【架构】整理了一份通用的MVP框架示例代码

       最近回顾了一下MVP框架，结合阅读到的几篇不错的博客，自己整理了一份可用于实际工作的MVP框架示例代码，这里做个记录，也顺便和网友们分享一下。

       代码示例演示的是一个输入员工号查询员工信息并显示的场景，查询后的界面如下：

 本文以该场景举例来搭建一个可以通用的MVP架构，代码整体结构如下：

具体的代码及结构说明：

mvpbase：所有MVP业务通用的方法

BaseModel.java

package com.song.mvpdemo.mvpbase.model;

import java.util.Map;

/**
 * 该类抽象出不同业务获取数据的通用方法
 */
public abstract class BaseModel<T> {
    //数据请求参数
    protected String[] mParams;

    /**
     * 设置数据请求参数
     *
     * @param args 参数数组
     */
    public BaseModel params(String... args) {
        mParams = args;
        return this;
    }

    /**
     * 添加Callback并执行数据请求，具体的数据请求由子类实现
     */
    public abstract void execute(ModelCallback<T> modelCallback);

    /**
     * 执行Get网络请求，此类看需求由自己选择写与不写
     */
    public void requestGetApi(String url, ModelCallback<T> modelCallback) {
        //这里写具体的网络请求
    }

    //执行Post网络请求，此类看需求由自己选择写与不写
    public void requestPostApi(String url, Map params, ModelCallback<T> modelCallback) {
        //这里写具体的网络请求
    }
}

ModelCallback.java

package com.song.mvpdemo.mvpbase.model;

/**
 * Presenter层调用Model层后数据回调
 */
public interface ModelCallback<T> {
    void onSuccess(T result);

    void onFailOrError();

    void onCompleted();
}

DataModel.java

package com.song.mvpdemo.mvpbase.model;

/**
 * 该类用于创建具体的业务Model
 */
public class DataModel {
    public static BaseModel createModel(Class clazz) {
        BaseModel model = null;
        try {
            model = (BaseModel) clazz.newInstance();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        }
        return model;
    }
}

BasePresenter.java

package com.song.mvpdemo.mvpbase.presenter;

import com.song.mvpdemo.mvpbase.view.IBaseView;

/**
 * 不同业务Presenter层通用的操作
 */
public class BasePresenter<V extends IBaseView> {
    private V mView;

    public void attachView(V baseView) {
        mView = baseView;
    }

    public void dettachView() {
        mView = null;
    }

    public boolean isViewAttached() {
        return mView != null;
    }

    public V getView() {
        return mView;
    }
}

IBaseView.java

package com.song.mvpdemo.mvpbase.view;

public interface IBaseView {
    void showLoading();

    void hideLoading();

    void showFailOrError(String msg);
}

BaseActivity.java

package com.song.mvpdemo.mvpbase.view;

import android.app.ProgressDialog;
import android.os.Bundle;

import androidx.appcompat.app.AppCompatActivity;

import com.song.mvpdemo.mvpbase.presenter.BasePresenter;

public abstract class BaseActivity extends AppCompatActivity implements IBaseView {

    private ProgressDialog mProgressDialog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        initPresenter();
        if (getPresenter() != null) {
            getPresenter().attachView(this);
        }

        mProgressDialog = new ProgressDialog(this);
        mProgressDialog.setCancelable(false);
        mProgressDialog.setMessage("Loading...");
    }

    @Override
    public void showLoading() {
        if (mProgressDialog != null && !mProgressDialog.isShowing()) {
            mProgressDialog.show();
        }
    }

    @Override
    public void hideLoading() {
        if (mProgressDialog != null && mProgressDialog.isShowing()) {
            mProgressDialog.dismiss();
        }
    }

    /**
     * 初始化Presenter的实例，子类实现
     */
    protected abstract void initPresenter();

    /**
     * 获取Presenter实例，子类实现
     */
    protected abstract BasePresenter getPresenter();

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (getPresenter() != null) {
            getPresenter().dettachView();
        }
    }
}

StaffInfo.java

package com.song.mvpdemo.staffinfo.model;

public class StaffInfo {
    private String staffId;
    private String name;
    private int age;
    private float salary;

    public StaffInfo(String staffId, String name, int age, float salary) {
        this.staffId = staffId;
        this.name = name;
        this.age = age;
        this.salary = salary;
    }

    public String getStaffId() {
        return staffId;
    }

    public void setStaffId(String staffId) {
        this.staffId = staffId;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public float getSalary() {
        return salary;
    }

    public void setSalary(float salary) {
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "StaffInfo{" +
                "staffId='" + staffId + '\'' +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", salary=" + salary +
                '}';
    }
}

