takes the user to the main page (StudentMainActivity if the user is a student, or ProfessorMainActivity if the user is a professor).
Coming to my problem:
The block of code which checks whether the fields are empty has some erratic and unpredictable behavior. I'm not sure if this is a problem based on Firestore, or on the fact that data retrieval happens on a different thread.
I checked the Firestore database and saw that all fields were filled. However, when a user (who's already logged in) starts the app, the app knows that it is the same user (i.e. he's not prompted to sign in, because AuthStateListener does its job), but instead of being redirected to either StudentMainActivity or ProfessorMainActivity (the main screens), he's asked to fill his details again.
What's more confusing is that this bug doesn't always occur. There are times when the app does what is expected, i.e. take the user to the main screen, but the next time he starts the app, he's again taken to the activity that asks him to enter his details.
Source Code:
LoginActivity.java (Only the relevant parts)
//AuthStateListener is in onCreate
authStateListener = new FirebaseAuth.AuthStateListener() {
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth firebaseAuth) {
FirebaseUser user = firebaseAuth.getCurrentUser();
if (user != null){
UIDEmailID = user.getEmail();
updateUI(user);
}
else{
updateUI(null);
}
}
};
private void updateUI(FirebaseUser user){
// Update UI after login
if (user != null) {
Toast.makeText(LoginActivity.this, "User " + UIDEmailID, Toast.LENGTH_LONG).show();
db.collection("Users").document("User " + UIDEmailID).get()
.addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
#Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
if (documentSnapshot.get("department") != null || // if any
documentSnapshot.get("phoneNumber") != null || // field in
documentSnapshot.get("name") != null || // Firestore is
documentSnapshot.get("studentSemester") != null || // non-null then
documentSnapshot.get("dateOfBirth") != null || // proceed to
documentSnapshot.get("university") != null) { // further activities
if (documentSnapshot.get("userType") == "Lecturer/ Professor") {
Intent intent = new Intent(LoginActivity.this, ProfessorMainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
else {
Intent intent = new Intent(LoginActivity.this, StudentMainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
} else {
Toast.makeText(LoginActivity.this, "We need some additional details before we go ahead.", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(LoginActivity.this, GFBDetailsActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
}
}).addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Toast.makeText(LoginActivity.this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
});
}
}
I'm sorry for the long question; I just tried to make it super descriptive. Some help would be greatly appreciated.
P.S. The reason I think this is a problem involving the usage of multiple threads is because whenever the app runs as expected (i.e. takes the user to the main screen), the toast "We need some additional details before we go ahead." appears as well. If you look at the code (the last "else" block) you will realise that it is in a seperate conditional block altogether, and thus isn't even supposed to show up if the main screen (which is in another conditional block) shows up.
EDIT 1:
I'm enclosing screenshots pertaining to the problem. Ignore the bland UI :P
This is what's expected (Comes under the second 'else' block). It is supposed to show up only if the user is logging in for the first time, i.e. does not have his data stored in a Firestore document.
The background is StudentMainActivity (inside the nested 'else'). However, even the Toast is displayed (it belongs to a seperate block altogether).

