正文
Android 给双ListView组织数据源
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需求：现有这样一套原始数据{“A”,"B","C","D","B","A","B","C","A","B","D","D"}.
要求将此数据组织成为双列表形式显示，即将元素相同的数据分为一组，即{["A","A","A"],["B","B","B","B"],["C","C"],["D","D","D"]}并将分组后的数据显示在ListView界面上。（外部ListView显示每一组，内部ListView显示每一组中的组成员）
以下是需求效果展示图：
第一步：组织数据源（这一步也是我认为的最重要的一部，剩下的都是数据显示的问题，相信大家都会的，呵呵）
1.过滤数据（筛选出不重复数据）
2.将重复数据分别放入不同的集合中（小集合）
3.将重复数据集合放到大集合中（用于存放小集合）
4.代码展示：
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;/**
* 组织双列表的数据源
* @author yw-tony
*
*/
public class TwoListViewDataTools {
private TwoListViewDataTools(){}
private static TwoListViewDataTools instance;
public static TwoListViewDataTools getInstance(){
synchronized (TwoListViewDataTools.class) {
if(instance == null){
instance = new TwoListViewDataTools();
}
}
return instance;
}
/**
* 根据分组标记找出每一种元素在集合中的个数，并组织成为一个个的集合，然后存入共同的大集合中
* @param data原始数据
* @return
*/
public List<List<String>> listToGroup(List<String> data){
//最终集合的展现形式
List<List<String>> largeGroup = new ArrayList<List<String>>();
//筛选后的集合，此集合中存放的是原始集合中的不重复元素
List<String> diff = getListDifferentElement(data);
for(int i=0;i<diff.size();i++){//筛选后的集合
List<String> littleGroup = new ArrayList<String>();
for(int j= 0;j<data.size();j++){//原始集合
//如果遇到相同元素就存入元素集合中
if(diff.get(i).equals(data.get(j))){
littleGroup.add(data.get(j));
}
}
largeGroup.add(littleGroup);
}
return largeGroup;
}
/**
* 获取一个集合中不同元素的集合
* @param data 演示数据
*/
private List<String> getListDifferentElement(List<String> data){
//使用set集合可以过滤掉集合中的重复元素
Set<String> sets = new HashSet<String>();
List<String> diff = new ArrayList<String>();
for(int i=0;i<data.size();i++){
sets.add(data.get(i));
}
for(String s : sets){
diff.add(s);
}
return diff;
}
}
第二部：给列表填充数据（仅作代码展示，主要功能都加上了注释）
import java.util.ArrayList;
import java.util.List;import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.MarginLayoutParams;
import android.widget.BaseAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;import com.yw.myapiupdate.R;/**
* 显示数据的主Activity类
* @author yw-tony
*
*/
public class ListViewTwoActivity extends Activity{
//分组后的集合
private List<List<String>> group = new ArrayList<List<String>>();
//原始数据集合
private List<String> datas = new ArrayList<String>();
private ListView lv_main;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.lv_two_main);
/*初始化数据源*/
TwoListData.getInstance().addData(datas);
//给集合列表赋值
group = TwoListViewDataTools.getInstance().listToGroup(datas);
/*填充数据源*/
lv_main = (ListView)findViewById(R.id.lv_two_main_lv);
MainBaseAdapter adapter = new MainBaseAdapter(this);
adapter.setList(group);
lv_main.setAdapter(adapter);
//动态的计算列表的高度
setListViewHeightBasedOnChildren(lv_main);
}
/**
* 外层baseadapter
* @author yw-tony
*
*/
class MainBaseAdapter extends BaseAdapter{
private Context context;
private LayoutInflater inflater;
private List<List<String>> baseGroup = new ArrayList<List<String>>();
public MainBaseAdapter(Context context){
this.context = context;
this.inflater = LayoutInflater.from(context);
}
public void setList(List<List<String>> baseGroup){
this.baseGroup = baseGroup;
}
@Override
public int getCount() {
return baseGroup.size();
} @Override
public Object getItem(int arg0) {
return baseGroup.get(arg0);
} @Override
public long getItemId(int arg0) {
return arg0;
} @Override
public View getView(int arg0, View view, ViewGroup arg2) {
if(view == null){
view = inflater.inflate(R.layout.lv_two_main_item, null);
}
ListView lv_item = (ListView)view.findViewById(R.id.lv_two_main_item);
List<String> items = baseGroup.get(arg0);
//设置子listview的数据源，并显示出来
ItemBaseAdapter itemAdapter = new ItemBaseAdapter(ListViewTwoActivity.this);
itemAdapter.setList(items);
lv_item.setAdapter(itemAdapter);
//设置内层数据列表的高度
setListViewHeightBasedOnChildren(lv_item);
return view;
} }
/**
* 子（内层）listview的数据源
* @author yw-tony
*
*/
class ItemBaseAdapter extends BaseAdapter{
private Context context;
private LayoutInflater inflater;
private List<String> items = new ArrayList<String>();
public ItemBaseAdapter(Context context){
this.context = context;
this.inflater = LayoutInflater.from(context);
}
public void setList(List<String> items){
this.items = items;
}
@Override
public int getCount() {
return items.size();
} @Override
public Object getItem(int position) {
return items.get(position);
} @Override
public long getItemId(int position) {
return position;
} @Override
public View getView(int position, View convertView, ViewGroup parent) {
if(convertView == null){
convertView = inflater.inflate(R.layout.lv_two_item_item, null);
}
TextView tv = (TextView)convertView.findViewById(R.id.lv_two_item_item_tv);
tv.setText(items.get(position));
return convertView;
} }
/**动态改变listView的高度*/
public void setListViewHeightBasedOnChildren(ListView listView) {
ListAdapter listAdapter = listView.getAdapter();
if (listAdapter == null) {
return;
}
int totalHeight = 0;
for (int i = 0; i < listAdapter.getCount(); i++) {
View listItem = listAdapter.getView(i, null, listView);
listItem.measure(0, 0);
totalHeight += listItem.getMeasuredHeight();
// totalHeight += 80;
}
ViewGroup.LayoutParams params = listView.getLayoutParams();
// params.height = 80 * (listAdapter.getCount() - 1);
// params.height = 80 * (listAdapter.getCount());
params.height = totalHeight
+ (listView.getDividerHeight() * (listAdapter.getCount() - 1));
((MarginLayoutParams) params).setMargins(0, 0, 0, 0);
listView.setLayoutParams(params); }
}
下面提出数据源（元数据）
import java.util.List;
/**
* 模拟从网络上获取到的数据源
* @author yw-tony
*
*/
public class TwoListData {
private TwoListData(){}
private static TwoListData instance;
public static TwoListData getInstance(){
synchronized (TwoListData.class) {
if(instance == null){
instance = new TwoListData();
}
}
return instance;
}
/**
* 添加模拟数据
*/
public void addData(List<String> data){
data.add("A");
data.add("B");
data.add("C");
data.add("B");
data.add("A");
data.add("C");
data.add("A");
data.add("B");
data.add("A");
}}
以下给出配置文件信息
1.主文件：
<?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="#ff0000"
android:orientation="vertical" >
<ListView
android:id="@+id/lv_two_main_lv"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
></ListView></LinearLayout>
2.主文件的item
<?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" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#00ffff"
android:gravity="center"
>
<ListView
android:id="@+id/lv_two_main_item"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
></ListView>
</LinearLayout></LinearLayout>
3.item的item
<?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/lv_two_item_item_tv"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:text="测试"
android:textSize="25sp"
android:background="#33ffcc"/></LinearLayout>
运行后的展示效果图：
