CODEWITHSUNDEEP
javaandroidfirebasefirebase-realtime-database
iatharva
iatharva

Reputation: 79

How to get the count of total likes from all posts which are posted by one user in android firebase?

The structure in which I store the likes of a post is as shown below :

show in this image

This is how I store the information of a post:

post information

UID is of the user ID of the user who posted the post of course.

I want to get the total number of likes that a particular user with UID got on all of his posts

For example:

A user with uid: Avvj7v9v has two posts with 4 and 2 likes, respectively. So, the total number of likes that all of his posts got is 6.

I want a way to get that number of likes which is 6 in this example.

Upvotes: 2

Views: 815

Answers (2)

auspicious99
auspicious99

Reputation: 4311

Go to databaseReference.child("Posts") and loop through all the posts, find those whose uid child matches the desired user, and keep that subset of post IDs, say in an ArrayList, postsOfTheUser.

Next, go to databaseReference.child("Likes") and loop through all the likes. Ignore all children whose post ID is not in postsOfTheUser, but those whose post ID is in postsOfTheUser, proceed to sum the likes, using getChildrenCount() for each of the posts.

Upvotes: 1

Ticherhaz FreePalestine
Ticherhaz FreePalestine

Reputation: 2377

You can do something like this. 

databaseReference.child("Likes").addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
    long sum = 0;
    for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
        long size = snapshot.child(UUID).getChildrenCount();
        sum += size;
        textView.setText("Total Likes for this User: " + sum);
    }
}

@Override
public void onCancelled(@NonNull DatabaseError databaseError) {

}
});

Upvotes: 0

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