So it turns out Firestore wasn't (entirely) at fault.
Every activity in an Android application has a life span, and every time an activity is run, it goes through an elaborate sequence of lifecycle functions.
An activity's lifecycle is as follows:
Launched --> onCreate() --> onStart() --> onResume() --> Running --> onPause() --> onStop() --> onDestroy() --> Finished
I won't be digressing by going into the details of each function, because the function names are quite intuitive and self-explanatory.
As you can see in the code snippet in the question, onAuthStateChanged() is inside onCreate(). My Document ID on Firebase is of the form "User UIDEmailID", where UIDEmailID is the email ID of the user. And UIDEmailID gets updated only in onAuthStateChanged() (which, in turn, is inside onCreate()), i.e. only when the activity starts afresh, after the app has been closed and opened again.
Therefore, I updated UIDEmailID in onStart() as well, which means that every time an app is resumed, it will retrieve the email ID of the user, which can subsequently be used to retrieve the document from Firestore.
Also, I slightly tweaked my Firestore data retrieval bit of code upon advice from Nibrass H. The solution is as follows:
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
running = true;
if (savedInstanceState != null){
running = savedInstanceState.getBoolean("running");
wasrunning = savedInstanceState.getBoolean("wasrunning");
}
setContentView(R.layout.splash_screen);
firebaseAuth = FirebaseAuth.getInstance();
db = FirebaseFirestore.getInstance();
authStateListener = new FirebaseAuth.AuthStateListener() {
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth firebaseAuth1) {
FirebaseUser user = firebaseAuth1.getCurrentUser();
if (user != null){
UIDEmailID = user.getEmail();
updateUI(user);
} else {
updateUI(null);
}
}
};
}
#Override
protected void onStart() {
super.onStart();
firebaseAuth.addAuthStateListener(authStateListener);
if (firebaseAuth.getCurrentUser() != null) {
UIDEmailID = firebaseAuth.getCurrentUser().getEmail();
updateUI(firebaseAuth.getCurrentUser());
} else {
updateUI(null);
}
}
#Override
protected void onRestart() {
super.onRestart();
authStateListener = new FirebaseAuth.AuthStateListener() {
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth firebaseAuth1) {
FirebaseUser user = firebaseAuth1.getCurrentUser();
if (user != null) {
UIDEmailID = user.getEmail();
updateUI(user);
} else {
updateUI(null);
}
}
};
}
#Override
protected void onPause() {
super.onPause();
wasrunning = running;
running = false;
}
#Override
protected void onResume() {
super.onResume();
if (wasrunning){
running = true;
}
}
#Override
protected void onStop() {
super.onStop();
if (authStateListener != null) {
firebaseAuth.removeAuthStateListener(authStateListener);
}
}
private void updateUI(FirebaseUser firebaseUser){
if (firebaseUser != null){
Toast.makeText(this, "User " + firebaseUser.getEmail(), Toast.LENGTH_SHORT).show();
db.collection("Users").document("User " + UIDEmailID).get()
.addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
#Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
if (documentSnapshot.get("userType") != null) {
if (documentSnapshot.get("userType").equals("Lecturer/ Professor")){
Intent intent = new Intent(SplashScreenActivity.this, ProfessorMainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
finish();
startActivity(intent);
} else {
Intent intent = new Intent(SplashScreenActivity.this, StudentMainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
finish();
startActivity(intent);
}
} else {
Toast.makeText(SplashScreenActivity.this, "We need some additional details before we go ahead.", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(SplashScreenActivity.this, GFBDetailsActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
finish();
startActivity(intent);
}
}
});
}
}

Connect userId with a unique photo in Firebase

I have an app where it is possible to create an user and this work perfectly and I am happy!
In a simple way, here is a method that adds the user to the Firebase database:
public void addUserInfoToDatabase(){
String user_id = mAuth.getCurrentUser().getUid();
final DatabaseReference the_user_database = FirebaseDatabase.getInstance().getReference().child("UserRegistraion").child(user_id);
Map userAttributes = new HashMap();
userAttributes.put("user_id", user_id);
userAttributes.put("username", userName);
userAttributes.put("name", name);
userAttributes.put("e-mail", email);
the_user_database.setValue(userAttributes);
if (mRegistrationListener != null)
mRegistrationListener.onRegistrationComplete(true); // Assumes success
}
And here is how the table looks when the user is registered:
What I want to do now is that I want the possibility to add a profile picture which belongs to each user: e,g a profile picture, family-picture etc.
The question is: how can i do this in Firebase? I am not asking anyone to do this for me, but just to give me a good tip or provide a guide/video for how to do this.
Thank you.

I usually create a separate activity for setting up a profile photo. Maybe instead of calling onRegistrationComplete call an onCompleteListener after setValue(userAttributes) like this:
the_user_database.setValue(userAttributes).addOnCompleteListener(new OnCompleteListener...){
Intent intent = new Intent(context, AddProfileActivity.class);
startActivity(intent);
In the next activity it could be a simple XML layout with a button and an ImageView.
This code can open your gallery, select an image, and place it in your imageview in the onActivityResult method:
private void selectPhotoFromGallery(){
Log.d(TAG, "selectPhotoFromGallery: started");
Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(intent, GALLERY_PICK);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, #Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == GALLERY_PICK){
if (resultCode == RESULT_OK && data != null){
contentUri = data.getData();
try{
Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), contentUri);
profile_photo.setImageBitmap(bitmap);
}catch (IOException e){
Toast.makeText(mContext, e.getMessage(), Toast.LENGTH_LONG).show();
}
}
}
}
You would then need a method to upload your image to FirebaseStorage and capture the downloadUrl to add to the desired node. In this case because you are adding to an existing node you call updateChildren() when adding the profile photo. I use a method like this:
private void uploadProfileImage(){
Log.d(TAG, "uploadProfileImage: uploading image....");
if (contentUri != null){
//from gallery
final StorageReference reference = FirebaseStorage.getInstance().getReference().child(currentUserID).child("profile_photo");
reference.putFile(contentUri).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
#Override
public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
reference.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
#Override
public void onSuccess(Uri uri) {
String profilePhotoUri = uri.toString();
DatabaseReference publicUserReference = FirebaseDatabase.getInstance().getReference().child("public_user")
.child(currentUserID);
HashMap hashMap = new HashMap();
hashMap.put("profile_photo", profilePhotoUri);
publicUserReference.updateChildren(hashMap).addOnCompleteListener(new OnCompleteListener() {
#Override
public void onComplete(#NonNull Task task) {
if (task.isSuccessful()){
Intent intent = new Intent(mContext, CompleteProfileActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finish();
}
}
});
}
});
}
});
}
}
You would need to adjust this for your specific needs obviously. The thing you are really trying to do is to save an image to Storage and get the http://... string location where it is stored and then insert that information into the same location as the previous information you provided.
I hope this counts as a helpful tip. https://www.youtube.com/watch?v=mPOhnTnLcSY That's a link to a video about uploading images to Firebase storage for more information if you need it. Good luck!

