前言
文本已经收录到我的Github个人博客，欢迎大佬们光临寒舍：我的GIthub博客
看完本篇文章的，可以看下带你封装自己的MVP+Retrofit+RxJava2框架（二），里面封装得到了改进
本篇文章需要已经具备的知识：
MVP的概念和基本使用Retrofit框架的基本使用RxJava2框架的基本使用ButterKnife框架的基本使用Base基类的概念
学习清单：
Activity和Fragment基类的封装MVP的封装使用
一.为什么要封装这套框架呢？
在搞清楚这个问题之前，我们回顾一下基本概念
RxJava: ReactiveX 在JVM上的一个实现，ReactiveX使用Observable序列组合异步和基于事件的程序；掌握了它，你可以优美地处理异步任务和事件的回调
Retrofit:一个 RESTful 的 HTTP网络请求框架的封装，网络请求的工作本质上是OkHttp 完成，而 Retrofit仅负责 网络请求接口的封装:掌握了它，你能优美地进行网络请求。
MVP：一种解耦模型和视图的模式，是现在很多公司的主流模式。
由此可见，在平时的开发中熟练运用这种模式，不仅可以满足生活中大部分应用程序的场景，还可以为将来的工作积攒宝贵的实战经验。
二.核心用法
本项目基于
Android X进行构建，完整代码可在我的Github上下载:带你封装自己的MVP+Retrofit+RxJava2框架
首先，看一下我们项目的基本结构，下面笔者将为大家详细介绍每个类的相关信息
2.1 基类Base
Base基类是封装了一些基类，方便后面新建新的Activity或者Fragment，减少耦合
2.1.1 BaseActivity
这个类是
Activity的基类，注意与下面的BaseMvpActivity区分开
/**
* Description : BaseActivity 基类活动
*
* @author XuCanyou666
* @date 2020/2/2
*/
public abstract class BaseActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(getLayoutId());
initPresenter();
initViews();
ButterKnife.bind(this);
}
/**
* 抽象方法：实例化Presenter
*/
protected abstract void initPresenter();
/**
* 抽象方法：初始化控件，一般在BaseActivity中通过ButterKnife来绑定，所以该方法内部一般我们初始化界面相关的操作
*
* @return 控件
*/
protected abstract void initViews();
/**
* 抽象方法：得到布局id
*
* @return 布局id
*/
protected abstract int getLayoutId();
/**
* 启动Fragment
*
* @param id id
* @param fragment 碎片
*/
protected void startFragment(int id, Fragment fragment) {
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.add(id, fragment);
fragmentTransaction.commit();
}
}
2.1.2 BaseView
一个接口，说明了每一个
View基本需要的一些操作
package com.users.xucanyou666.rxjava2_retrofit_mvp.base;
/**
* created by xucanyou666
* on 2020/1/31 18:26
* email：913710642@qq.com
*/
public interface BaseView {
/**
* 显示进度框
*/
void showProgressDialog();
/**
* 关闭进度框
*/
void hideProgressDialog();
/**
* 出错信息的回调
*
* @param result 错误信息
*/
void onError(String result);
}
2.1.3 BaseMvpActivity
MVP活动的基类继承自
BaseActivity,它是MVP活动的基类，封装好了Presenter的相关操作
package com.users.xucanyou666.rxjava2_retrofit_mvp.base;
/**
* created by xucanyou666 MVP活动的基类，封装好了presenter的相关操作
* on 2019/12/24 20:53
* email：913710642@qq.com
*/
public abstract class BaseMvpActivity<V extends BaseView, P extends BasePresenter> extends BaseActivity {
private P presenter;
/**
* 初始化presenter
*/
@Override
protected void initPresenter() {
presenter = createPresenter();
if (presenter != null) {
presenter.attachView((V) this);
}
}
/**
* 创建presenter
*
* @return Presenter
*/
protected abstract P createPresenter();
/**
* 得到presenter
*
* @return presenter
*/
protected P getPresenter() {
return presenter;
}
/**
* 销毁
*/
@Override
protected void onDestroy() {
super.onDestroy();
if (presenter != null) {
presenter.detachView();
}
}
}
2.1.4 BaseFragment
Fragment的基类需要注意的是，这里用了
ButterKnife框架，对碎片进行了绑定和解绑操作
/**
* Fragment的基类，封装了一些Fragment的相关操作
* created by xucanyou666
* on 2020/1/31 16:21
* email：913710642@qq.com
*/
public abstract class BaseFragment<T extends BasePresenter> extends Fragment implements BaseView {
protected T mPresenter;
protected Context mContext;
protected Bundle mBundle;
protected Unbinder unbinder;
protected View view;
/**
* 恢复数据
*
* @param outState bundle
*/
@Override
public void onSaveInstanceState(@NonNull Bundle outState) {
