VLayoutDemo【VLayout的简单使用demo（基于V1.2.8版本）】

前言

VirtualLayout是一个针对RecyclerView的LayoutManager扩展, 主要提供一整套布局方案和布局间的组件复用的问题。

设计思路

通过定制化的LayoutManager，接管整个RecyclerView的布局逻辑；LayoutManager管理了一系列LayoutHelper，LayoutHelper负责具体布局逻辑实现的地方；每一个LayoutHelper负责页面某一个范围内的组件布局；不同的LayoutHelper可以做不同的布局逻辑，因此可以在一个RecyclerView页面里提供异构的布局结构，这就能比系统自带的LinearLayoutManager、GridLayoutManager等提供更加丰富的能力。同时支持扩展LayoutHelper来提供更多的布局能力。

主要功能

默认通用布局实现，解耦所有的View和布局之间的关系: Linear, Grid, 吸顶, 浮动, 固定位置等。
- LinearLayoutHelper: 线性布局
- GridLayoutHelper: Grid布局，支持横向的colspan
- FixLayoutHelper: 固定布局，始终在屏幕固定位置显示
- ScrollFixLayoutHelper: 固定布局，但之后当页面滑动到该图片区域才显示, 可以用来做返回顶部或其他书签等
- FloatLayoutHelper: 浮动布局，可以固定显示在屏幕上，但用户可以拖拽其位置
- ColumnLayoutHelper: 栏格布局，都布局在一排，可以配置不同列之间的宽度比值
- SingleLayoutHelper: 通栏布局，只会显示一个组件View
- OnePlusNLayoutHelper: 一拖N布局，可以配置1-5个子元素
- StickyLayoutHelper: stikcy布局，可以配置吸顶或者吸底
- StaggeredGridLayoutHelper: 瀑布流布局，可配置间隔高度/宽度
上述默认实现里可以大致分为两类：一是非fix类型布局，像线性、Grid、栏格等，它们的特点是布局在整个页面流里，随页面滚动而滚动；另一类就是fix类型的布局，它们的子节点往往不随页面滚动而滚动。
所有除布局外的组件复用，VirtualLayout将用来管理大的模块布局组合，扩展了RecyclerView，使得同一RecyclerView内的组件可以复用，减少View的创建和销毁过程。

使用

这个demo只是简单记录下上面黄色标记的几种布局的实现。

注意

vlayout1.2.8版本中使用的recyclerview是23.1.1版本，v4是23.1.1，这个需要注意。如果项目中用到recyclerview和v4包的话，建议依赖新版本的recyclerview和v4。

下面是vlayout的build.gradle文件的部分源码：

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    // compile project(':extension')
    if (project.hasProperty('useNewSupportLibrary')) {
        compile 'com.android.support:recyclerview-v7:25.2.0@aar'
        compile('com.android.support:support-v4:25.2.0@aar')
        compile 'com.android.support:support-annotations:25.2.0'
        compile 'com.android.support:support-compat:25.2.0'
        compile 'com.android.support:support-core-ui:25.2.0'
    } else {
        compile 'com.android.support:recyclerview-v7:23.1.1@aar'
        compile('com.android.support:support-v4:23.1.1@aar') {
            exclude group: 'com.android.support', module: 'support-annotations'
        }
        compile 'com.android.support:support-annotations:23.1.1'
    }

    androidTestCompile "org.robolectric:robolectric:3.0"
}

所以在项目中app目录的build.gradle中依赖vlayout时，会有这样的提醒：

效果图

使用步骤

一、项目组织结构图

注意事项：

1、导入类文件后需要change包名以及重新import R文件路径

2、 Values目录下的文件（strings.xml、dimens.xml、colors.xml等），如果项目中存在，则复制里面的内容，不要整个覆盖

二、导入步骤

1、在build.gradle文件中依赖vlayout

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.why.project.vlayoutdemo"
        minSdkVersion 16
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