StaffInfoDataModel.java

package com.song.mvpdemo.staffinfo.model;

import android.os.Handler;

import com.song.mvpdemo.mvpbase.model.BaseModel;
import com.song.mvpdemo.mvpbase.model.ModelCallback;

public class StaffInfoDataModel extends BaseModel<StaffInfo> {

    @Override
    public void execute(ModelCallback<StaffInfo> modelCallback) {
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                switch (mParams[0]) {
                    case ""://输入的staffid为空，则显示失败
                        modelCallback.onFailOrError();
                        break;
                    default:
                        StaffInfo staffInfo = new StaffInfo(mParams[0], "张三", 20, 20000);
                        modelCallback.onSuccess(staffInfo);
                        break;
                }
                modelCallback.onCompleted();
            }
        }, 5000);
    }
}

StaffInfoPresenter.java

package com.song.mvpdemo.staffinfo.presenter;

import com.song.mvpdemo.mvpbase.presenter.BasePresenter;
import com.song.mvpdemo.mvpbase.model.DataModel;
import com.song.mvpdemo.mvpbase.model.ModelCallback;
import com.song.mvpdemo.staffinfo.model.StaffInfo;
import com.song.mvpdemo.staffinfo.model.StaffInfoDataModel;
import com.song.mvpdemo.staffinfo.view.IStaffInfoView;

public class StaffInfoPresenter extends BasePresenter<IStaffInfoView> {

    public void queryStaffInfo(String param) {
        getView().showLoading();

        DataModel.createModel(StaffInfoDataModel.class)
                .params(param)
                .execute(new ModelCallback<StaffInfo>() {
                    @Override
                    public void onSuccess(StaffInfo result) {
                        if (isViewAttached()) {
                            getView().showStaffInfo(result);
                        }
                    }

                    @Override
                    public void onFailOrError() {
                        if (isViewAttached()) {
                            getView().showFailOrError("fail");
                        }
                    }

                    @Override
                    public void onCompleted() {
                        if (isViewAttached()) {
                            getView().hideLoading();
                        }
                    }
                });
    }
}

IStaffInfoView.java

package com.song.mvpdemo.staffinfo.view;

import com.song.mvpdemo.mvpbase.view.IBaseView;
import com.song.mvpdemo.staffinfo.model.StaffInfo;

public interface IStaffInfoView extends IBaseView {
    /**
     * 具体业务特有的方法，无法做为通用的方法提取出来
     */
    String getStaffId();

    void showStaffInfo(StaffInfo staffInfo);

    void clearStaffId();
}

StaffInfoActivity.java

package com.song.mvpdemo.staffinfo.view;

import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

import com.song.mvpdemo.mvpbase.view.BaseActivity;
import com.song.mvpdemo.mvpbase.presenter.BasePresenter;
import com.song.mvpdemo.R;
import com.song.mvpdemo.staffinfo.presenter.StaffInfoPresenter;
import com.song.mvpdemo.staffinfo.model.StaffInfo;

public class StaffInfoActivity extends BaseActivity implements IStaffInfoView {
    private TextView mStaffInfoTv;
    private EditText mStaffIdEt;
    private StaffInfoPresenter mStaffInfoPresenter;

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

    private void initView() {
        mStaffInfoTv = findViewById(R.id.tv_result);
        mStaffIdEt = findViewById(R.id.staffId_et);
        findViewById(R.id.btn_submit).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mStaffInfoPresenter.queryStaffInfo(getStaffId());
            }
        });

        findViewById(R.id.btn_clear).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                clearStaffId();
            }
        });
    }


    @Override
    protected void initPresenter() {
        mStaffInfoPresenter = new StaffInfoPresenter();
    }

    @Override
    protected BasePresenter getPresenter() {
        return mStaffInfoPresenter;
    }

    @Override
    public void showFailOrError(String msg) {
        mStaffInfoTv.setText(msg);
    }

    @Override
    public String getStaffId() {
        return mStaffIdEt.getText().toString();
    }

    @Override
    public void showStaffInfo(StaffInfo staffInfo) {
        mStaffInfoTv.setText(staffInfo.toString());
    }

    @Override
    public void clearStaffId() {
        mStaffIdEt.setText("");
    }
}

activity_staffinfo.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=".staffinfo.view.StaffInfoActivity">

    <TextView
        android:id="@+id/tv_result"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="50dp"
        android:text=""
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/staffId_et"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:hint="input staff id"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/tv_result" />


    <Button
        android:id="@+id/btn_submit"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="50dp"
        android:text="submit"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/staffId_et" />

    <Button
        android:id="@+id/btn_clear"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:text="clear"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/btn_submit" />

</androidx.constraintlayout.widget.ConstraintLayout>

参考：

Android MVP升级路（一）乞丐版的自我救赎

Android MVP升级路（二）轻项目标配之时尚版

Android MVP升级路（三）随心所欲的旗舰版

浅谈 MVP in Android