Android Studio: 2 different activities in 1 button

I want to make the login button to dispatch into 2 different activities using the flag column on the database??
if the tenant logged in it will redirect to the tenant activity
and when the landlord is logged in it will redirect to the other activity?
public void onResponse(String response) {
Log.e(TAG, "Register Response: " + response.toString());
hideDialog();
try {
JSONObject jObj = new JSONObject(response);
success = jObj.getInt(TAG_SUCCESS);
// Check for error node in json
if (success == 1) {
String username = jObj.getString(TAG_USERNAME);
String id = jObj.getString(TAG_ID);
Log.e("Successfully Login!", jObj.toString());
Toast.makeText(getApplicationContext(), jObj.getString(TAG_MESSAGE), Toast.LENGTH_LONG).show();
SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putBoolean(session_status, true);
editor.putString(TAG_ID, id);
editor.putString(TAG_USERNAME, username);
editor.commit();
// go to main activity
Intent intent = new Intent(LoginActivity.this, MainActivity.class);
intent.putExtra(TAG_ID, id);
intent.putExtra(TAG_USERNAME, username);
finish();
startActivity(intent);
} else {
Toast.makeText(getApplicationContext(),
jObj.getString(TAG_MESSAGE), Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
}
}

Inside the onClickListener() method of your log in button,you can put a if() statement.
Steps To Do this
1. Get the data from the username and password field and use that in your query to retrieve the data from the database
2. Store the data you retrieved in a String like below because you will get only one row:
String flag = cursor.getString(7); //skipping the cursor and other database part
3. Now you can put the if() statement in the onClickListener of login button after getting the String flag value like:
if(flag.equals(landlord)){
Intent intent = new Intent(this,Landlord.class);
startActivity(intent);
}
else{
Intent intent = new Intent(this,Tenant.class);
startActivity(intent);
}

Anyhow you will be querying to verify username & password, at the same time you could also fetch the flag information and store it in locally(reduces the database calls).
Store those data in a map with key as username (Assumption username will be unique) and flag as value.
Map<String,String> mapToRouting = new Map<String,String>();
Now for routing different activities, inside the button click method try like
public static void buttonClickMethod(){
//textFieldUserName is the username of user trying to login
if(isLanlord(textFieldUserName)){
//this means user is Landlord & put code to redirect to corresponding screen
}
else{
//put code to which redirects to tenants screen!
}
}
Method to find whether the user is landlor or not.
public static void isLandlord(String userName){
boolean result = false;
if(mapToRouting.get(userName).equalsIgnorecase("Landlord"))
result = true;
return result;
}
Hope this will be helpful.

Sending messages to multiple contacts using Intent

I'm trying to send messages through in built sms app through Intent. Its working fine. Here is my code
public class Main_Act extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button startBtn = (Button) findViewById(R.id.button);
startBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
if(sendSMS()) {
Intent intent = new Intent(Main_Act.this, Sample.class);
startActivity(intent);
}
}
});
}
protected boolean sendSMS() {
ArrayList<String> nums = new ArrayList<String>();
nums.add("111111111");
nums.add("222222222");
Log.i("Send SMS", "");
Intent smsIntent = new Intent(Intent.ACTION_VIEW);
smsIntent.setData(Uri.parse("smsto:"));
smsIntent.setType("vnd.android-dir/mms-sms");
smsIntent.putExtra("address" ,nums);
smsIntent.putExtra("sms_body" , "Test ");
try {
startActivity(smsIntent);
finish();
return true;
}
catch (android.content.ActivityNotFoundException ex) {
Toast.makeText(Main_Act.this,
"SMS faild, please try again later.", Toast.LENGTH_SHORT).show();
return false;
}
}
}
But the problem is it gets navigated to another activity without clicking send button in sms application. It should goto another activity only after clicking the send button in messaging app. Can anyone help me with this problem, Thanks in advance.

