Android 结构之MVP

mvp 作为Android 开发中一种典型的架构模式，其优点不言而且，代码逻辑清晰，易扩展，解耦性强，如果封装的号，后期版本迭代，界面ui变化，会很方便。但是，如果写的不好，则会又内存泄漏的风险！本分的目的就是封装一个没有内存泄漏的mvp架构模式

BasePresenter

添加弱引用的支持，防止内存泄漏

import java.lang.ref.WeakReference;

/**
 * Copyright (C), 2015-2019, 北京xxxxxx有限公司
 * Author:
 * Date: 2019/8/27 20:15
 * Description:
 */
public class BasePresenter<T> {

    private WeakReference<T> mViewRef;
    protected BaseActivity activity;

    public void attachView(T view) {
        mViewRef = new WeakReference<>(view);
    }

    public BasePresenter(BaseActivity activity) {
        this.activity = activity;
    }

    protected T getView() {
        if (mViewRef != null) {
            return mViewRef.get();
        } else {
            return null;
        }
    }

    public boolean isViewAttach() {
        return getView() != null;
    }

    protected void detachView() {
        if (mViewRef != null) {
            mViewRef.clear();
            mViewRef = null;
        }
    }
}

BaseActivity

BaseActivity 的封装

import android.os.Bundle;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

/**
 * Copyright (C), 2015-2019, 北京xxxxxx有限公司
 * Author:
 * Date: 2019/8/27 20:20
 * Description:
 */
public abstract class BaseActivity<V, T extends BasePresenter<V>> extends AppCompatActivity {

    protected T presenter;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(initLayout());

        presenter = createPresenter();
        initView();

        if (presenter!=null){
            presenter.attachView((V) this);
        }
    }

    protected abstract void initView();

    protected abstract T createPresenter();

    protected abstract int initLayout();

    @Override
    protected void onDestroy() {
        super.onDestroy();
        presenter.detachView();
    }
}

ok,封装基本完成，开始使用，以登录为例，先看项目结构

/**
 * Copyright (C), 2015-2019, 北京xxxxx有限公司
 * Author:
 * Date: 2019/8/27 20:25
 * Description:
 */
public interface LoginContract {
    interface Model {
    }

    interface View {
        void onSuccess();

        void onFailed(String reason);
    }

    interface Presenter {
        void login(String userName, String passWord);
    }
}


...


import com.sunkaisens.androidutils.base.BaseActivity;
import com.sunkaisens.androidutils.base.BasePresenter;
import com.sunkaisens.app.contract.LoginContract;

/**
 * Copyright (C), 2015-2019, 北京xxxxxxx有限公司
 * Author:
 * Date: 2019/8/27 20:25
 * Description:
 */
public class LoginPresenter extends BasePresenter<LoginContract.View>implements LoginContract.Presenter {


    public LoginPresenter(BaseActivity activity) {
        super(activity);
    }

    @Override
    public void login(String userName, String passWord) {

        if ("sunjianyun".equals(userName)&&"123456".equals(passWord)){
            getView().onSuccess();
        }else {
            getView().onFailed("用户名或密码错误");
        }
    }
}


...

/**
 * Copyright (C), 2015-2019, 北京视游互动科技有限公司
 * Author: sunjianyun
 * Date: 2019/8/27 20:24
 * Description:
 */
public class LoginActivity extends BaseActivity<LoginContract.View, LoginPresenter> implements LoginContract.View {
    @Override
    protected void initView() {

    }

    @Override
    protected LoginPresenter createPresenter() {
        return new LoginPresenter(this);
    }

    @Override
    protected int initLayout() {
        return R.layout.activity_login;
    }

    @Override
    public void onSuccess() {

        ToastUtil.showToast("登录成功");
    }

    @Override
    public void onFailed(String reason) {
        ToastUtil.showToast("登录失败："+reason);

    }

    public void login(View view) {
        presenter.login("sunjianyun","123456");
    }
}