I want to fetch the all uid's of the doctor whose category is "abc"(example) and then store those retrieved uid's into an array list.
I want same results as displayed by the below sql query:
select uid from doctors where category = "abc";
Code for next activity is written below
private void loadDoctors() {
ArrayList<String> uid = getIntent().getStringArrayListExtra("doctor_list");
for (int i =0;i<uid.size();i++){
DatabaseReference doctors = FirebaseDatabase.getInstance().getReference("Doctors").child(uid.get(i));
Adapter = new FirebaseRecyclerAdapter<DoctorModel, DoctorViewHolder>(
DoctorModel.class,
R.layout.doctors_home,
DoctorViewHolder.class,
doctors
) {
#Override
protected void populateViewHolder(final DoctorViewHolder viewHolder, final DoctorModel model, int position) {
viewHolder.doctor_name.setText(model.getName());
Glide.with(Doctors.this).load(model.getProfileimage()).into(viewHolder.doctor_image);
viewHolder.qualification.setText(model.getQualification());
viewHolder.rating.setText(model.getRating());
}
};
Adapter.notifyDataSetChanged();
doctors_list.setAdapter(Adapter);
}
To solve this, please use the following lines of code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference doctorsRef = rootRef.child("Doctors");
Query categoryQuery = doctorsRef.orderByChild("category").equalTo("Cardiology");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
List<String> uidList = new ArrayList<>();
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String uid = ds.getKey();
uidList.add(uid);
}
//Do what you need to do with your list
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d("TAG", databaseError.getMessage()); //Don't ignore errors!
}
};
categoryQuery.addListenerForSingleValueEvent(valueEventListener);
At the end, you'll have a list full of uids. One more thing to note, because Firebease API is asynchronous, you will be able to use that list only inside onDataChange() method.
Related
What I really need is to show every value in the "Income" field in TextView.
250
105
Is this possible? If it is possible please help me.
This is how I insert values to database
private void addReport() {
Float total_Income = Float.valueOf(tv_total_income.getText().toString());
String current_date = tv_current_date.getText().toString();
SimpleDateFormat sdf = new SimpleDateFormat("MMMM");
String currentDateandTime = sdf.format(new Date());
FirebaseDatabase mDatabase = FirebaseDatabase.getInstance();
DatabaseReference mDbRef = mDatabase.getReference("Reports"+"/"+currentDateandTime+"/"+current_date).child("Date");
mDbRef.setValue(current_date);
DatabaseReference mDbRef1 = mDatabase.getReference("Reports"+"/"+currentDateandTime+"/"+current_date).child("Income");
mDbRef1.setValue(total_Income);
}
While Sairaj Sawant's answer might work, keep in mind that there is no need to attach a listener at every iteration of the loop. A more convenient solution is to attach a listener only once, like in the following lines of code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference juneRef = rootRef.child("Reports").child("June");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String totalIncome = "";
for(DataSnapshot ds : dataSnapshot.getChildren()) {
totalIncome = totalIncome + ds.child("Income").getValue(String.class) + " ";
}
Log.d("TAG", totalIncome);
textView.setText(totalIncome);
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d("TAG", databaseError.getMessage()); //Don't ignore errors!
}
};
juneRef.addListenerForSingleValueEvent(valueEventListener);
This code will work only if the Income property is of type String, as it is set in your 20-06-2020 child. However, the above code will not work if the value is set as an Integer as it set in your second 21-06-2020 child. Remember, both types of values must match. You either set both as String and the above code will work, or you set them as numbers, case in which you should use this line:
totalIncome = totalIncome + ds.child("Income").getValue(Long.class) + " ";
Try accessing the children of June under Reports and looping through to get income as below :
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference reportsRef = rootRef.child("Reports").child("June");
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot ds : dataSnapshot.getChildren()) {
String key = ds.getKey();
DatabaseReference keyRef = rootRef.child(key).child("income");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot ds1 : dataSnapshot.getChildren()) {
String income = ds1.getValue(String.class);
Log.d("TAG", income);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
keyRef.addListenerForSingleValueEvent(valueEventListener);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
reportsRef.addListenerForSingleValueEvent(eventListener);
I am trying to create child inside child -LoVaDPuBRr4K2JSkc_j , but how?