    //Vlayout
    implementation ('com.alibaba.android:vlayout:1.2.8@aar') {
        transitive = true
    }
    //下面的代码，根据实际情况添加，如果项目中用到了下面的库，则需要根据项目依赖高版本库，否则就会使用vlayout中的低版本库
    //RecyclerView【因为vlayout中的recyclerview版本低，所以需要重新依赖高版本，否则app中使用recyclerview的话会直接使用vlayout中的低版本recyclerview】
    implementation "com.android.support:recyclerview-v7:28.0.0"
    //v4
    implementation 'com.android.support:support-v4:28.0.0'
}

这样就将vlayout集成到项目中了。

三、使用方法

1、先在demo中添加测试数据文件

{
    "data": [
        {
            "modelname": "推送新闻",
            "data": [
                {
                    "image": "https://imgsa.baidu.com/news/q%3D100/sign=06d12a2732dbb6fd235be1263925aba6/b151f8198618367a8dbfe10125738bd4b31ce53c.jpg",
                    "url": "http://news.ifeng.com/a/20180120/55302258_0.shtml?_zbs_baidu_news",
                    "title": "安徽合肥：“非遗”进校园",
                    "id": "whyidzhi",
                    "order": "1"
                }
            ]
        },
        {
            "modelname": "焦点新闻",
            "data": [
                {
                    "image": "https://b.bdstatic.com/boxlib/20180120/2018012017100383423448679.jpg",
                    "url": "http://pic.chinadaily.com.cn/2018-01/20/content_35544757.htm",
                    "title": "西昌铁路警方用表情包宣传爱路小知识",
                    "id": "whyidzhi",
                    "order": "1"
                },
                {
                    "image": "https://b.bdstatic.com/boxlib/20180120/2018012017100311270281486.jpg",
                    "url": "http://pic.chinadaily.com.cn/2018-01/20/content_35544758.htm",
                    "title": "成都熊猫基地太阳产房全新升级",
                    "id": "whyidzhi",
                    "order": "2"
                },
                {
                    "image": "https://b.bdstatic.com/boxlib/20180120/2018012017100392134086973.jpg",
                    "url": "http://pic.chinadaily.com.cn/2018-01/20/content_35544759.htm",
                    "title": "长沙“90后”交警用手绘记录交警故事",
                    "id": "whyidzhi",
                    "order": "3"
                }
            ]
        },
        {
            "modelname": "国际人物",
            "data": [
                {
                    "image": "http://t12.baidu.com/it/u=264843290,870648681&fm=173&s=29C043870E531CDC082897A003006015&w=218&h=146&img.JPEG",
                    "url": "http://news.163.com/18/0120/15/D8JS570V00018AOQ_all_mobile.html",
                    "title": "法总统马克龙会见默克尔 强调欧洲改革需要德国（全文..",
                    "id": "whyidzhi",
                    "order": "1"
                },
                {
                    "image": "",
                    "url": "http://www.yidianzixun.com/article/0IBPUBcu",
                    "title": "默克尔组阁能否成功？全等这场党代会",
                    "id": "whyidzhi",
                    "order": "2"
                },
                {
                    "image": "",
                    "url": "http://www.yidianzixun.com/article/0IBMT9yr",
                    "title": "马克龙向默克尔表支持 强调推动欧洲改革需要德国",
                    "id": "whyidzhi",
                    "order": "3"
                },
                {
                    "image": "",
                    "url": "http://news.sina.com.cn/w/2018-01-20/doc-ifyquixe4989529.shtml",
                    "title": "德法首脑在巴黎会晤 默克尔：欧洲需要稳定的德国政府",
                    "id": "whyidzhi",
                    "order": "4"
                },
                {
                    "image": "",
                    "url": "http://news.sina.com.cn/o/2018-01-20/doc-ifyqtycx0664636.shtml",
                    "title": "德国社民党民众支持率创新低",
                    "id": "whyidzhi",
                    "order": "5"
                }
            ]
        },
        {
            "modelname": "图片新闻",
            "data": [
                {
                    "image": "https://t10.baidu.com/it/u=44207055,3448633405&fm=173&s=CFF20CC150452CEC9F9C491103005092&w=218&h=146&img.JPEG",
                    "url": "http://war.163.com/18/0120/11/D8JEFM5D000181KT_mobile.html",
                    "title": "外媒称朝鲜先遣队取消访韩",
                    "id": "whyidzhi",
                    "order": "1"
                },
                {