super.onSaveInstanceState(outState);
if (mBundle != null) {
outState.putBundle("bundle", mBundle);
}
}
/**
* 绑定activity
*
* @param context context
*/
@Override
public void onAttach(@NonNull Context context) {
super.onAttach(context);
mContext = context;
}
/**
* 运行在onAttach之后，可以接收别人传递过来的参数，实例化对象
* 可以解决返回的时候页面空白的bug
*
* @param savedInstanceState
*/
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
mBundle = savedInstanceState.getBundle("bundle");
} else {
mBundle = getArguments() == null ? new Bundle() : getArguments();
}
//初始化presenter
mPresenter = initPresenter();
}
protected T getPresenter() {
return mPresenter;
}
/**
* 运行在onCreate之后，生成View视图
*
* @param inflater
* @param container
* @param savedInstanceState
* @return
*/
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
view = initView(inflater, container, savedInstanceState);
unbinder = ButterKnife.bind(this, view);
return view;
}
/**
* 运行在onCreateView之后
* 加载数据
*
* @param savedInstanceState
*/
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
mPresenter.attachView(this);
}
/**
* 跳转Fragment
*
* @param toFragment 跳转去的fragment
*/
public void startFragment(Fragment toFragment) {
Log.d(TAG, "haha");
startFragment(toFragment, null);
}
/**
* 跳转Fragment
*
* @param toFragment 跳转到的fragment
* @param tag fragment的标签
*/
public void startFragment(Fragment toFragment, String tag) {
FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();
fragmentTransaction.hide(this).add(android.R.id.content, toFragment, tag);
fragmentTransaction.addToBackStack(tag);
fragmentTransaction.commitAllowingStateLoss();
}
@Override
public void onDestroyView() {
super.onDestroyView();
unbinder.unbind();
}
/**
* fragment进行回退
* 类似于activity的OnBackPress
*/
public void onBack() {
getFragmentManager().popBackStack();
}
@Override
public void onDetach() {
mPresenter.detachView();
super.onDetach();
}
/**
* 初始化Fragment应有的视图
*
* @return view
*/
public abstract View initView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState);
/**
* 创建presenter
*
* @return <T extends BasePresenter> 必须是BasePresenter的子类
*/
public abstract T initPresenter();
/**
* 得到context
*
* @return context
*/
@Override
public Context getContext() {
return mContext;
}
/**
* 得到bundle
*
* @return bundle
*/
public Bundle getBundle() {
return mBundle;
}
/**
* 得到fragment
*
* @return fragment
*/
public Fragment getFragment() {
return this;
}
}
2.1.5 BasePresenter
Presenter的基类，
CompositeDisposable主要用途是及时取消订阅，以防止内存泄漏，具体CompositeDisposable的用法可参照Rxjava关于Disposable你应该知道的事
/**
* created by xucanyou666
* on 2020/1/16 17:12
* email：913710642@qq.com
*/
public abstract class BasePresenter<V extends BaseView> {
//将所有正在处理的Subscription都添加到CompositeSubscription中。统一退出的时候注销观察
private CompositeDisposable mCompositeDisposable;
private V baseView;
/**
* 和View绑定
*
* @param baseView
*/
public void attachView(V baseView) {
this.baseView = baseView;
}
/**
* 解绑View,该方法在BaseMvpActivity类中被调用
*/
public void detachView() {
baseView = null;
// 在界面退出等需要解绑观察者的情况下调用此方法统一解绑，防止Rx造成的内存泄漏
if (mCompositeDisposable != null) {
mCompositeDisposable.dispose();
}
}
/**
* 获取View
*
* @return view
*/
public V getMvpView() {
return baseView;
}
/**
* 将Disposable添加,在每次网络访问之前初始化时进行添加操作
*
* @param subscription subscription
*/
