Android Alert Dialog Box Not showing Up Whats Wrong?

Question

I was following a Youtube tutorial to show alert Dialog Box on my View Holder.In order to send the user to a Specific Activity based on their selection.But when I click on the View Holder it is not even showing up or doing anything.However the Onclick Listener is working fine.I have tried it with a Toast message and the Toast is showing.

private RecyclerView myFriendsList;
private DatabaseReference FriendsRef,UsersRef;
private FirebaseAuth mAuth;
private String online_user_id;
private TextView friends;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_friends);

    myFriendsList = (RecyclerView) findViewById(R.id.friends_list);
    friends = (TextView) findViewById(R.id.all_friends);
    myFriendsList.setHasFixedSize(true);
    LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
    linearLayoutManager.setReverseLayout(true);
    linearLayoutManager.setStackFromEnd(true);
    myFriendsList.setLayoutManager(linearLayoutManager);

    mAuth = FirebaseAuth.getInstance();
    online_user_id = mAuth.getCurrentUser().getUid();
    FriendsRef = FirebaseDatabase.getInstance().getReference().child("Friends").child(online_user_id);
    UsersRef = FirebaseDatabase.getInstance().getReference().child("Users");

    DisplayAllFriends();
}

private void DisplayAllFriends() {

    FirebaseRecyclerOptions<Friends> options=new FirebaseRecyclerOptions.Builder<Friends>().
            setQuery(FriendsRef ,Friends.class).build();
    FirebaseRecyclerAdapter<Friends, FriendsViewHolder> adapter = new FirebaseRecyclerAdapter<Friends, FriendsViewHolder>(options) {
        @Override
        protected void onBindViewHolder(@NonNull final FriendsViewHolder holder,int position, @NonNull Friends model) {


            holder.setDate(model.getDate());
            final String userIDs = getRef(position).getKey();

            UsersRef.child(userIDs).addValueEventListener(new ValueEventListener() {
                @Override
                public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

                    if(dataSnapshot.exists())
                    {

                        final String username = dataSnapshot.child("fullname").getValue().toString();
                        final String profileimage = dataSnapshot.child("profileimage").getValue().toString();


                        holder.setFullname(username);
                        holder.setProfileimage(getApplicationContext(),profileimage);

                        holder.mView.setOnClickListener(new View.OnClickListener() {
                           @Override
                           public void onClick(View v) {

                               CharSequence options[] = new CharSequence[]
                                       {
                                               username + "'s Profile",
                                               "Send Message"

                                       };


                               AlertDialog.Builder builder = new 
                               AlertDialog.Builder(FriendsActivity.this);
                               builder.setTitle("Select Options");

                               builder.setItems(options, new DialogInterface.OnClickListener() {
                                   @Override
                                   public void onClick(DialogInterface dialog, int which) {

                                       if(which == 0)
                                       {

                                           Intent ProfileIntent = new 
                                           Intent(FriendsActivity.this,PersonProfileActivity.class);
                                           ProfileIntent.putExtra("visit_user_id",userIDs);
                                           startActivity(ProfileIntent);

                                       }

                                       if(which == 1)
                                       {

                                           Intent ChatIntent = new 
                                           Intent(FriendsActivity.this,ChatActivity.class);
                                           ChatIntent.putExtra("visit_user_id",userIDs);
                                           startActivity(ChatIntent);

                                       }
                                   }
                               });
                           }
                       });

                    }

                }

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

                }
            });
        }

        @NonNull
        @Override
        public FriendsViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
            View view= LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.all_users_display_layout,viewGroup,false);

            FriendsActivity.FriendsViewHolder holder=new FriendsActivity.FriendsViewHolder(view);
            return holder;
        }

    };

    myFriendsList.setAdapter(adapter);
    adapter.startListening();
}

public static class FriendsViewHolder extends RecyclerView.ViewHolder

{

    View mView;

    public FriendsViewHolder(@NonNull View itemView) {
        super(itemView);

        mView = itemView;

    }
    public void setProfileimage(Context ctx, String profileimage) {

        CircleImageView myImage = (CircleImageView) mView.findViewById(R.id.all_users_profile_image);
        PicassoProvider.get().load(profileimage).placeholder(R.drawable.profile).into(myImage);
    }

    public void setFullname(String fullname) {
        TextView myName = (TextView) mView.findViewById(R.id.all_users_profile_full_name);
        myName.setText(fullname);

    }


    public void setDate(String date) {
        TextView friendsDate = (TextView) mView.findViewById(R.id.all_users_status);
        friendsDate.setText("Friends Since: " + date);

    }
}

Answer 1

builder.show(); would let the dialog appear when the method is run.

Answer 2

You forgot to call builder.show() in your alert dialog builder. You can call this method after builder.setItems(...)