[Android Studio] TabBar Fragment 사용하기

📝탭바를 클릭하면 화면이 바뀌게 플래그먼트 셋팅하기

우선 메인액티비티에 아래 코드처럼 셋팅해준다

public class MainActivity extends AppCompatActivity {

    BottomNavigationView navigationView;
    // 각 프레그먼트를 멤버 변수로 만든다
    public Fragment firstFragment;
    public Fragment secondFragment;
    public Fragment thirdFragment;

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

        getSupportActionBar().setTitle("홈");

        navigationView = findViewById(R.id.bottomNavigationView);

        firstFragment = new FirstFragment();
        secondFragment = new SecondFragment();
        thirdFragment = new ThirdFragment();

        // 탭바를 누르면 동작하는 코드
        navigationView.setOnItemSelectedListener(new NavigationBarView.OnItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                int itemId = item.getItemId();
                Fragment fragment = null;

                if (itemId == R.id.firstFragment) {
                    fragment = firstFragment;
                    getSupportActionBar().setTitle("홈");
                } else if (itemId == R.id.secondFragment) {
                    fragment = secondFragment;
                    getSupportActionBar().setTitle("내 포스팅");
                } else if (itemId == R.id.thirdFragment) {
                    fragment = thirdFragment;
                    getSupportActionBar().setTitle("설정");
                }

                return loadFragment(fragment);
            }
        });
    }

    private boolean loadFragment(Fragment fragment) {
        if (fragment != null) {
            getSupportFragmentManager().beginTransaction().replace(R.id.fragment, fragment).commit();
            return true;
        } else {
            return false;
        }
    }
}

 

그리고 화면에 보여줄 플래그먼트의 자바 파일로 가서 onCreateView안에 아래 코드처럼 입력해서 사용한다

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.fragment_first, container, false);

    // 화면 연결은 위에서 만든 rootView으로 한다
    btnAdd = rootView.findViewById(R.id.btnAdd);
    progressBar = rootView.findViewById(R.id.progressBar);

    recyclerView = rootView.findViewById(R.id.recyclerView);
    recyclerView.setHasFixedSize(true);
    recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

    btnAdd.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(getActivity(), AddActivity.class);
            startActivity(intent);
        }
    });

    getNetworkData();

    return rootView;
}

전체 코드

/**
 * A simple {@link Fragment} subclass.
 * Use the {@link FirstFragment#newInstance} factory method to
 * create an instance of this fragment.
 */
public class FirstFragment extends Fragment {

    // TODO: Rename parameter arguments, choose names that match
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // TODO: Rename and change types of parameters
    private String mParam1;
    private String mParam2;

    public FirstFragment() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @param param1 Parameter 1.
     * @param param2 Parameter 2.
     * @return A new instance of fragment FirstFragment.
     */
    // TODO: Rename and change types and number of parameters
    public static FirstFragment newInstance(String param1, String param2) {
        FirstFragment fragment = new FirstFragment();
        Bundle args = new Bundle();
        args.putString(ARG_PARAM1, param1);
        args.putString(ARG_PARAM2, param2);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            mParam2 = getArguments().getString(ARG_PARAM2);
        }
    }

    Button btnAdd;
    RecyclerView recyclerView;
    PostingAdapter adapter;
    ArrayList<Posting> postingList = new ArrayList<>();

    ProgressBar progressBar;

    // 페이징 처리를 위한 변수
    int count = 0;
    int offset = 0;
    int limit = 7;
    private Posting selectedPosting;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.fragment_first, container, false);

        btnAdd = rootView.findViewById(R.id.btnAdd);
        progressBar = rootView.findViewById(R.id.progressBar);

        recyclerView = rootView.findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(getActivity(), AddActivity.class);
                startActivity(intent);
            }
        });

        getNetworkData();

        return rootView;
    }
}