public void addDisposable(Disposable subscription) {
//csb 如果解绑了的话添加 sb 需要新的实例否则绑定时无效的
if (mCompositeDisposable == null || mCompositeDisposable.isDisposed()) {
mCompositeDisposable = new CompositeDisposable();
}
mCompositeDisposable.add(subscription);
}
}
2.1.6 MyApplication
- 封装了一个可以全局获取
Context的方法，参考写法自：《第一行代码--第二版》- 注意：记得在
AndroidManifest中注册Application
package com.users.xucanyou666.rxjava2_retrofit_mvp.base;
import android.app.Application;
import android.content.Context;
/**
* 基类
* created by xucanyou666
* on 2019/11/2 14:46
* email：913710642@qq.com
* @author xucanyou666
*/
public class MyApplication extends Application {
private static Context context;
@Override
public void onCreate() {
super.onCreate();
context = getApplicationContext();
}
public static Context getContext() {
return context;
}
}
2.2 工具类 Util
2.2.1 RetrofitManager
Retrofit单例工具类
/**
* Retrofit单例工具类
* created by xucanyou666
* on 2020/1/16 16:38
* email：913710642@qq.com
*/
public class RetrofitManager {
private Retrofit mRetrofit;
//构造器私有，这个工具类只有一个实例
private RetrofitManager() {
OkHttpClient.Builder httpClientBuilder = new OkHttpClient.Builder();
httpClientBuilder.connectTimeout(15, TimeUnit.SECONDS);
mRetrofit = new Retrofit.Builder()
.client(httpClientBuilder.build())
.addConverterFactory(GsonConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.baseUrl(BASE_URL)
.build();
}
/**
* 静态内部类单例模式
*
* @return
*/
public static RetrofitManager getInstance() {
return Inner.retrofitManager;
}
private static class Inner {
private static final RetrofitManager retrofitManager = new RetrofitManager();
}
/**
* 利用泛型传入接口class返回接口实例
*
* @param ser 类
* @param <T> 类的类型
* @return Observable
*/
public <T> T createRs(Class<T> ser) {
return mRetrofit.create(ser);
}
}
2.2.2 RxJavaUtil
RxJava的工具类，执行线程调度工作
/**
* created by xucanyou666
* on 2019/11/17 19:20
* email：913710642@qq.com
*
* @author xucanyou666
*/
public class RxJavaUtil {
/**
* 线程调度工作
*
* @param observable 被观察者
* @param <T> 类型
*/
public static <T> Observable toSubscribe(Observable<T> observable) {
return observable.subscribeOn(Schedulers.io())
.unsubscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread());
}
}
2.3 常量类 Contant
常量池，特别感谢
api open网提供的免费API
/**
* created by xucanyou666
* on 2019/11/17 19:01
* email：913710642@qq.com
*/
public class StaticQuality {
public static final String BASE_URL="https://api.gushi.ci/";
}
2.4 接口管理器 Contract
这里集中了一些
Model层,Presenter层,View层的与诗歌相关的接口
/**
* 诗歌的接口管理器
* created by xucanyou666
* on 2020/2/2 15:33
* email：913710642@qq.com
*/
public interface IPoetryContract {
interface IPoetryModel {
/**
* 得到诗歌
*
* @return 诗歌
*/
Observable<PoetryEntity> getPoetry();
}
interface IPoetryPresenter {
void getPoetry();
}
interface IPoetryView extends BaseView {
/**
* @param author 作者
*/
void searchSuccess(String author);
}
}
2.5 实体类 Entity
/**
* 诗歌的实体类
* created by xucanyou666
* on 2020/1/23 21:23
* email：913710642@qq.com
* API返回示例：
* {
* "content": "胡瓶落膊紫薄汗，碎叶城西秋月团。",
* "origin": "从军行七首",
* "author": "王昌龄",
* "category": "古诗文-天气-月亮"
* }
*/
public class PoetryEntity {
private String content; //诗歌内容
private String origin; //来源
private String author; //作者
private String category; //分类
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
