How to get firebase database category data by id and show that data in seperate recyclerview?

Question

I'm a newbie in firebase database and I'm trying to retrieve data like this in android into two recyclerviews when on click on sermoncategory recycerview show all the sermons of that data can anyone help me with this? with android code also thanks!!

"sermons"
        |_ _"0"
              |_ "sermonurl": "https://..."
              |_ "sermontitle": "Title"
              |_ "sermoncategory": "2"

        |_ _"1"
              |_ "sermonurl": "https://..."
              |_ "sermontitle": "Title"
              |_ "sermoncategory": "3"

    "sermoncategory"
           |
           |_ "2" 
               |_"categorytitle": "Covenant of Blessing"
               |_"categoryimageurl": "https://..."
               |_"categorydesciption":"bla bla bla"

           |_ "3"
               |_"categorytitle": "Healing"
               |_"categoryimageurl": "https://..."
               |_"categorydesciption":"bla bla bla"

Can you kindly be more precise? What data do you want to retrieve from the database? — PradyumanDixit, Oct 15 '18 at 08:19
I want to link both nodes just like SQL database keys as the firebase database is not relational so...like get all movie categories genres(comedy, drama, action..etc) in one recycerview and when onclick link it to the specified data by their id — Vãmsi Madduluri, Oct 15 '18 at 08:20
From what I'm getting you want to first know the category of your sermon and if suppose that category is 2, you want to display the data of sermoncategory with node 2, right? — PradyumanDixit, Oct 15 '18 at 08:22
**[This](https://stackoverflow.com/questions/49383687/how-can-i-retrieve-data-from-firebase-to-my-adapter/49384849)** is a recommended way in which you can retrieve data from a Firebase Realtime database and display it in a `RecyclerView` using `FirebaseRecyclerAdapter`. — Alex Mamo, Oct 15 '18 at 08:23
thanks, @AlexMamo for helping me out about the recycleview adapter. — Vãmsi Madduluri, Oct 15 '18 at 08:32
Possible duplicate of [Getting a specific category of data from firebase](https://stackoverflow.com/questions/51406414/getting-a-specific-category-of-data-from-firebase) — RileyManda, Feb 28 '19 at 07:19

PradyumanDixit · Accepted Answer · 2018-10-15T08:42:58.920

1

If you want to get sermons with sermoncategory as 2, you may use orderByChild() query like this:

DatabaseReference ref = FirebaseDatabase.getInstance().getReference().child("sermons");

ref.orderByChild("sermoncategory").equalTo(2).addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
           // this dataSnapshot will have all the sermons with sermocategory as 2
        }

        @Override
        public void onCancelled(FirebaseError firebaseError) {
            Log.e("MainActivity", "onCancelled", firebaseError.toException());
        }
    });

edited Oct 15 '18 at 08:42

answered Oct 15 '18 at 08:17

PradyumanDixit

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so, when I create a recycle view of data snapshot of sermons with onclick i need to invoke this? or i need to query? – Vãmsi Madduluri Oct 15 '18 at 08:37
This code will store all the sermons with sermoncategory as 2 in dataSnapshot, and you can use it to populate your RecyclerView. – PradyumanDixit Oct 15 '18 at 08:44
@VãmsiMadduluri if this answer helped you, consider marking it as correct and upvoting it, I'd appreciate that. Cheers :) – PradyumanDixit Oct 15 '18 at 09:21

How to get firebase database category data by id and show that data in seperate recyclerview?

1 Answers1