When running the app the data is not retrieved but when debugging i can see where it is in terms of the database link.
When it runs and get to addValueEventListener, it doesn't go into the function which is pretty weird, don't know if this is because its async or not but either way data from Firebase does not get retrieved.
public GarbageItems(int itemNum) {
String itemId = String.valueOf(itemNum);
database = FirebaseDatabase.getInstance();
gameObjectRef = database.getReference().child("gameObjects");
itemInformationGrabber(gameObjectRef, itemId);
}//GarbageItems(Constructor)
private void itemInformationGrabber(DatabaseReference gameObjectRef, String itemId) {
DatabaseReference dataReference = gameObjectRef.child(itemId);
DatabaseReference itemColor = dataReference.child("Color");
itemColor.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange( DataSnapshot dataSnapshot) {
String color = dataSnapshot.getValue(String.class);
setColor(color);
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
This is in a different classs that calls GarbageItem
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_game);
colorTextView = findViewById(R.id.ColorTextView);
itemTextView = findViewById(R.id.ItemNameTextView);
GarbageItems garbageItems = new GarbageItems(1);
Color = garbageItems.getColor();
}
try this...
private void itemInformationGrabber(DatabaseReference gameObjectRef, String itemId) {
DatabaseReference dataReference = gameObjectRef.child(itemId);
DatabaseReference itemColor = dataReference.child("Color");
itemColor.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange( DataSnapshot dataSnapshot) {
for(Datasnapshot dataSnap : dataSnapshot.getChildren()){
String color = dataSnap.child("Color").getValue(String.class);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
Hope it helps you :)
Related
I'm new to the firebase and android studio. I'm working on a project in which I have to fetch details of the current user and display the name. It is throwing "user doesn't exist' toast even if I'm logged in I'm attaching everything below. Maybe I have done some mistakes please let me know.
Code to fetch details of the current user
public class Succesfully_sign_up extends AppCompatActivity {
DatabaseReference reff;
TextView name;
Button signout;
FirebaseUser curr_user;
String curr_user_str;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_succesfully_sign_up);
name = findViewById(R.id.name);
curr_user=FirebaseAuth.getInstance().getCurrentUser();
if(curr_user!=null)
{
curr_user_str = curr_user.getUid();
reff = FirebaseDatabase.getInstance().getReference("userdetails");
reff.child(curr_user_str).addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
HelperClass data = dataSnapshot.getValue(HelperClass.class);
if (data != null) {
name.setText(data.getFullname_hc());
} else {
Toast.makeText(Succesfully_sign_up.this, "User does't exist", Toast.LENGTH_SHORT).show();
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
else
{
startActivity(new Intent(Succesfully_sign_up.this,student_signup.class));
}
}
}
My HelperClass
public class HelperClass {
String fullname_hc,amizone_id_hc,mobile_num_hc,email_id_hc;
public HelperClass()
{
}
public HelperClass(String fullname_hc, String amizone_id_hc, String mobile_num_hc, String email_id_hc) {
this.fullname_hc = fullname_hc;
this.amizone_id_hc = amizone_id_hc;
this.mobile_num_hc = mobile_num_hc;
this.email_id_hc = email_id_hc;
}
public String getFullname_hc() {
return fullname_hc;
}
public void setFullname_hc(String fullname_hc) {
this.fullname_hc = fullname_hc;
}
public String getAmizone_id_hc() {
return amizone_id_hc;
}
public void setAmizone_id_hc(String amizone_id_hc) {
this.amizone_id_hc = amizone_id_hc;
}
public String getMobile_num_hc() {
return mobile_num_hc;
}
public void setMobile_num_hc(String mobile_num_hc) {
this.mobile_num_hc = mobile_num_hc;
}
public String getEmail_id_hc() {
return email_id_hc;
}
public void setEmail_id_hc(String email_id_hc) {
this.email_id_hc = email_id_hc;
}
}
I think you have created the database manually, your user id 8448.... is not generated by the Firebase android, so it is showing that error. If not then please share the code of creation of that above database structure.
