Android ExpandableListView实例Demo

前几篇文章介绍了Listview。但在实际开发中也常常会用到多层的Listview来展示数据，比方qq中的好友展示，所以这张来了解一下ExpandableListview。基本思想与Listview大致是同样的。所以用起来会比較方便。

实现效果图：

程序代码：

布局文件：

activity_main.xml：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <ExpandableListView
        android:id="@+id/expandableListView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >
    </ExpandableListView>

</RelativeLayout>

group和child共同使用的布局(当然也能够使用不同的布局来实现)。这的布局比較简单，仅仅有一个Textview：

list_item:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >


    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />


</RelativeLayout>

MainActivity：

package com.listviewdemo_expandablelistview;

import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.widget.ExpandableListView;

public class MainActivity extends Activity {
  private ExpandableListView listView;
  private List<String> group;
  private List<List<String>> child;
  private MyAdapter adapter;

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

    listView = (ExpandableListView) findViewById(R.id.expandableListView);
    /**
     * 初始化数据 
     */
    initData();
    adapter = new MyAdapter(this,group,child);
    listView.setAdapter(adapter);

  }

  private void initData() {
    group = new ArrayList<String>();
    child = new ArrayList<List<String>>();
    addInfo("北京",new String[]{"朝阳","海淀","东城区","西城区"});
    addInfo("河北", new String[]{"邯郸","石家庄","邢台"});
    addInfo("广东", new String[]{"广州","深圳","珠海"});
  }

  /**
   * 加入数据信息
   * @param g
   * @param c
   */
  private void addInfo(String g,String[] c) {
    group.add(g);
    List<String> list = new ArrayList<String>();
    for (int i = 0; i < c.length; i++) {
      list.add(c[i]);
    }
    child.add(list);
  }

}

MyAdapter：

package com.listviewdemo_expandablelistview;

import java.util.List;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.TextView;
/**
 * expandableListView适配器
 *
 */
public class MyAdapter extends BaseExpandableListAdapter {
  private Context context;
  private List<String> group;
  private List<List<String>> child;

  public MyAdapter(Context context, List<String> group,
      List<List<String>> child) {
    this.context = context;
    this.group = group;
    this.child = child;
  }

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

  @Override
  public int getChildrenCount(int groupPosition) {
    return child.size();
  }

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

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

  /**
   * 显示：group
   */
  @Override
  public View getGroupView(int groupPosition, boolean isExpanded,
      View convertView, ViewGroup parent) {
    ViewHolder holder;
    if (convertView == null) {
      convertView = LayoutInflater.from(context).inflate(
          R.layout.list_item, null);
      holder = new ViewHolder();
      holder.textView = (TextView) convertView
          .findViewById(R.id.textView);
      convertView.setTag(holder);
    } else {
      holder = (ViewHolder) convertView.getTag();
    }
    holder.textView.setText(group.get(groupPosition));
    holder.textView.setTextSize(25);
    holder.textView.setPadding(36, 10, 0, 10);
    return convertView;

  }

  /**
   * 显示：child
   */
  @Override
  public View getChildView(int groupPosition, int childPosition,
      boolean isLastChild, View convertView, ViewGroup parent) {
    ViewHolder holder;
    if (convertView == null) {
      convertView = LayoutInflater.from(context).inflate(
          R.layout.list_item, null);
      holder = new ViewHolder();
      holder.textView = (TextView) convertView
          .findViewById(R.id.textView);
      convertView.setTag(holder);
    } else {
      holder = (ViewHolder) convertView.getTag();
    }
    holder.textView.setText(child.get(groupPosition).get(childPosition));
    holder.textView.setTextSize(20);
    holder.textView.setPadding(72, 10, 0, 10);
    return convertView;
  }

  class ViewHolder {
    TextView textView;
  }

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

}

如今博客中增加链接须要审核后才干发表。所以须要源代码的能够到我上传的资源中查找。