andrid中mvp简单实例demo登录和注册

首先简单介绍一下MVP的构成及优缺点：
MVP的全称为Model-View-Presenter,
Model提供数据（网络请求、数据存储等）；
View负责页面显示；
Presenter负责逻辑的处理；
优点：主要就是将Model层和View层完全解耦，使得两者任一方的修改都不会对另一方产生影响，而是将逻辑处理放在了Presenter层；
缺点：显而易见，随着项目的增大，Presenter层也会变得臃肿，所以根据不同项目逻辑灵活的去使用Presenter也很重要；
之前有做过基于MVP的Android项目，根据别人写好的结构，无非就是填充代码，对于MVP整体的理解不够到位，所以该如何从头去理解一个MVP项目，对今后避免一些逻辑错误也是至关重要的。

下面我会以简单的登录模块为例，结合具体代码将整个MVP分步来构建，以便更好的去理解MVP，有需要的可以将完整demo去文末clone下来。
1.View–因为是负责页面的显示所以我们要写一个ILoginView的接口内里面写上比如显示进度 应酬进度 登录成功 登录失败用来提示客户

public interface ILoginView {
    void loginSuccess(UserBean userBean);
    void loginFailed(int status, String errorMsg);
}

2.Model–因为model主要是处理数据问题，所以我们要写一个ILoginModel的接口类，写一个登录的抽象方法

public interface ILoginModel {
    //登录
    void toLogin(String username, String password,ResultCallback callback);
}

3.接着我们要写一个Model的实现类，重写Model里面的抽象方法（实现登录的请求）

public class LoginModelImpl implements ILoginModel{

    @Override
    public void toLogin(String username, String password,ResultCallback callback) {
        UserManager.getUserManager().toLogin(username,password,callback);
    }
}

4.Presenter–作为负责处理逻辑，当view和Model写完后我们就应该写Presenter来将view和Model联系起来
首先我们要写一个presenter的接口类，写一个登录的抽象方法实现

public interface ILoginPresenter extends BasePresenter{
    void toLogin(String username, String password);
}

接着我们要写一个presenter的实现类，重写登录方法

public class LoginPresenterImpl extends BasePresenterImpl implements ILoginPresenter {
private ILoginModel loginModel;

public LoginPresenterImpl(ILoginView view) {
    super(view);
    mView = view;
    loginModel = new LoginModelImpl();//这里要注意
}

@Override
public void toLogin(String username, String password) {
    loginModel.toLogin(username, password, new ResultCallback<ResultBean<UBean>>() {
        @Override
        public void onError(int status, String errorMsg) {
             mView.loginFailed( status,  errorMsg);
        }

        @Override
        public void onResponse(ResultBean<UBean> response) {
            UBean uBean=response.getData();
            UserBean userBean=uBean.getUser();

            mView.loginSuccess(userBean);
        }
    });
}}

5.接下来就开始写activity

/**
 * 登录界面
 * Created by wangbin on 16/12/22.
 */

    public class LoginAct extends BaseAct<ILoginPresenter> implements ILoginView {
        @BindView(R.id.login_phone)
        EditText login_phone;
        @BindView(R.id.login_pwd)
        EditText login_pwd;
    
        private String username, pwd;
    
        @Override
        public int getLayout() {
            return R.layout.act_login;
        }
    
        @Override
        public void init(Bundle savedInstanceState) {
            mPresenter = new LoginPresenterImpl(this);
        }
    
        @OnClick({R.id.tv_toRegister, R.id.tv_toForget, R.id.btn_login})
        public void OnClick(View v) {
            switch (v.getId()) {
                case R.id.tv_toRegister://注册
                    AppManager.getAppManager().addActivity(LoginAct.this);
                    openActivity(RegisterAct.class);
                    break;
                case R.id.tv_toForget://忘记密码
                    openActivity(ForgetPwdAct.class);
                    break;
                case R.id.btn_login://登录
                    if (isValidate()) {
                        showProgress("正在登录中...");
                        mPresenter.toLogin(username, pwd);
                    }
                    break;
            }
        }
    
