Android MVP 學習

標籤：

MVP -- Model View Presenter

MartinFowler 的 這篇文章 將MVP分為 SupervisingPresenter 和PassiveView

Android 中MVP 例子： https://github.com/antoniolg/androidmvp

先看一下項目的結構

                    

可以看出每個功能模組包含 XXActivity，XXView （Interface），XXPresenter（interface），XXPresenterImp

LoginView介面，負責邏輯處理

public interface LoginView {    public void showProgress();    public void hideProgress();    public void setUsernameError();    public void setPasswordError();    public void navigateToHome();}

LoginPresenter介面

public interface LoginPresenter {    public void validateCredentials(String username, String password);}

LoginActivity，實現了LoginView介面，實現了對應的方法，內部包含一個Presenter作為成員變數，presenterImp調用響應的方法進行UI更新與同步

public class LoginActivity extends Activity implements LoginView, View.OnClickListener {    private ProgressBar progressBar;    private EditText username;    private EditText password;    private LoginPresenter presenter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_login);        progressBar = (ProgressBar) findViewById(R.id.progress);        username = (EditText) findViewById(R.id.username);        password = (EditText) findViewById(R.id.password);        findViewById(R.id.button).setOnClickListener(this);        presenter = new LoginPresenterImpl(this);    }    @Override public void showProgress() {        progressBar.setVisibility(View.VISIBLE);    }    @Override public void hideProgress() {        progressBar.setVisibility(View.GONE);    }    @Override public void setUsernameError() {        username.setError(getString(R.string.username_error));    }    @Override public void setPasswordError() {        password.setError(getString(R.string.password_error));    }    @Override public void navigateToHome() {        startActivity(new Intent(this, MainActivity.class));        finish();    }    @Override public void onClick(View v) {        presenter.validateCredentials(username.getText().toString(), password.getText().toString());    }}

LoginPresenterImp，實現了LoginPresenter

ublic class LoginPresenterImpl implements LoginPresenter, OnLoginFinishedListener {    private LoginView loginView;    private LoginInteractor loginInteractor;    public LoginPresenterImpl(LoginView loginView) {        this.loginView = loginView;        this.loginInteractor = new LoginInteractorImpl();    }    @Override public void validateCredentials(String username, String password) {        loginView.showProgress();        loginInteractor.login(username, password, this);    }    @Override public void onUsernameError() {        loginView.setUsernameError();        loginView.hideProgress();    }    @Override public void onPasswordError() {        loginView.setPasswordError();        loginView.hideProgress();    }    @Override public void onSuccess() {        loginView.navigateToHome();    }}

整個項目架構中，將邏輯處理和UI同步更新從Activity中分離出來，代碼更加簡潔

對於MVP還不是太理解，還需要再多看例子啊

關於MVP的改進  ：部落格

Android MVP 學習