How about looping through the children and accessing data:
//the reference
reff = FirebaseDatabase.getInstance().getReference("userdetails");
//the reading
reff.child.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
//loop through every possible child under "userdetails"
for(DataSnapshot ds : dataSnapshot.getChildren()){
String fullName = ds.child("fullname_hc").getValue(String.class);
name.setText(fullName);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
I am currently working on a chat application and have come across an issue. My Chat Fragment contains my Recyclerview which populates data from Firebase DB. I am able to obtain the data, but I am running into an issue. When I open my Chat Activity and send a message, a new push id is created with the information stored in the child. The data obtained by my recyclerview is it gets the last push id and retrieves the last message that was sent. The problem is, when I go back into my fragment, the recyclerview re-populates and adds the new push id last message that was created, and creates another item instead of just refreshing the original item.
So essentially, I will load my app, go into the Chat Fragment, my recyclerview will display the other user and the last message that was sent, no problem, then I will click on that item, open the chat activity, send a message then go back. Now when I am back into the chat fragment I will have two or three or however many messages that were sent displaying in the recyclerview. Not sure on how to fix this, my code is below:
DATABASE STRUCTURE
Chat Fragment
public class Fragment_MatchChats extends Fragment {
private RecyclerView mRecyclerView, mRecyclerViewChat;
private RecyclerView.Adapter mMatchesAdapter, mChatAdapter;
private String currentUserID;
private DatabaseReference mDatabaseChat;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.frag_match_chat, container, false);
currentUserID = FirebaseAuth.getInstance().getCurrentUser().getUid();
mDatabaseChat = FirebaseDatabase.getInstance().getReference().child("Chat");
LinearLayoutManager layoutManagerChat = new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false);
mRecyclerViewChat = (RecyclerView) v.findViewById(R.id.recyclerViewChat);
mRecyclerViewChat.setHasFixedSize(true);
mRecyclerViewChat.setLayoutManager(layoutManagerChat);
mChatAdapter = new RecyclerViewChatAdapter(getDataSetChat(), getContext());
getUserMatchId();
return v;
}
//this method will get the user ID in the database that you matched with. It will run through the matches child and get all the user IDs
private void getUserMatchId() {
DatabaseReference matchDB = FirebaseDatabase.getInstance().getReference().child("Users").child(currentUserID).child("swipes").child("matches");
matchDB.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (dataSnapshot.exists()){
for(DataSnapshot match : dataSnapshot.getChildren()){
CheckChatID(match.getKey());
}
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
private void CheckChatID(final String chat) {
DatabaseReference ChatDB = FirebaseDatabase.getInstance().getReference().child("Users").child(currentUserID).child("swipes").child("matches")
.child(chat).child("ChatID");
ChatDB.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (dataSnapshot.exists()){
String ChatID = dataSnapshot.getValue().toString();
ChatIDExist(ChatID, chat);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
private void ChatIDExist(final String chatID, final String oppUserID) {
final DatabaseReference ChatDB = mDatabaseChat.child(chatID);
final Query lastQuery = ChatDB.orderByKey().limitToLast(1);
ChatDB.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (dataSnapshot.exists()){
lastQuery.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot child: dataSnapshot.getChildren()){
String key = child.child("text").getValue().toString();
FetchChatInfo(oppUserID,key);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
private void FetchChatInfo(String key, final String chatID) {
DatabaseReference userDB = FirebaseDatabase.getInstance().getReference().child("Users").child(key);
userDB.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if(dataSnapshot.exists()){
String matched_userID = dataSnapshot.getKey();
String matches_userName = "";
String matches_userProPic = "";
String match_CHATID = chatID;
if(dataSnapshot.child("name").getValue() != null){
matches_userName = dataSnapshot.child("name").getValue().toString();
}
if(dataSnapshot.child("profilePicURL").getValue() != null){
matches_userProPic = dataSnapshot.child("profilePicURL").getValue().toString();
}
RecyclerViewChatReference chat_obj = new RecyclerViewChatReference(matched_userID, matches_userName, matches_userProPic, match_CHATID);
resultsChats.add(chat_obj);
mRecyclerViewChat.setAdapter(mChatAdapter);