Code :
firebaseAuth = FirebaseAuth.getInstance();
firebaseDatabase = FirebaseDatabase.getInstance();
databaseDocument = firebaseDatabase.getReference(firebaseAuth.getUid()).child("Document");
To create a child in -LoVaDPuBRr4K2JSkc_j, you can do:
databaseDocument.child("-LoVaDPuBRr4K2JSkc_j").child("newProperty").setValue("new value");
If you want to generate a new child with an auto-generated key, it'd be:
databaseDocument.child("-LoVaDPuBRr4K2JSkc_j").push().setValue("new value");
Both of these assume that you know the -LoVaDPuBRr4K2JSkc_j value in your code. This is required to be a able to add a child, as writing to a location in the database requires that you know the full path to that location.
You'll not want to hardcode this key of course, so there are two common options to have the key:
Pass it along your app from the moment when you loaded the data.
Use some other value of the node that allows you to perform a query on the database to look up the key.
The simplest solution to add a new property inside your -LoVaDPuBRr4K2JSkc_j object would be use that pushed id in your reference like in the following lines of code:
String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference ref = rootRef.child(uid).child("Document").child("-LoVaDPuBRr4K2JSkc_j");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
dataSnapshot.getRef().child("newProperty").setValue("newValue");
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d(TAG, databaseError.getMessage()); //Don't ignore errors!
}
};
ref.addListenerForSingleValueEvent(valueEventListener);
Edit:
Accodring to your comment, if you have more than one key, then you should use a query. The following code will do the trick:
String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
Query query = rootRef.child(uid).child("Document").orderByChild("inspectorName").equalTo("Test");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
ds.getRef().child("newProperty").setValue("newValue");
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d(TAG, databaseError.getMessage()); //Don't ignore errors!
}
};
query.addListenerForSingleValueEvent(valueEventListener);
My code and its work :
firebaseAuth = FirebaseAuth.getInstance();
firebaseDatabase = FirebaseDatabase.getInstance();
databaseProduct = firebaseDatabase.getReference(firebaseAuth.getUid()).child("Document");
String id = databaseProduct.push().getKey();
final String productID = databaseProduct.child(id).child("Product").push().getKey();
final Items items = new Items(productID, dates, nameInspector, locate, product, priceProduct, amount, code);
databaseProduct.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
for (DataSnapshot getDocumentKey : dataSnapshot.getChildren()) {
String getDocumentID = getDocumentKey.getKey();
String sameDocumentID = getDocumentKey.child("documentID").getValue().toString();
if (getDocumentID.contentEquals(sameDocumentID)) {
databaseProduct.child(getDocumentID).child("Product").child(productID).setValue(items);
}
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
I want to retrieve data for a specific child, how I can write the code? I try a lot, but it did not work:"([ like in my database here how to get the tasks for specific child like lubna and gets all it's child?
Initialize class variables:
private DatabaseReference mDatabase;
mDatabase = FirebaseDatabase.getInstance().getReference();
private DatabaseReference lubnaRef = mDatabase.child("tasks/Lubna");
And then for testing purposes I am assuming you are calling this in your onCreate method of your activity, you'd add the following assuming you do not have a data model for it:
lubnaRef.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
//These are all of your children.
Map<String, Object> lubna = (Map<String, Object>) dataSnapshot.getValue();
for (String childKey: lubna.keySet()) {
//childKey is your "-LQka.. and so on"
//Your current object holds all the variables in your picture.