Let's clear out a slight misunderstanding in your code:
You should not try to start both intents in the same part/run of the code as you do here.
A startActivity will not execute directly going to the activity and then return to the same place in the code when activity execution finishes. In stead it asynchronously queues the intent for execution. Then your code queues another intent for execution. After the current code finishes (in this case when the button onClick() method ends) Android queue mgmt can start picking off the queue. Probably the first intent is executed shortly and then directly overrun by an immediate execution of the second.
So what happens in summary is that you first add one intent to the queue in sendSMS and then add intent 2 to the queue in onClick, before leaving. Now both the intents are executed.
What you need to do is to change the sendSMS code to something like:
Intent smsIntent = new Intent(Intent.ACTION_VIEW);
smsIntent.setData(Uri.parse("smsto:"));
smsIntent.setType("vnd.android-dir/mms-sms");
smsIntent.putExtra("address" ,nums);
smsIntent.putExtra("sms_body" , "Test ");
// To force the SMS app to return immediately after sent SMS
smsIntent.putExtra("exit_on_sent", true);
startActivityForResult(smsIntent, MY_SMS_REQUEST_RESPONSE_CODE);
Note the startActivityForResult() method that indicates that we expect Android to return and the "exit_on_sent" extra, to force a swift return.
MY_SMS_REQUEST_RESPONSE_CODE is just any random code you select to recognize the returning result in the callback method (even if you currently do not expect any other returning results, you may have some in the future).
Next thing to do is to remove the second intent creation and queuing. In stead you implement the following callback method (added to this activity):
#Override
protected void onActivityResult(
int callbackIdentifier, int resultCode, Intent intent) {
// Is this the expected sendSMS callback ?
if (callbackIdentifier== MY_SMS_REQUEST_RESPONSE_CODE) {
if (resultCode == RESULT_OK) {
// Continue where you left off (e.g. execute intent 2)
Intent intent = new Intent(Main_Act.this, Sample.class);
startActivity(intent);
} else if (resultCode == RESULT_CANCELED) {
// Error handling/retrying etc
}
}
// Support inherited callback functions
super.onActivityResult(callbackIdentifier,resultCode,intent);
}

Note: if you want to pass data and type don't call method separately because will delete each other you must pass it in one method
wrong
smsIntent.setData(Uri.parse("smsto:"));
smsIntent.setType("vnd.android-dir/mms-sms");
true
smsIntent.setDataAndType(Uri.parse("smsto:"),"vnd.android-dir/mms-sms");

IntentService does not get started

I'm making an android application which uses it's own Camera activity. The images are then stored on the local SQLite database by using an IntentService.
Problem now is: the IntentService doesn't get started after the picture is taken. When using this IntentService on other occations it works perfect so I am at a loss on the why it is not working...
Below is the code used in my CameraActivity to take a picture and start the IntentService.
mPicture = getPictureCallback();
mRaw = getRawCallback();
mShutter = getShutterCallback();
mCamera.takePicture(mShutter, mRaw, mPicture);
private PictureCallback getPictureCallback() {
PictureCallback picture = new PictureCallback() {
#Override
public void onPictureTaken(byte[] data, Camera camera) {
Log.d(LOG_TAG, "Picture taken, starting service");
Intent databaseIntent = new Intent(MyCameraActivity.this, DBHandlerService.class);
databaseIntent.putExtra("image", data);
databaseIntent.putExtra("action", "save");
databaseIntent.putExtra(AppConstant.RESULT_RECEIVER, mReceiver);
startService(databaseIntent);
mPreview.refreshCamera(mCamera);
}
};
return picture;
}
The onHandleEvent:
#Override
protected void onHandleIntent(Intent intent) {
Log.d(LOG_TAG, "onHandle started");
Database db = getDB();
action = intent.getStringExtra("action");
Bundle resultbundle = new Bundle();
Log.d(LOG_TAG, "onHandleIntent action : " + action);
final ResultReceiver reciever = intent
.getParcelableExtra(AppConstant.RESULT_RECEIVER);
reciever.send(STATUS_RUNNING, Bundle.EMPTY);
//Different actions depending on the "action" string
if(action.equals("xxxxx"){
//perform action
} else {
// inform activity the requested action does not exist. When
// STATUS_ERROR is received they must check if errorcode is not
// null.
resultbundle.putString("errormsg", "No actions undertaken");
resultbundle.putInt("errorcode", 9999);
reciever.send(STATUS_ERROR, resultbundle);
}
}
I also use this IntentService to get all the pictures from the database. Since the DB stays empty no images are returned but every log gets printed.
If i try it to save the image the logs inside the IntentService are nevr printed.
If more code is needed, let me know.
Thanks in advance!
Thomas