                    "image": "https://t10.baidu.com/it/u=1625316837,2876937793&fm=173&s=F507703317115D6644753AE80300E036&w=218&h=146&img.JPEG",
                    "url": "http://news.china.com/internationalgd/10000166/20180120/31985304.html",
                    "title": "狂风横扫欧洲多国，致10人",
                    "id": "whyidzhi",
                    "order": "2"
                },
                {
                    "image": "https://t10.baidu.com/it/u=2946973968,4057971581&fm=173&s=2D216D93C2F00B9219A825E703009060&w=218&h=146&img.JPEG",
                    "url": "http://news.sina.com.cn/w/2018-01-20/doc-ifyqtycx0654102.shtml",
                    "title": "津巴布韦反对党要人在美坠",
                    "id": "whyidzhi",
                    "order": "3"
                },
                {
                    "image": "https://t12.baidu.com/it/u=3788697896,2880168169&fm=173&s=D31A38C4D664D55FC29281010300309B&w=218&h=146&img.JPEG",
                    "url": "http://finance.ifeng.com/a/20180120/15937975_0.shtml",
                    "title": "美国政府关门 比特币闻讯",
                    "id": "whyidzhi",
                    "order": "4"
                },
                {
                    "image": "https://t10.baidu.com/it/u=1499851317,895362806&fm=173&s=BD04DF104871339C53A88C870100E0E3&w=218&h=146&img.JPEG",
                    "url": "http://news.sina.com.cn/o/2018-01-20/doc-ifyquixe5136803.shtml",
                    "title": "刚刚，美国政府正式宣告",
                    "id": "whyidzhi",
                    "order": "5"
                },
                {
                    "image": "https://t12.baidu.com/it/u=4229963978,641890755&fm=173&s=74B218D646A08B491AAF3E9903001088&w=218&h=146&img.JPEG",
                    "url": "http://www.chinanews.com/gj/2018/01-20/8428898.shtml",
                    "title": "超三成受访者称中国是“新",
                    "id": "whyidzhi",
                    "order": "6"
                }
            ]
        },
        {
            "modelname": "视频新闻",
            "data": [
                {
                    "image": "http://pic.rmb.bdstatic.com/1f01839d477aa7a3ffa36f07542f8d5b.jpg@h_660,w_370",
                    "url": "http://v.qq.com/x/page/h0527p90e2b.html",
                    "title": "杭州餐馆爆炸，路过公交车20余人受伤",
                    "id": "whyidzhi",
                    "order": "1"
                },
                {
                    "image": "http://pic.rmb.bdstatic.com/1f541422405ab18797795c0adc3318eb.jpg@h_660,w_370",
                    "url": "http://www.iqiyi.com/v_19rr7omigs.html",
                    "title": "中央措辞严厉批祁连山生态问题 8责任人被问责",
                    "id": "whyidzhi",
                    "order": "2"
                },
                {
                    "image": "http://pic.rmb.bdstatic.com/d46f662c1900de051da6de2eef2c485f.jpg@h_660,w_370",
                    "url": "http://v.qq.com/x/page/a0024q7bkg0.html",
                    "title": "吉林永吉 吉林市多地遭暴雨袭击 县城灾后清理正在进行",
                    "id": "whyidzhi",
                    "order": "3"
                },
                {
                    "image": "http://pic.rmb.bdstatic.com/b9cdfca4adeb36ac1a0730f70b9d63f9.jpg@h_660,w_370",
                    "url": "http://www.iqiyi.com/v_19rr7oosfs.html",
                    "title": "40 高温下一出租车行驶中自燃",
                    "id": "whyidzhi",
                    "order": "4"
                },
                {
                    "image": "http://pic.rmb.bdstatic.com/660e5152b144e48bbdffdad5d9fdc088.jpg@h_660,w_370",
                    "url": "http://v.qq.com/x/page/v0527bhjwh3.html",
                    "title": "徐光裕：印度航母只是二流航母",
                    "id": "whyidzhi",
                    "order": "5"
                }
            ]
        }
    ]
}

vlayout.txt

2、因为Demo中使用到了banner和图片展现，所以还需要依赖banner和glide

参考《BannerDemo【图片轮播图控件】》、《GlideNewDemo【Glide4.7.1版本的简单使用以及圆角功能】》

3、在布局文件声明Recyclerview控件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    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"
    android:orientation="vertical">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/vlayout_rv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scrollbars="none"
        android:clipToPadding="true"
        android:paddingLeft="0dp"
        android:paddingRight="0dp"
        android:requiresFadingEdge="none"/>

