How can i pass user id from my adapter to activity

Question

i am trying to pass holders user.getID to my attendance activity how can i pass users id from my adapter to attendance activity

this is my attendance activity

        reference = FirebaseDatabase.getInstance().getReference("parent");

        intent = getIntent();
        final String currentSubject = intent.getStringExtra("currentSubject");
        reference.addValueEventListener(new ValueEventListener() {
            @RequiresApi(api = Build.VERSION_CODES.O)
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                for (DataSnapshot snapshot : dataSnapshot.getChildren()) {

                    final User user = snapshot.getValue(User.class);

                    ZoneId zonedId = ZoneId.of("America/Montreal");
                    final LocalDate today = LocalDate.now(zonedId);

                        reference = FirebaseDatabase.getInstance().getReference("attendance").child(user.getSchoolcode()).child(grade.getText().toString() + " " + section.getText().toString()).child(currentSubject).child(today.toString()).child(userID);

                        reference.addValueEventListener(new ValueEventListener() {
                            @Override
                            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

                                HashMap<String, Object> hashMap = new HashMap<>();
                                hashMap.put("attendance", "yes");
                                reference.updateChildren(hashMap);
                            }

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

                            }
                        });
                    }
            }

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

i want to pass it from adapter to this this is my adapter

public class StudentAdapter extends RecyclerView.Adapter<StudentAdapter.ViewHolder> {

    private Context context;
    private List<User> users;


    public StudentAdapter(Context context, List<User> users) {
        this.context = context;
        this.users = users;
    }
    DatabaseReference reference;

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(context).inflate(R.layout.student_item, parent, false);
        return new StudentAdapter.ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull final ViewHolder holder, int position) {
        final User user = users.get(position);

        holder.studentName.setText(user.getStudentname() + " " + user.getLastname());

    }

    @Override
    public int getItemCount() {
        return users.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder {
        public TextView studentName;
        public Switch aSwitch;

        public ViewHolder(View itemView) {
            super(itemView);

            studentName = itemView.findViewById(R.id.studentName);
            aSwitch = itemView.findViewById(R.id.attendanceSwitch);
        }
    }

this is my adapter which holds the recyclerview,i am trying to get id of users viewed on attendance activities recyclerview

milad salimi · Answer 1 · 2020-05-21T08:37:42.793

0

A way that you can use is callback :

In your adapter define an interface like this :

public class StudentAdapter extends RecyclerView.Adapter<StudentAdapter.ViewHolder> {

 private SendCallBack mCallback;

    interface SendCallBack {
        void send(int id);
    }

//Initial callback in constructor
   public StudentAdapter(Context context, List<User> users,SendCallBack callback) {
        this.context = context;
        this.users = users;
        mCallback = callback;
    }

//Now in where that you want to pass data use this

    mCallback.send(user.getID);

}

Now in your activity implement the callback like this :

public class YourActivty implements  YourAdapter.SendCallback {

    @Override
    public void send(int id) {


    }

//For pass callBack for your adapter constructor use this

}

For other ways you can use this link.

edited May 21 '20 at 08:37

answered May 21 '20 at 06:12

milad salimi

1,580
2
12
31

i am not trying to open a new activity – Tripping May 21 '20 at 06:31
Then you can use callback , you can use this link in bottom of my answer.@Tripping – milad salimi May 21 '20 at 06:33
@Tripping , Is it useful? – milad salimi May 21 '20 at 07:30
showign encompitable types on ```mCallback = callback;``` – Tripping May 21 '20 at 07:48
... just change `Callback mCallback;` to `SendCallBack mCallback;` inside your `Adapter`, and remember to use objects of classes which you've declared. – SkypeDogg May 21 '20 at 08:02
when i declare ```final User user = user.get(position)``` postion cannot resolve symbol – Tripping May 21 '20 at 08:24
OMG , what is this `final User user = user.get(position)` you should use `User user = userList.get(position)` @Tripping – milad salimi May 21 '20 at 08:39
Man, you're really "tripping". You were given full answer which is supposed to work, and you try to do things like `user.get(position)` where user is an object, and all you can say is "its not working". You have full answer, which is correct one, so now you should adjust it to your needs. – SkypeDogg May 21 '20 at 12:26
@SkypeDogg dude ```user.getID``` will work if i declare user or user can not be resolved i think you are the one tripping – Tripping May 21 '20 at 13:32
`"final User user = user.get(position)"` - It's taken from your comment. – SkypeDogg May 21 '20 at 13:36

How can i pass user id from my adapter to activity

1 Answers1