Membuat Aplikasi Chatting Part 4 - Menambahkan Teman

 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fabAdd"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="16dp"
        android:layout_marginBottom="16dp"
        android:clickable="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:srcCompat="@drawable/ic_baseline_add_24" />
</androidx.constraintlayout.widget.ConstraintLayout>

dialog_add.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    >

    <com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/edtID"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="UserID" />

        <Button
            android:id="@+id/btnOk"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Ok" />
    </com.google.android.material.textfield.TextInputLayout>
</LinearLayout>

MainActivity.java

public class MainActivity extends AppCompatActivity {

    private FirebaseAuth mAuth;
    private FirebaseAuth.AuthStateListener mAuthListener;
    private FirebaseFirestore db;
    private FloatingActionButton fabAdd;
    private String uid;

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

        mAuth = FirebaseAuth.getInstance();
        db = FirebaseFirestore.getInstance();

        mAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                if (firebaseAuth.getCurrentUser() == null) {
                    Intent i = new Intent(MainActivity.this,LoginActivity.class);
                    i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
                    startActivity(i);
                    finish();
                } else {
                    goMain();
                }
            }
        };
    }

    private void goMain() {
        FirebaseUser currentUser = mAuth.getCurrentUser();
        uid = currentUser.getUid();

        fabAdd = findViewById(R.id.fabAdd);
        fabAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                final Dialog dialog = new Dialog(MainActivity.this);
                dialog.setTitle("Enter User UID");
                dialog.setContentView(R.layout.dialog_add);
                dialog.show();

                final EditText edtID = dialog.findViewById(R.id.edtID);
                Button btnOk = dialog.findViewById(R.id.btnOk);

                btnOk.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        String idUser = edtID.getText().toString();
                        if (TextUtils.isEmpty(idUser)) {
                            edtID.setError("required");
                        } else {
                            db.collection("user").whereEqualTo("id",idUser)
                                    .get().addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
                                        @Override
                                        public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
                                            if(queryDocumentSnapshots.isEmpty()) {
                                                edtID.setError("ID not found");
                                            } else {
                                                for (DocumentSnapshot documentSnapshot : queryDocumentSnapshots.getDocuments()) {
                                                    String uidFriend = documentSnapshot.getId();
                                                    if (uid.equals(uidFriend)) {
                                                        edtID.setError("wrong ID");
                                                    } else {
                                                        dialog.cancel();
                                                        checkFriendExist(uidFriend);
                                                    }
                                                }
                                            }
                                        }
                            });
                        }
                    }
                });
            }
        });
    }

    private void checkFriendExist(final String uidFriend) {
        db.collection("user").document(uid).collection("friend").document().get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
            @Override
            public void onComplete(@NonNull Task<DocumentSnapshot> task) {
                if(task.isSuccessful()) {
                    DocumentSnapshot documentSnapshot = task.getResult();
                    if (documentSnapshot.exists()) {
                        String idChatRoom = documentSnapshot.get("idChatRoom", String.class);
                        goChatRoom(idChatRoom,uidFriend);
                    } else {
                        createNewChatRoom(uidFriend);
                    }
                }
            }
        });
    }

    private void createNewChatRoom(final String uidFriend) {
        HashMap<String,Object> dataChatRoom = new HashMap<>();
        dataChatRoom.put("dateAdded", FieldValue.serverTimestamp());
        db.collection("chatRoom").document(uid+uidFriend).set(dataChatRoom).addOnSuccessListener(new OnSuccessListener<Void>() {
            @Override
            public void onSuccess(Void aVoid) {
                //write user data
                HashMap<String,Object> dataFriend = new HashMap<>();
                dataFriend.put("idChatRoom",uid+uidFriend);
                db.collection("user").document(uid).collection("friend").document(uidFriend).set(dataFriend).addOnSuccessListener(new OnSuccessListener<Void>() {
                    @Override
                    public void onSuccess(Void aVoid) {
                        //write on user's friend data
                        HashMap<String,Object> dataUserFriend = new HashMap<>();
                        dataUserFriend.put("idChatRoom",uid+uidFriend);
                        db.collection("user").document(uidFriend).collection("friend").document(uid).set(dataUserFriend).addOnSuccessListener(new OnSuccessListener<Void>() {
                            @Override
                            public void onSuccess(Void aVoid) {
                                goChatRoom(uid+uidFriend,uidFriend);
                            }
                        });
                    }
                });
            }
        });
    }

    private void goChatRoom(String idChatRoom, String uidFriend) {
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        int id = item.getItemId();

        if (id == R.id.action_logout) {
            FirebaseAuth.getInstance().signOut();
            Intent i = new Intent(MainActivity.this,LoginActivity.class);
            i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
            startActivity(i);
            finish();
        } else if (id == R.id.action_profile) {
            Intent i = new Intent(MainActivity.this,ProfileActivity.class);
            startActivity(i);
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    protected void onStart() {
        super.onStart();
        mAuth.addAuthStateListener(mAuthListener);
    }

    @Override
    protected void onStop() {
        super.onStop();
        mAuth.removeAuthStateListener(mAuthListener);
    }
}

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