Map<String, Object> currentLubnaObject = (Map<String, Object>) lubna.get(childKey);
//You can access each variable like so: String variableName = (String) currentLubnaObject.get("INSERT_VARIABLE_HERE"); //data, description, taskid, time, title
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
To solve this, please use the following lines of code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference lubnaRef = rootRef.child("tasks").child("Lubna");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String title = ds.child("title").getValue(String.class);
Log.d(TAG, title);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d(TAG, databaseError.getMessage());
}
};
lubnaRef.addListenerForSingleValueEvent(valueEventListener);
In the same way you get the title, you can also get the other values. The output in your logcat will be:
Homework
//and so on
I'm trying to create a Firebase Realtime database project in which the data stored is either type A or type B, etc. This is how it looks like on the console:
Firebase Database
The user can then add more posts, of which are saved to the database then displayed on a ListView.
My Code
final DatabaseReference room = FirebaseDatabase.getInstance().getReference().getRoot();
chatRoomAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, chatList);
lvChatRoom.setAdapter(chatRoomAdapter);
btnAddChatRoomMa.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
strChatRoomName = etChatRoom.getText().toString();
etChatRoom.setText("");
Map<String, Object> chatMap = new HashMap<>();
chatMap.put(strChatRoomName + " -TYPEA", "");
room.updateChildren(chatMap);
}
});
room.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
Iterator iterator = dataSnapshot.getChildren().iterator();
Set<String> set = new HashSet<>();
while (iterator.hasNext()) {
set.add(((DataSnapshot) iterator.next()).getKey());
}
chatList.clear();
chatList.addAll(set);
chatRoomAdapter.notifyDataSetChanged();
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
I only want to show for instance, TYPEA (on the database), without displaying the rest. How can I achieve this?
If you want to display only the value of the property TYPEA, please use the following code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference ref = rootRef.child("fruit-TYPEA");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String fruitTYPEA = dataSnapshot.getValue(String.class);
Log.d("TAG", fruitTYPEA);
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
ref.addListenerForSingleValueEvent(valueEventListener);
The output will be: orange.
I want to retrieve from firebase database and I already have setup my model to put content in place. I succeeded to retrieve data from one single node but I am unable to do so where I need data from 2 nodes which I want to show it in say Recycler View. However, where I get the success is completely different fragment.
First, I will show you my code for retrieving data from just one node and it is working for me.
Here's the code which is working for one node in different fragment.
Working-Fragment
private void updateArrayList() {
DatabaseReference reference = FirebaseDatabase.getInstance().getReference();
Query query = reference
.child(getString(R.string.dbname_posts))
.child(FirebaseAuth.getInstance().getCurrentUser().getUid());
query.addChildEventListener(new ChildEventListener() {
#Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
data.add(dataSnapshot.getValue(Userpost.class));
adapter.notifyDataSetChanged();
}
Above Code works perfectly.
Now Non-Working Code which doesn't pull anything.
private void updateArrayList() {
DatabaseReference reference = FirebaseDatabase.getInstance().getReference();
Query query = reference
.child(getString(R.string.dbname_posts)).child("profile_photo")
.child(getString(R.string.dbname_user_account_settings))
.child("profile_photo");
query.addChildEventListener(new ChildEventListener() {
#Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
data.add(dataSnapshot.getValue(Userpost.class));
adapter.notifyDataSetChanged();
}
This is a snapshot for firebase database
Firebase Database Snapshot
I made the question as clear as possible on my end.
Thank you all in advance.
To get those values from a specific post, please use the following code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference postIdRef = rootRef.child("posts").child(postId);
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String pheading = dataSnapshot.child("pheading").getValue(String.class);
String user_id = dataSnapshot.child("user_id").getValue(String.class);
Log.d("TAG", pheading + " / " + user_id);
DatabaseReference ref = rootRef.child("user_account_settings").child(user_id);
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot ds) {
String profile_photo = ds.child("profile_photo").getValue(String.class);
Log.d("TAG", profile_photo);
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
ref.addListenerForSingleValueEvent(valueEventListener);
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
postIdRef.addListenerForSingleValueEvent(eventListener);
In which postId is the id of the post from which you want to extract the data.