public String getOrigin() {
return origin;
}
public void setOrigin(String origin) {
this.origin = origin;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
}
2.6 Retrofit接口 iApiService
/**
* retrofit接口
* created by xucanyou666
* on 2020/1/23 21:25
* email：913710642@qq.com
*/
public interface GetPoetryEntity {
/**
* 获取古诗词
*
* @return 古诗词
*/
@GET("all.json")
Observable<PoetryEntity> getPoetry();
}
2.7 视图层 View
这里为了减少代码量，方便读者们掌握核心操作，故
View层都是用的同一个Presenter和Model，仅作学习参考
2.7.1 MainActivity
需要注意的是，这里
BaseMvpActivity<activity, presenter>中Activity填入的是当前的Activity，Presenter填入的是对应的Presenter
/**
* Description : MainActivity
*
* @author XuCanyou666
* @date 2020/2/3
*/
public class MainActivity extends BaseMvpActivity<MainActivity, PoetryPresenter> implements IPoetryContract.IPoetryView {
@BindView(R.id.btn_get_poetry)
Button btnGetPoetry;
@BindView(R.id.tv_poetry_author)
TextView tvPoetryAuthor;
@BindView(R.id.btn_goto_fragment)
Button btnGotoFragment;
@BindView(R.id.ll)
LinearLayout ll;
@Override
protected void initViews() {
}
@Override
protected int getLayoutId() {
return R.layout.activity_main;
}
@Override
protected PoetryPresenter createPresenter() {
return PoetryPresenter.getInstance();
}
@Override
public void searchSuccess(String author) {
tvPoetryAuthor.setText(author);
}
@Override
public void showProgressDialog() {
}
@Override
public void hideProgressDialog() {
}
@Override
public void onError(String result) {
Toast.makeText(MyApplication.getContext(), result, Toast.LENGTH_SHORT).show();
}
@OnClick({R.id.btn_get_poetry, R.id.btn_goto_fragment})
public void onViewClicked(View view) {
switch (view.getId()) {
case R.id.btn_get_poetry:
getPresenter().getPoetry();
break;
case R.id.btn_goto_fragment:
startFragment(R.id.ll, new MainFragment());
break;
default:
break;
}
}
}
2.7.2 MainFragment
/**
* Description : MainFragment
*
* @author XuCanyou666
* @date 2020/2/2
*/
public class MainFragment extends BaseFragment<PoetryPresenter> implements IPoetryContract.IPoetryView {
@BindView(R.id.btn_get_poetry)
Button btnGetPoetry;
@BindView(R.id.tv_poetry_author)
TextView tvPoetryAuthor;
@Override
public View initView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_main, container, false);
}
@Override
public PoetryPresenter initPresenter() {
return PoetryPresenter.getInstance();
}
@Override
public void showProgressDialog() {
}
@Override
public void hideProgressDialog() {
}
@Override
public void onError(String result) {
Toast.makeText(MyApplication.getContext(), result, Toast.LENGTH_SHORT).show();
}
@OnClick(R.id.btn_get_poetry)
public void onViewClicked() {
getPresenter().getPoetry();
}
@Override
public void searchSuccess(String author) {
tvPoetryAuthor.setText(author);
}
}
2.8 Presenter层
/**
* created by xucanyou666
* on 2020/1/16 17:09
* email：913710642@qq.com
*/
public class PoetryPresenter extends BasePresenter<IPoetryContract.IPoetryView> implements IPoetryContract.IPoetryPresenter {
private static final String TAG = "PoetryPresenter";
private PoetryEntity mPoetryEntity;
private PoetryModel mPoetryModel;
private PoetryPresenter() {
mPoetryModel = PoetryModel.getInstance();
}
public static PoetryPresenter getInstance() {
return Inner.instance;
}
private static class Inner {