</LinearLayout>

4、在Acitivity中参考下面的代码编写基本框架（也就是逻辑处理）

package com.why.project.vlayoutdemo;

import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.widget.Toast;

import com.alibaba.android.vlayout.DelegateAdapter;
import com.alibaba.android.vlayout.VirtualLayoutManager;
import com.alibaba.android.vlayout.layout.GridLayoutHelper;
import com.alibaba.android.vlayout.layout.LinearLayoutHelper;
import com.alibaba.android.vlayout.layout.SingleLayoutHelper;
import com.alibaba.android.vlayout.layout.StickyLayoutHelper;
import com.why.project.vlayoutdemo.adapter.BannerLayoutAdapter;
import com.why.project.vlayoutdemo.adapter.GridLayoutAdapter;
import com.why.project.vlayoutdemo.adapter.HorizontalListLayoutAdapter;
import com.why.project.vlayoutdemo.adapter.ListLayoutAdapter;
import com.why.project.vlayoutdemo.adapter.StickyTitleAdapter;
import com.why.project.vlayoutdemo.bean.ItemBean;
import com.why.project.vlayoutdemo.bean.ModelBean;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private static final String TAG = MainActivity.class.getSimpleName();

    private List<ModelBean> mModelBeanList;//列表数据集合

    private RecyclerView mVLayoutRV;

    private VirtualLayoutManager layoutManager;
    private DelegateAdapter delegateAdapter;
    private List<DelegateAdapter.Adapter> adapters;

    private RecyclerView.RecycledViewPool viewPool;//设置复用池的大小
    private int itemType;//一个Adapter对应一个类型，这里通过自增加1实现唯一性

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

        initViews();
        initDatas();
    }

    private void initViews() {
        mVLayoutRV = findViewById(R.id.vlayout_rv);
    }

    private void initDatas() {
        //初始化列表数据集合
        mModelBeanList = new ArrayList<ModelBean>();
        getTestDatas();
        Log.e(TAG,"mModelBeanList.size()=" + mModelBeanList.size());


        //初始化LayoutManager
        layoutManager = new VirtualLayoutManager(this);
        layoutManager.setRecycleOffset(300);
        mVLayoutRV.setLayoutManager(layoutManager);

        //设置回收复用池大小，（如果一屏内相同类型的 View 个数比较多，需要设置一个合适的大小，防止来回滚动时重新创建 View）
        //针对type=0的item设置了复用池的大小，如果你的页面有多种type，需要为每一种类型的分别调整复用池大小参数。
        viewPool = new RecyclerView.RecycledViewPool();
        mVLayoutRV.setRecycledViewPool(viewPool);

        //加载数据，通过创建adapter集合实现布局
        delegateAdapter = new DelegateAdapter(layoutManager, false);//必须使用false，实现每一个分组的类型不同
        mVLayoutRV.setAdapter(delegateAdapter);

        setVLayoutAdapter();
    }

    /**设置适配器*/
    private void setVLayoutAdapter() {

        itemType = 0;//自增加1
        if (adapters != null) {
            adapters.clear();
        } else {
            adapters = new LinkedList<>();
        }

        //根据类型不同，采用不同的adapter并添加到集合中
        for(int i=0; i<mModelBeanList.size(); i++){
            String modelName = mModelBeanList.get(i).getModelName();
            String type = mModelBeanList.get(i).getType();
            ArrayList<ItemBean> itemBeanArrayList = (ArrayList<ItemBean>) mModelBeanList.get(i).getItemDataList();

            boolean showModelName = true;//控制是否显示model，也就是吸顶布局
            if(showModelName){
                //stikcy布局， 可以配置吸顶或者吸底
                //设置各个区域的复用池的大小，因为只有一个元素，所以复用池大小就设置为1
                viewPool.setMaxRecycledViews(itemType++, 1);
                StickyLayoutHelper stickyLayoutHelper = new StickyLayoutHelper();
                StickyTitleAdapter stickyTitleAdapter = new StickyTitleAdapter(this,stickyLayoutHelper,modelName);
                adapters.add(stickyTitleAdapter);
            }

