Module 형식으로 게시판 만들기 (클라이언트)

설명

Module 형식으로 게시판 만들기 ( read, create 만 작성 )

KeyPoint

HttpURLConnection OR Retrofit2
- HttpURLConnection 사용하기
  - 참조 : HttpURLConnection
- Retrofit2 사용(RxJava)
  - 참조 : Retrofit2, RxJava

RecyclerView 스크롤 시 데이터 호출하기

private int page = 1;
// addOnScrollListener를 달아서 호출하기
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
    @Override
    public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);
    }

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);

        int totalCount = recyclerView.getLayoutManager().getItemCount();
        int lastPosition = ((LinearLayoutManager)recyclerView.getLayoutManager()).findLastVisibleItemPosition();

        // 마지막 Position 이 totalCount-1 일때 load 한다
        if (lastPosition == totalCount-1) {
            load();
        }
    }
});

// load 시
if (page == 1) {
    setAdapter(data.getData());
} else {
    addAdapter(data.getData());
}
page++;

Code Review

MainActivity.java

RecyclerView 를 통해 데이터 목록을 보여준다.

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

  private int page = 1;
  private String url = "http://192.168.0.156:8090/bbs?type=all&page=";

  private RecyclerView recyclerView;
  private FloatingActionButton fab;
  private ProgressBar progressBar;
  private MainAdapter adapter;
  private Intent write;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      write = new Intent(this, WriteActivity.class);
      initView();
      load();
  }

  private void initView() {
      recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
      recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
          @Override
          public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
              super.onScrollStateChanged(recyclerView, newState);
          }

          @Override
          public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
              super.onScrolled(recyclerView, dx, dy);

              int totalCount = recyclerView.getLayoutManager().getItemCount();
              int lastPosition = ((LinearLayoutManager)recyclerView.getLayoutManager()).findLastVisibleItemPosition();

              if (lastPosition == totalCount-1) {
                  load();
              }
          }
      });

      fab = (FloatingActionButton) findViewById(R.id.fab);
      progressBar = (ProgressBar) findViewById(R.id.progressBar);
      fab.setOnClickListener(this);
  }

  private void load() {

      // 1. 서비스 생성
      iBbs service = ServiceGenerator.createBbs(iBbs.class);
      // 2. Observer 생성 ( Emitter 생성 )
      Observable<Result> observable = service.getData("all", page);
      observable.subscribeOn(Schedulers.io())
              .observeOn(AndroidSchedulers.mainThread())
              .subscribe(
                      data -> {
                          if(data.isSuccess()){
                              if (page == 1) {
                                  setAdapter(data.getData());
                              } else {
                                  addAdapter(data.getData());
                              }
                              page++;
                          }
                      }
              );
  }

  private void setAdapter(List<Data> dataList) {
      adapter = new MainAdapter(dataList);
      recyclerView.setLayoutManager(new LinearLayoutManager(this));
      recyclerView.setAdapter(adapter);
  }

  private void addAdapter(List<Data> dataList) {
      adapter.addDataAndRefresh(dataList);
  }

  @Override
  public void onClick(View v) {
      int id = v.getId();
      switch (id) {
          case R.id.fab:
              startActivityForResult(write, Const.REQ_WRITE);
              break;
      }
  }

  @Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
      switch (requestCode) {
          case Const.REQ_WRITE:
              if (resultCode == RESULT_OK) {
                  page = 1;
                  load();
              }
              break;
      }
  }
}

WriteActivity.java

글을 작성하는 Activity 이다. String 데이터들을 JSON 으로 변환하고 Body에 담아 보낸다.

public class WriteActivity extends AppCompatActivity {
  private Button btnPost;
  private EditText editTitle;
  private EditText editContent;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_write);
      initView();
      btnPost.setOnClickListener(new View.OnClickListener() {
          @Override
          public void onClick(View v) {
              write();
          }
      });
  }

  private void write() {
      String title = editTitle.getText().toString();
      String content = editContent.getText().toString();

      Data data = new Data();
      data.setTitle(title);
      data.setContent(content);
      String dID = android.provider.Settings.Secure.getString(
              getContentResolver(), Settings.Secure.ANDROID_ID);
      data.setUser_id(dID);

      iBbs service = ServiceGenerator.createBbs(iBbs.class);

      Observable<Result> observable = service.sendPost(data);
      observable.subscribeOn(Schedulers.io())
              .observeOn(AndroidSchedulers.mainThread())
              .subscribe(result -> {
                  if (result.isSuccess()) {
                      setResult(RESULT_OK);
                  } else {
                      Toast.makeText(WriteActivity.this, "오류", Toast.LENGTH_SHORT).show();
                      setResult(RESULT_CANCELED);
                  }
                  finish();
              });
  }

  private void initView() {
      btnPost = (Button) findViewById(R.id.btnPost);
      editTitle = (EditText) findViewById(R.id.editTitle);
      editContent = (EditText) findViewById(R.id.editContent);
  }
}

ServiceGenerator.java

Retrofit2 Service 를 생성하는 class

public class ServiceGenerator {

    public static <T> T createBbs(Class<T> className){
        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(Const.BBS_URL)
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        return retrofit.create(className);
    }
}

iBbs.java

url 정의

public interface iBbs {

    @GET("bbs")
    Observable<Result> getData(@Query("type") String sort, @Query("page") int page);

    @POST("bbs")
    Observable<Result> sendPost(@Body Data data);

}

Hooooong/DAY33_BBS-Android-

Module 형식으로 게시판 만들기 (클라이언트)

설명

KeyPoint

Code Review