private static final PoetryPresenter instance = new PoetryPresenter();
}
/**
* 得到诗歌
*/
@Override
public void getPoetry() {
Observable observable = mPoetryModel.getPoetry().doOnSubscribe(new Consumer<Disposable>() {
@Override
public void accept(Disposable disposable) throws Exception {
addDisposable(disposable);
}
});
observable = RxJavaUtil.toSubscribe(observable);
observable.subscribe(new Observer<PoetryEntity>() {
@Override
public void onSubscribe(Disposable d) {
}
@Override
public void onNext(PoetryEntity poetryEntity) {
mPoetryEntity = poetryEntity;
}
@Override
public void onError(Throwable e) {
getMvpView().onError(e.getMessage());
Log.d(TAG, "onError: " + e.getMessage());
}
@Override
public void onComplete() {
if (mPoetryEntity != null) {
getMvpView().searchSuccess(mPoetryEntity.getAuthor());
}
}
});
}
}
2.9 Model层
/**
* created by xucanyou666
* on 2020/1/16 17:06
* email：913710642@qq.com
*/
public class PoetryModel implements IPoetryContract.IPoetryModel {
private PoetryModel() {
}
public static PoetryModel getInstance() {
return Inner.instance;
}
private static class Inner {
private static final PoetryModel instance = new PoetryModel();
}
/**
* 获取古诗词
*
* @return 古诗词
*/
@Override
public Observable<PoetryEntity> getPoetry() {
return RetrofitManager.getInstance().createRs(GetPoetryEntity.class).getPoetry();
}
}
2.10 app.build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 28
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
defaultConfig {
applicationId "com.users.xucanyou666.rxjava2_retrofit_mvp"
minSdkVersion 19
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
// RxJava
implementation 'io.reactivex.rxjava2:rxjava:2.1.12'
implementation 'com.squareup.retrofit2:retrofit:2.6.0'
// Retrofit和jxjava关联
implementation 'com.squareup.retrofit2:adapter-rxjava2:2.4.0'
// Retrofit使用Gson转换
implementation 'com.squareup.retrofit2:converter-gson:2.4.0'
// RxAndroid
implementation 'io.reactivex.rxjava2:rxandroid:2.0.2'
//引入ButterKnife
implementation "com.jakewharton:butterknife:10.2.0"
implementation 'androidx.legacy:legacy-support-v4:1.0.0'
annotationProcessor "com.jakewharton:butterknife-compiler:10.2.0"
implementation "com.google.android.material:material:1.0.0"
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
}
三.我在使用中遇到的问题
3.1 网络权限忘记授予
- 解决措施：加上权限即可
<uses-permission android:name="android.permission.INTERNET" />
3.2 ButterKnife框架版本问题
使用ButterKnife框架的时候
当是androidX的时候，需要implementation 10.2.0版本的ButterKnife
//引入ButterKnife
implementation "com.jakewharton:butterknife:10.2.0"
implementation 'androidx.legacy:legacy-support-v4:1.0.0'
annotationProcessor "com.jakewharton:butterknife-compiler:10.2.0"
当是android 28等其他版本的时候，可以导入8.4.0版本的ButterKnife（导入10.2.0版本会出错）
implementation 'com.jakewharton:butterknife:8.4.0'
annotationProcessor 'com.jakewharton:butterknife-compiler:8.4.0'
3.3 ButterKnife需要Java 1.8以上的支持
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
3.4 Fragment中点击事件失效的问题
- 点击事件失效发生的场景：
Fragment中初始化控件没有用ButterKnife框架
解决措施如下：
A:方法一:
- 将控件的初始化放在
onCreateView中 - 将控件的点击事件的代码放在
onActivityCreated中
B:方法二：
- 在
Fragment中使用ButterKnife框架
如果文章对您有一点帮助的话，希望您能点一下赞，您的点赞，是我前进的动力
本文参考链接：
-
《第一行代码》
来源：oschina
链接：https://my.oschina.net/u/4400756/blog/4185303