ExpandableListView的简单例子

最近一段时间参考网上的例子，做了一下简单的 ExpandableListView，现在和大家共享一下：

1：main.xml的内容

[html] view
plaincopy

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout

xmlns:android="http://schemas.android.com/apk/res/android"

android:id="@+id/linearLayout"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

androidrientation="vertical"

>

<ExpandableListView

android:id="@+id/expandableListView"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

/>

</LinearLayout>

显示一个ExpandableListView

2：ExpandableListViewDemo 类的内容

[java] view
plaincopy

package com.chama.expandablelistviewdemo;

import java.util.ArrayList;

import java.util.List;

import android.app.Activity;

import android.os.Bundle;

import android.view.Gravity;

import android.view.View;

import android.view.ViewGroup;

import android.widget.AbsListView;

import android.widget.BaseExpandableListAdapter;

import android.widget.ExpandableListView;

import android.widget.TextView;

public class ExpandableListViewDemo extends Activity {

//定义两个List，用来存放控件中Group/Child中的String

private List<String> groupArray;

private List<List<String>> childArray;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

//对这两个List进行初始化，并插入一些数据

groupArray = new ArrayList<String>();

childArray = new ArrayList<List<String>>();

groupArray.add("第一行");

groupArray.add("第二行");

List<String> tempArray = new ArrayList<String>();

tempArray.add("第一条");

tempArray.add("第二条");

tempArray.add("第三条");

for(int index = 0; index <groupArray.size(); ++index)

{

childArray.add(tempArray);

}

//给定义好的ExpandableListView添加上Adapter

ExpandableListView expandableListView = (ExpandableListView)findViewById(R.id.expandableListView);

ExpandableAdapter adapter = new ExpandableAdapter(this);

expandableListView.setAdapter(adapter);

}

//定义ExpandableListView的Adapter

public class ExpandableAdapter extends BaseExpandableListAdapter

{

Activity activity;

public ExpandableAdapter(Activity a)

{

activity = a;

}

public Object getChild(int groupPosition, int childPosition)

{

return childArray.get(groupPosition).get(childPosition);

}

public long getChildId(int groupPosition, int childPosition)

{

return childPosition;

}

public int getChildrenCount(int groupPosition)

{

return childArray.get(groupPosition).size();

}

public View getChildView(int groupPosition, int childPosition,

boolean isLastChild, View convertView, ViewGroup parent)

{

String string = childArray.get(groupPosition).get(childPosition);

return getGenericView(string);

}

// group method stub

public Object getGroup(int groupPosition)

{

return groupArray.get(groupPosition);

}

public int getGroupCount()

{

return groupArray.size();

}

public long getGroupId(int groupPosition)

{

return groupPosition;

}

public View getGroupView(int groupPosition, boolean isExpanded,

View convertView, ViewGroup parent)

{

String string = groupArray.get(groupPosition);

return getGenericView(string);

}

// View stub to create Group/Children 's View

public TextView getGenericView(String string)

{

// Layout parameters for the ExpandableListView

AbsListView.LayoutParams layoutParams = new AbsListView.LayoutParams(

ViewGroup.LayoutParams.FILL_PARENT, 64);

TextView text = new TextView(activity);

text.setLayoutParams(layoutParams);

// Center the text vertically

text.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);

// Set the text starting position

text.setPadding(36, 0, 0, 0);

text.setText(string);

return text;

}

public boolean hasStableIds()

{

return false;

}

public boolean isChildSelectable(int groupPosition, int childPosition)

{

return true;

}

}

}

需要注意的内容：

1：groupArray 和childArray的内容，分别定义父对象和子对象显示的内容

2：ExpandableAdapter继承了BaseExpandableListAdapter，并重载了其中的一些方法， 注意public TextView getGenericView(String string)的作用，主要用形成显示父对象和子对象视图的类

3：程序效果