    
        @Override
        public void loginSuccess(UserBean userBean) {
            hideProgress();
            toast("登录成功");
            openActivity(MainAct.class);
    //        sendBroadcast(new Intent(HomeFrg.UPDATA));
            finish();
        }
    
        /**
         * 失败
         *
         * @param status
         * @param errorMsg
         */
        @Override
        public void loginFailed(int status, String errorMsg) {
            hideProgress();
            toast(errorMsg);
        }
    
    
        private boolean isValidate() {
            username = login_phone.getText().toString().trim();
            pwd = login_pwd.getText().toString().toString();
            if (TextUtils.isEmpty(username)) {
                toast("请输入手机号码！");
                login_phone.requestFocus();
                return false;
            }
            if (TextUtils.isEmpty(pwd)) {
                toast("请输入密码!");
                login_pwd.requestFocus();
                return false;
            }
            return true;
        }
    }

Base基类
**

• 基础类

• Created by wangbin on 16/12/22.
  */

  public abstract class BaseAct extends FragmentActivity implements BaseView {
  private TextView tv_title;
  private TextView tvRight;
  private ImageView ivRight;
  private RelativeLayout rl_right;
  private SafeDialog dialog;
  /**
  * 将代理类通用行为抽出来
  */
  protected T mPresenter;

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       // 手机窗口设置无标题
       requestWindowFeature(Window.FEATURE_NO_TITLE);
       setContentView(View.inflate(this, getLayout(), null));
       //注入控件
       ButterKnife.bind(this);
       init(savedInstanceState);
   }
  
   /**
    * 设置布局
    */
   public abstract int getLayout();
  
   /**
    * 填充数据
    */
   public abstract void init(Bundle savedInstanceState);
  
  
   @Override
   protected void onResume() {
       super.onResume();
       if (mPresenter != null) {
           mPresenter.onResume();
       }
   }
  
   @Override
   protected void onDestroy() {
       super.onDestroy();
       if (mPresenter != null) {
           mPresenter.onDestroy();
       }
   }
  
   @Override
   public void toast(String msg) {
       MyToastUtils.showShortToast(getApplicationContext(), msg);
   }
  
   @Override
   public void showProgress(String message) {
       dialog=new SafeDialog(this);
       dialog.setMessage(message);
       dialog.setCancelable(false);
       dialog.show();
   }
  
   @Override
   public void hideProgress() {
       if(dialog!=null){
           dialog.dismiss();
       }
   }
  
   @Override
   public void openActivity(Class<?> pClass) {
       openActivity(pClass, null);
   }
  
   @Override
   public void openActivity(Class<?> pClass, Bundle pBundle) {
       Intent intent = new Intent(this, pClass);
       if (pBundle != null) {
           intent.putExtras(pBundle);
       }
       startActivity(intent);
   }
  
   /**
    * 设置顶部标题
    *
    * @param title
    */
   public void setTopTitle(String title) {
       tv_title = (TextView) findViewById(R.id.tv_title);
       if (title != null) {
           tv_title.setText(title);
       }
   }
  
   /**
    * 顶部右边按键
    *
    * @param rightText
    */
   public void setRightBtn(String rightText, View.OnClickListener listener) {
       tvRight = (TextView) findViewById(R.id.tvRight);
       rl_right = (RelativeLayout) findViewById(R.id.rl_right);
       if (!TextUtils.isEmpty(rightText)) {
           tvRight.setText(rightText);
           rl_right.setVisibility(View.VISIBLE);
           tvRight.setVisibility(View.VISIBLE);
       }
       if (listener != null) {
           rl_right.setOnClickListener(listener);
       }
   }
  
   /**
    * 顶部右边按键(带图片)
    *
    * @param res
    */
   public void setRightBtn(int res, View.OnClickListener listener) {
       ivRight = (ImageView) findViewById(R.id.ivRight);
       rl_right = (RelativeLayout) findViewById(R.id.rl_right);
       rl_right.setVisibility(View.VISIBLE);
       ivRight.setVisibility(View.VISIBLE);
       ivRight.setImageResource(res);
       if (listener != null) {
           rl_right.setOnClickListener(listener);
       }
   }
  
   public void goBack(View view) {
       finish();
   }
  

  }