mChatAdapter.notifyDataSetChanged();
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
private ArrayList<RecyclerViewChatReference> resultsChats = new ArrayList<RecyclerViewChatReference>();
private List<RecyclerViewChatReference> getDataSetChat() {
return resultsChats;
}
Chat Activity
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_chat);
matchId = getIntent().getExtras().getString("matchID");
currentUserID = FirebaseAuth.getInstance().getCurrentUser().getUid();
mDatabaseUser = FirebaseDatabase.getInstance().getReference().child("Users").child(currentUserID)
.child("swipes").child("matches").child(matchId).child("ChatID");
mDatabaseChat = FirebaseDatabase.getInstance().getReference().child("Chat");
getChatId();
mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
mRecyclerView.setNestedScrollingEnabled(false);
mRecyclerView.setHasFixedSize(false);
mChatLayoutManager = new LinearLayoutManager(ChatActivity.this);
mRecyclerView.setLayoutManager(mChatLayoutManager);
mChatAdapter = new ChatAdapter(getDataSetChat(), ChatActivity.this);
mRecyclerView.setAdapter(mChatAdapter);
mSendEditText = findViewById(R.id.message);
mSendButton = findViewById(R.id.send);
mSendButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
sendMessage();
}
});
}
private void sendMessage() {
String sendMessageText = mSendEditText.getText().toString();
if(!sendMessageText.isEmpty()){
DatabaseReference newMessageDb = mDatabaseChat.push();
Map newMessage = new HashMap();
newMessage.put("createdByUser", currentUserID);
newMessage.put("text", sendMessageText);
newMessageDb.setValue(newMessage);
}
mSendEditText.setText(null);
}
private void getChatId(){
mDatabaseUser.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (dataSnapshot.exists()){
chatId = dataSnapshot.getValue().toString();
mDatabaseChat = mDatabaseChat.child(chatId);
getChatMessages();
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
private void getChatMessages() {
mDatabaseChat.addChildEventListener(new ChildEventListener() {
#Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
if(dataSnapshot.exists()){
String message = "";
String createdByUser = "";
if(dataSnapshot.child("text").getValue()!=null){
message = dataSnapshot.child("text").getValue().toString();
}
if(dataSnapshot.child("createdByUser").getValue()!=null){
createdByUser = dataSnapshot.child("createdByUser").getValue().toString();
}
if(message!=null && createdByUser!=null){
Boolean currentUserBoolean = false;
if(createdByUser.equals(currentUserID)){
currentUserBoolean = true;
}
ChatObject newMessage = new ChatObject(message, currentUserBoolean);
resultsChat.add(newMessage);
mChatAdapter.notifyDataSetChanged();
}
}
}
#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(DatabaseError databaseError) {
}
});
}
private ArrayList<ChatObject> resultsChat = new ArrayList<ChatObject>();
private List<ChatObject> getDataSetChat() {
return resultsChat;
}
}
I was trying to retrieve the data from user and time. But I can't access the data, it's not really accessing the database.
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_balance);
mFirebaseDatabase=FirebaseDatabase.getInstance();
cashRef=mFirebaseDatabase.getReference().child("ASSETS").child("cash_at_bank");
TextView view=(TextView)findViewById(R.id.view);
view.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
cashRef.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
int time=dataSnapshot.getValue(int.class);
int values =dataSnapshot.getValue(int.class);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
});
To get the time, please use the following code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference cashAtBankRef = rootRef.child("ASSETS").child("Cash at bank");
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
Long time = ds.child("time").child("time").getValue(Long.class);
Log.d("TAG", time + "");
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
cashAtBankRef.addListenerForSingleValueEvent(eventListener);
The output will be:
150555043995
//and so on
I have data in database:
database in firebase
I want read all child (Belgia, Czechy, Polska...) and display it in Text Field, but AFTER click the button (I don't change data in database).
The button have assigned below function:
public void f_btn_zaczytaj_dane(View view) {
myRef.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String value = dataSnapshot.getValue(String.class);
TextView txt_opis_panstwa = (TextView) findViewById(R.id.txt_opis_panstwa);
txt_opis_panstwa.setText(value);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
Befrore i write in code:
FirebaseDatabase database;
DatabaseReference myRef;
database = FirebaseDatabase.getInstance();
myRef = database.getReference("kraj");
Unfortunately, when I press the button nothing happens.