            //========用来判断分组，展现不同的样式========
            //每一个item对应一种样式
            switch(type) {
                case "banner":
                    //通栏布局——轮播图
                    //设置各个区域的复用池的大小，设置子集合的总个数为复用池大小
                    viewPool.setMaxRecycledViews(itemType++, itemBeanArrayList.size());
                    SingleLayoutHelper singleLayoutHelper = new SingleLayoutHelper();//通栏布局，只会显示一个组件View
                    singleLayoutHelper.setMargin(0, 0, 0, dip2px(this, 10));//设置外边距，实现分割效果
                    BannerLayoutAdapter bannerLayoutAdapter = new BannerLayoutAdapter(this, singleLayoutHelper, itemBeanArrayList);
                    bannerLayoutAdapter.setBannerCallback(new BannerLayoutAdapter.BannerCallback() {
                        @Override
                        public void clickBanner(ItemBean itemBean) {
                            Toast.makeText(MainActivity.this,itemBean.getTitle(),Toast.LENGTH_SHORT).show();
                        }
                    });//设置自定义回调，用于点击事件监听
                    adapters.add(bannerLayoutAdapter);
                    break;
                case "hori":
                    //通栏布局——横向列表
                    //设置各个区域的复用池的大小，设置子集合的总个数为复用池大小
                    viewPool.setMaxRecycledViews(itemType++, itemBeanArrayList.size());
                    SingleLayoutHelper horizontalListLayoutHelper = new SingleLayoutHelper();//不使用LinearLayoutHelper
                    horizontalListLayoutHelper.setMargin(0,0,0,dip2px(this, 10));//设置外边距，实现分割效果
                    HorizontalListLayoutAdapter horizontalListLayoutAdapter = new HorizontalListLayoutAdapter(this,horizontalListLayoutHelper,itemBeanArrayList);
                    horizontalListLayoutAdapter.setHorizontalListCallback(new HorizontalListLayoutAdapter.HorizontalListCallback() {
                        @Override
                        public void clickHorizontalItem(ItemBean itemBean) {
                            Toast.makeText(MainActivity.this,itemBean.getTitle(),Toast.LENGTH_SHORT).show();
                        }
                    });//设置自定义回调，用于点击事件监听
                    adapters.add(horizontalListLayoutAdapter);
                    break;
                case "grid":
                    //九宫格布局
                    //设置各个区域的复用池的大小，设置子集合的总个数为复用池大小
                    viewPool.setMaxRecycledViews(itemType++, itemBeanArrayList.size());
                    GridLayoutHelper gridlayoutHelper = new GridLayoutHelper(2);//Grid布局， 支持横向的colspan
                    gridlayoutHelper.setAutoExpand(false);//解决单数的时候，最后一张居中显示的问题
                    gridlayoutHelper.setMargin(0, 0, 0, dip2px(this, 10));//设置外边距，实现分割效果
                    GridLayoutAdapter gridLayoutAdapter = new GridLayoutAdapter(this, gridlayoutHelper, itemBeanArrayList, itemBeanArrayList.size());
                    //设置自定义回调，用于点击事件监听
                    gridLayoutAdapter.setGridCallback(new GridLayoutAdapter.GridCallback() {
                        @Override
                        public void clickGrid(ItemBean itemBean) {
                            Toast.makeText(MainActivity.this,itemBean.getTitle(),Toast.LENGTH_SHORT).show();
                        }
                    });
                    adapters.add(gridLayoutAdapter);
                    break;
                case "list":
                    //列表布局（默认布局）
                    //设置各个区域的复用池的大小，设置子集合的总个数为复用池大小
                    viewPool.setMaxRecycledViews(itemType++, itemBeanArrayList.size());
                    LinearLayoutHelper linearLayoutHelper = new LinearLayoutHelper();//线性布局
                    linearLayoutHelper.setMargin(0, 0, 0, dip2px(this, 10));//设置外边距，实现分割效果
                    ListLayoutAdapter listLayoutAdapter = new ListLayoutAdapter(this, linearLayoutHelper, itemBeanArrayList, itemBeanArrayList.size());
                    //设置自定义回调，用于点击事件监听
                    listLayoutAdapter.setListCallback(new ListLayoutAdapter.ListCallback() {
                        @Override
                        public void clickList(ItemBean itemBean) {
                            Toast.makeText(MainActivity.this,itemBean.getTitle(),Toast.LENGTH_SHORT).show();
                        }
                    });
                    adapters.add(listLayoutAdapter);
                    break;
                default:
            }

