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：
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程序代码：
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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CSDN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。
本文转自mfrbuaa博客园博客，原文链接：http://www.cnblogs.com/mfrbuaa/p/5302755.html，如需转载请自行联系原作者