I will be grateful for the help
Regards, Marcin
You have to iterate through your children
public void f_btn_zaczytaj_dane(View view) {
myRef.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
TextView txt_opis_panstwa = (TextView) findViewById(R.id.txt_opis_panstwa);
for (DataSnapshot country : dataSnapshot.getChildren()) {
txt_opis_panstwa.append(country.getKey());
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
Please use this code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference krajRef = rootRef.child("flagiistolice").child("kraj");
public void f_btn_zaczytaj_dane(View view) {
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
TextView txt_opis_panstwa = (TextView) findViewById(R.id.txt_opis_panstwa);
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String country = ds.getkey();
txt_opis_panstwa.append(country);
Log.d("TAG", country);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
krajRef.addListenerForSingleValueEvent(eventListener);
}
This is my DisplayBooks class:
public class DisplayBooks extends AppCompatActivity
private FirebaseAuth myAuth;
private DatabaseReference myDatabase;
private TextView book1display,book2display,book3display,book4display,book5display,book6display,book7display;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_books);
myAuth = FirebaseAuth.getInstance();
myDatabase = FirebaseDatabase.getInstance().getReference();
book1display = (TextView) findViewById(R.id.book1display);
book2display = (TextView) findViewById(R.id.book2display);
book3display = (TextView) findViewById(R.id.book3display);
book4display = (TextView) findViewById(R.id.book4display);
book5display = (TextView) findViewById(R.id.book5display);
book6display = (TextView) findViewById(R.id.book6display);
book7display = (TextView) findViewById(R.id.book7display);
String user_id = myAuth.getCurrentUser().getUid();
DatabaseReference userid_database = myDatabase.child(user_id);
DatabaseReference book1 = userid_database.child("Books").child("Book 1").child("Page");
DatabaseReference book2 = userid_database.child("Books").child("Book 2").child("Page");
DatabaseReference book3 = userid_database.child("Books").child("Book 3").child("Page");
DatabaseReference book4 = userid_database.child("Books").child("Book 4").child("Page");
DatabaseReference book5 = userid_database.child("Books").child("Book 5").child("Page");
DatabaseReference book6 = userid_database.child("Books").child("Book 6").child("Page");
DatabaseReference book7 = userid_database.child("Books").child("Book 7").child("Page");
book1.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book1display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
book2.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book2display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
book3.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book3display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
book4.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book4display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
book5.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book5display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
book6.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book6display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
book7.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String text = dataSnapshot.getValue(String.class);
book7display.setText(text);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
}
Below is an example output. I want to get the numbers that in the picture for make a calculation in the another activity.
This is my other activity:
public class HowMuch extends AppCompatActivity
private TextView howmuch1,howmuch2;
TextView hay;
Button button2;
private DatabaseReference myDatabase;
private FirebaseAuth myAuth;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_how_much);
myAuth=FirebaseAuth.getInstance();
myDatabase= FirebaseDatabase.getInstance().getReference();
howmuch1=(TextView)findViewById(R.id.howmuch1);
howmuch2=(TextView)findViewById(R.id.howmuch2);
hay=(TextView)findViewById(R.id.hay);
String user_id= myAuth.getCurrentUser().getUid();
DatabaseReference userid_database=myDatabase.child(user_id);
DatabaseReference book1=userid_database.child("Books").child("Book 1").child("Page");
DatabaseReference book2=userid_database.child("Books").child("Book 2").child("Page");
book1.addValueEventListener(new ValueEventListener()
{
#Override
public void onDataChange(DataSnapshot dataSnapshot)
{
String text= dataSnapshot.getValue(String.class);
int value=Integer.parseInt(text);
int value1=value/2;
String x= String.valueOf(value1);
howmuch1.setText(x);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
If I write like that for book2, book3 etc. I can make calculattion but I also want to make sum of these values. Hovewer, I couldn't transfer values of them to make new calculation. I tried to transfer values from my DisplayBooks activity writing this:
public void transfer(View view){
String value = book1display.getText().toString();
Intent intent = new Intent(DisplayBooks.this, HowMuch.class);
intent.putExtra("key",value);
startActivity(intent);
}
And adding this to HowMuch class:
String value = getIntent().getExtras().getString("key");
hay.setText(value);
But it didn't work.
It should be
String value = getIntent().getStringExtra("key");
hay.setText(value);
Edit: links for reference:
Send data
https://developer.android.com/training/sharing/send.html
Receive data https://developer.android.com/training/sharing/receive.html
Bundle receivedBundle = getIntent().getExtras();
if (receivedBundle != null) {
String extraString = receivedBundle.getString("key");
int extraInt = receivedBundle.getInt("key");
}