        }

        delegateAdapter.setAdapters(adapters);
    }

    /**
     * dp转px
     * 16dp - 48px
     * 17dp - 51px*/
    public static int dip2px(Context context, float dpValue) {
        float scale = context.getResources().getDisplayMetrics().density;
        return (int)((dpValue * scale) + 0.5f);
    }


    /*=======================================获取测试数据==============================================*/
    private void getTestDatas(){
        String listdata = getStringFromAssert(MainActivity.this,"vlayout.txt");
        try {
            JSONObject listObj = new JSONObject(listdata);
            JSONArray listArray = listObj.getJSONArray("data");
            for(int i=0; i< listArray.length(); i++){
                JSONObject itemObj = listArray.getJSONObject(i);

                ModelBean modelBean = new ModelBean();
                modelBean.setModelName(itemObj.getString("modelname"));
                modelBean.setType(itemObj.getString("type"));

                JSONArray childArray = itemObj.getJSONArray("data");
                List<ItemBean> itemBeanList = new ArrayList<ItemBean>();
                for(int j=0; j<childArray.length(); j++){
                    JSONObject childObj = childArray.getJSONObject(j);

                    ItemBean itemBean = new ItemBean();
                    itemBean.setId(childObj.getString("id"));
                    itemBean.setImageUrl(childObj.getString("image"));
                    itemBean.setOrder(childObj.getString("order"));
                    itemBean.setTitle(childObj.getString("title"));
                    itemBean.setUrlPath(childObj.getString("url"));

                    itemBeanList.add(itemBean);
                }

                modelBean.setItemDataList(itemBeanList);

                mModelBeanList.add(modelBean);
            }

        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

    /**
     * 访问assets目录下的资源文件，获取文件中的字符串
     * @param assetsFilePath - 文件的相对路径，例如："listitemdata.txt或者"/why/listdata.txt"
     * @return 内容字符串
     * */
    public static String getStringFromAssert(Context mContext, String assetsFilePath) {

        String content = ""; // 结果字符串
        try {
            InputStream is = mContext.getResources().getAssets().open(assetsFilePath);// 打开文件
            int ch = 0;
            ByteArrayOutputStream out = new ByteArrayOutputStream(); // 实现了一个输出流
            while ((ch = is.read()) != -1) {
                out.write(ch); // 将指定的字节写入此 byte 数组输出流
            }
            byte[] buff = out.toByteArray();// 以 byte 数组的形式返回此输出流的当前内容
            out.close(); // 关闭流
            is.close(); // 关闭流
            content = new String(buff, "UTF-8"); // 设置字符串编码
        } catch (Exception e) {
            Toast.makeText(mContext, "对不起，没有找到指定文件！", Toast.LENGTH_SHORT)
                    .show();
        }
        return content;
    }

}

5、添加各种adapter和布局文件

混淆配置

#Vlayout
-keepattributes InnerClasses
-keep class com.alibaba.android.vlayout.ExposeLinearLayoutManagerEx { *; }
-keep class android.support.v7.widget.RecyclerView$LayoutParams { *; }
-keep class android.support.v7.widget.RecyclerView$ViewHolder { *; }
-keep class android.support.v7.widget.ChildHelper { *; }
-keep class android.support.v7.widget.ChildHelper$Bucket { *; }
-keep class android.support.v7.widget.RecyclerView$LayoutManager { *; }

参考资料

项目demo下载地址

https://github.com/haiyuKing/VLayoutDemo

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原文地址：https://www.cnblogs.com/whycxb/p/9748752.html