仿QQ列表ExpandableListView详细写法（通过Java bean封装数据）

下面写一个仿qq列表的二级列表，利用了类体封装，还算比较出色

//主xml写法activity_list_view__main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#edf0f6"
xmlns:tools="http://schemas.android.com/tools">
<ExpandableListView
android:id="@+id/listView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#edf0f6"
>

</ExpandableListView>

</LinearLayout>
接下来是一级列表的写法，我这里为方便布局先做了假数据，后面加载数据源的时候会直接覆盖，文件名first.xml

first.xml

//first.xml<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/first_tv"
android:text="我的好友"
android:layout_marginBottom="15dp"
android:layout_marginLeft="33dp"
android:layout_marginTop="15dp"
android:textColor="@color/nomerName"
android:textSize="22sp"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>

</LinearLayout>

然后是二级列表的布局文件，文件名 list_cell.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">

<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">

<ImageView
android:layout_gravity="center"
android:id="@+id/touXiang"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
/>

<LinearLayout
android:layout_width="wrap_content"
android:layout_height="75dp"
android:orientation="vertical">

<TextView

android:text="中文"
android:textSize="18dp"
android:layout_marginTop="12dp"
android:id="@+id/xinMing"
android:layout_width="wrap_content"
android:layout_height="wrap_content"

4000
android:layout_marginLeft="15dp"

android:textColor="@color/nomerName"/>
<TextView
android:singleLine="true"
android:text="今天天气真好"
android:id="@+id/qianMing"
android:textSize="14dp"
android:layout_marginLeft="15dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/content"

android:paddingTop="3dp"
/>

</LinearLayout>

</LinearLayout>

</LinearLayout>

接下来是Java的内容
先贴JavaBean的封装代码

第一级列表的FirstBean.class

public class FirstBean {
String group;
List<Bean>childBean;

public FirstBean(String group) {
this.group = group;
childBean=new ArrayList<Bean>();
}
public void addChild(Bean bean){
childBean.add(bean);
}
public int getChilidCount(){
return childBean.size();
}

public String getGroup() {
return group;
}
public Bean getChild(int childposition){
return childBean.get(childposition);
}
}

第二级列表的Bean.class

public class Bean {
private int imageView;
private String name,content;

public Bean(int imageView, String name, String content) {
this.imageView = imageView;
this.name = name;
this.content = content;
}

public int getImageView() {
return imageView;
}

public String getName() {
return name;
}

public String getContent() {
return content;
}
}

先贴MyExpandableListAdapter继承自BaseExpandableListAdapter的代码MyExpandableListAdapter.class

package com.example.second_week_listview;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.List;

/**
* Created by Administrator on 2017/9/20.
*/

public class MyExpandListViewAdapter extends BaseExpandableListAdapter {
private Context context;
private List<FirstBean>firstBeanList;
private LayoutInflater mlayoutInflater,layoutInflater;

public MyExpandListViewAdapter(Context context, List<FirstBean> firstBeanList) {
this.context = context;
this.firstBeanList = firstBeanList;
this.mlayoutInflater = LayoutInflater.from(context);
this.layoutInflater=LayoutInflater.from(context);
}

@Override
public int getGroupCount() {
return firstBeanList.size();
}

@Override
public int getChildrenCount(int groupPosition) {
return firstBeanList.get(groupPosition).getChilidCount();
}

@Override
public Object getGroup(int groupPosition) {
return firstBeanList.get(groupPosition);
}

@Override
public Object getChild(int groupPosition, int childPosition) {
return firstBeanList.get(groupPosition).getChild(childPosition);
}

@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}

@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}

@Override
public boolean hasStableIds() {
return false;
}

@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
FirstViewHoder firstViewHoder=null;
if (convertView==null){
firstViewHoder=new FirstViewHoder();
convertView=mlayoutInflater.inflate(R.layout.first,null);
firstViewHoder.textView= (TextView) convertView.findViewById(R.id.first_tv);
convertView.setTag(firstViewHoder);
}
else {
firstViewHoder= (FirstViewHoder) convertView.getTag();
}
FirstBean firstBean=firstBeanList.get(groupPosition);
firstViewHoder.textView.setText(firstBean.getGroup());
return convertView;
}

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
ChildViewHoder childViewHoder=null;
if (convertView==null){
childViewHoder=new ChildViewHoder();
convertView=layoutInflater.inflate(R.layout.list_cell,null);
childViewHoder.ima= (ImageView) convertView.findViewById(R.id.touXiang);
childViewHoder.name= (TextView) convertView.findViewById(R.id.xinMing);
childViewHoder.content= (TextView) convertView.findViewById(R.id.qianMing);
convertView.setTag(childViewHoder);
}
else {
childViewHoder= (ChildViewHoder) convertView.getTag();
}
Bean bean=firstBeanList.get(groupPosition).getChild(childPosition);
childViewHoder.ima.setImageResource(bean.getImageView());
childViewHoder.content.setText(bean.getContent());
childViewHoder.name.setText(bean.getName());
return convertView;
}

@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return false;
}

class FirstViewHoder{
TextView textView;
}
class ChildViewHoder{
ImageView ima;
TextView name,content;
}
}

这里重写了10个必要方法，主要部分在以下两个方面

getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent)

getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent)

groupPosition是第一级点击的位置，childPosition是第二级列表点击的位置，然后其他写法和做了出色封装的BaseAdapter的写法一样，利用viewhoder进行listview优化机制。

下面是主activity的Java代码QQ_main.class

package com.example.second_week_listview;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.widget.ExpandableListView;

import java.util.ArrayList;
import java.util.List;

/**
* Created by Administrator on 2017/9/20.
*/

public class QQ_main extends AppCompatActivity {
private List<FirstBean>firstBeanList=new ArrayList<FirstBean>();
private MyExpandListViewAdapter adapter;
private ExpandableListView listView;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list_view__main);
init();
adapter=new MyExpandListViewAdapter(QQ_main.this,firstBeanList);
listView.setAdapter(adapter);
}

private void init() {
listView= (ExpandableListView) findViewById(R.id.listView);
FirstBean f1=new FirstBean("我的好友");
f1.addChild(new Bean(R.drawable.one,"钟玲","[TIM在线]生活就像一场戏，我希望每天都好。"));
f1.addChild(new Bean(R.drawable.two,"若原","[wifi在线]不愿种花就是不愿意开见花凋零。"));
f1.addChild(new Bean(R.drawable.three,"王欢","[手机在线]我们需要完美！"));
f1.addChild(new Bean(R.drawable.four,"李明","[wifi在线]事无巨细，用心就好。"));
f1.addChild(new Bean(R.drawable.five,"姜晴","[4G在线]早安~ 凉凉的天气~"));
f1.addChild(new Bean(R.drawable.six,"刘艺莲","[wifi在线]徒步，去探寻人生的意义。"));
f1.addChild(new Bean(R.drawable.seven,"欧舒云","[wifi在线]种好你的红豆，别管他人的花生。"));
f1.addChild(new Bean(R.drawable.eight,"海萌","[wifi在线]我有所念人，隔在远远乡。"));
f1.addChild(new Bean(R.drawable.nine,"远路","[4G在线]身残志不残……"));
f1.addChild(new Bean(R.drawable.ten,"雨欣","[手机在线]使我有身后名，不如即时一杯酒。"));
firstBeanList.add(f1);
FirstBean f2=new FirstBean("朋友");
f2.addChild(new Bean(R.drawable.one,"钟玲","[TIM在线]生活就像一场戏，我希望每天都好。"));
f2.addChild(new Bean(R.drawable.two,"若原","[wifi在线]不愿种花就是不愿意开见花凋零。"));
f2.addChild(new Bean(R.drawable.three,"王欢","[手机在线]我们需要完美！"));
f2.addChild(new Bean(R.drawable.four,"李明","[wifi在线]事无巨细，用心就好。"));
f2.addChild(new Bean(R.drawable.five,"姜晴","[4G在线]早安~ 凉凉的天气~"));
f2.addChild(new Bean(R.drawable.six,"刘艺莲","[wifi在线]徒步，去探寻人生的意义。"));
f2.addChild(new Bean(R.drawable.seven,"欧舒云","[wifi在线]种好你的红豆，别管他人的花生。"));
f2.addChild(new Bean(R.drawable.eight,"海萌","[wifi在线]我有所念人，隔在远远乡。"));
f2.addChild(new Bean(R.drawable.nine,"远路","[4G在线]身残志不残……"));
f2.addChild(new Bean(R.drawable.ten,"雨欣","[手机在线]使我有身后名，不如即时一杯酒。"));
firstBeanList.add(f2);
FirstBean f3=new FirstBean("家人");
f3.addChild(new Bean(R.drawable.one,"钟玲","[TIM在线]生活就像一场戏，我希望每天都好。"));
f3.addChild(new Bean(R.drawable.two,"若原","[wifi在线]不愿种花就是不愿意开见花凋零。"));
f3.addChild(new Bean(R.drawable.three,"王欢","[手机在线]我们需要完美！"));
f3.addChild(new Bean(R.drawable.four,"李明","[wifi在线]事无巨细，用心就好。"));
f3.addChild(new Bean(R.drawable.five,"姜晴","[4G在线]早安~ 凉凉的天气~"));
f3.addChild(new Bean(R.drawable.six,"刘艺莲","[wifi在线]徒步，去探寻人生的意义。"));
f3.addChild(new Bean(R.drawable.seven,"欧舒云","[wifi在线]种好你的红豆，别管他人的花生。"));
f3.addChild(new Bean(R.drawable.eight,"海萌","[wifi在线]我有所念人，隔在远远乡。"));
f3.addChild(new Bean(R.drawable.nine,"远路","[4G在线]身残志不残……"));
f3.addChild(new Bean(R.drawable.ten,"雨欣","[手机在线]使我有身后名，不如即时一杯酒。"));
firstBeanList.add(f3);
}
}

下面是用到的图片名称资源