上拉刷新列表（自定义列表项布局）的实现

listView是应用非常广泛的一个控件，当我们要用ListView来自定义列表项，并且从服务器下载数据更新到ListView时，我们通常会新开一个线程进行异步下载，效果图如下：



实现的代码如下：

/**
*  本类用来显示Vip卡的信息
*/
public class ActyMyCard extends Activity implements AbsListView.OnScrollListener{
private ListView listview;
private Thread mThread;
LinearLayout loadingLayout;         //lsitview的页脚布局
private ListViewAdapter adapter ;
private ProgressBar progressBar;
private ImageButton back;
/**
* 设置布局显示属性
*/
private LinearLayout.LayoutParams mLayoutParams = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
/**
* 设置布局显示目标最大化属性
*/
private LinearLayout.LayoutParams FFlayoutParams = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.MATCH_PARENT);

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

init();

}

private void init() {

adapter = new ListViewAdapter(ActyMyCard.this, getData());//设置适配器

listview = (ListView) findViewById(R.id.list_card);

LinearLayout layout = new LinearLayout(this);
layout.setOrientation(LinearLayout.HORIZONTAL);
progressBar = new ProgressBar(this);
progressBar.setPadding(0,0,15,0);
layout.addView(progressBar, mLayoutParams);
TextView tv = new TextView(this);
tv.setText("加载中...");
tv.setGravity(Gravity.CENTER_VERTICAL);
layout.addView(tv, FFlayoutParams);
layout.setGravity(Gravity.CENTER);

//设置listview页脚layout
loadingLayout = new LinearLayout(this);
loadingLayout.addView(layout,mLayoutParams);
loadingLayout.setGravity(Gravity.CENTER);

listview.addFooterView(loadingLayout);
listview.setAdapter(adapter);   //设置适配器
listview.setOnScrollListener(this);

back = (ImageButton) findViewById(R.id.back_card);
back.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
finish();
}
});
}

@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {

}

@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
if(firstVisibleItem+visibleItemCount == totalItemCount){
//开线程下载网络数据
if(mThread == null || !mThread.isAlive()){
mThread = new Thread(){
@Override
public void run() {
//TODO: 这里请求服务器获取卡包信息，然后将信息封装成list,卡包信息封装在类CardMsg中
try{
Thread.sleep(4000);

}catch (InterruptedException e ){
e.printStackTrace();
}
Message message = new Message();
message.what = Config.REFLASHLISTVIEW;
handler.sendMessage(message);
}
};
mThread.start();
}
}
}

private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what){
case Config.REFLASHLISTVIEW:
if(adapter.count <=100){
adapter.count+=10;
int currentPage = adapter.count / 10;
//TODO:这里是把上面封装的list传入adapter
adapter.addList(getData());
Toast.makeText(getApplicationContext(), "第" + currentPage + "页", Toast.LENGTH_LONG).show();
} else {
listview.removeFooterView(loadingLayout);
}

adapter.notifyDataSetChanged();
break;
default:
break;
}
}
};
/*
这个方法是测试用的
*/
public List<Map<String,Object>> getData() {
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
for(int i = 0;i< 10;i++){
Map<String,Object> map = new HashMap<String,Object>();
map.put("cardmsg",new CardMsg("name","location",i));
list.add(map);
}

return list;
}
}

class ListViewAdapter extends BaseAdapter {
int count = 10;
LayoutInflater listContainer;
private List<Map<String, Object>> listItems;
private Context context;

public final class ListItemView  {  //自定义控件集合，即列表项的内容控件
public TextView companyName, location;
public ImageView cardImage;

}

public ListViewAdapter(Context context,List<Map<String, Object>> listItems){
this.context = context;
this.listContainer = LayoutInflater.from(context);

this.listItems = listItems;

}
/*
向listItems中添加新的数据
*/
public void addList(List<Map<String,Object>> newList) {
listItems.addAll(newList);
}
@Override
public int getCount(){
return listItems.size();
}

@Override
public Object getItem(int pos) {
return listItems.get(pos);
}

@Override
public long getItemId(int position) {
return position;
}
/*
* 自宝义列表项时，最重要的就是实现getView方法
*/
@Override
public View getView(int position, View v, ViewGroup parent) {
ListItemView listItemView = null;

if(v==null){
listItemView = new ListItemView();
v = listContainer.inflate(R.layout.list_cell_my_card,null);
//获取控件对象
listItemView.companyName = (TextView) v.findViewById(R.id.com_location_list_cus);
listItemView.location = (TextView) v.findViewById(R.id.com_location_list_cus);
listItemView.cardImage = (ImageView) v.findViewById(R.id.card_image_list_cus);
v.setTag(listItemView);
} else {
listItemView = (ListItemView) v.getTag();
}

//TODO: 获取数据，将listItems里的CardMsg更新到控件中，目前这里是用了三个控件
listItemView.companyName.setText(((CardMsg) listItems.get(position).get("cardmsg")).getCompanyName()+position);
listItemView.location.setText(((CardMsg) listItems.get(position).get("cardmsg")).getLocation()+position);

return v;
}
}

对应的布局文件 layout_my_card 如下

<?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="match_parent"
android:layout_height="90dp"
android:gravity="center_vertical"
android:background="#fff"
android:orientation="horizontal">
<ImageButton
android:id="@+id/back_card"
android:layout_width="@dimen/back_btn_width"
android:layout_height="@dimen/back_btn_width"
android:layout_marginLeft="@dimen/padding_left_custom"
android:background="@drawable/back"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="我的卡包"
android:layout_weight="1"

android:textSize="@dimen/big_text_size"
android:gravity="center" />
<ImageView
android:layout_width="30dp"
android:layout_marginRight="@dimen/padding_left_custom"
android:layout_height="wrap_content"
android:background="@android:color/transparent"
/>
</LinearLayout>
<ListView
android:id="@+id/list_card"
android:layout_width="match_parent"
android:layout_height="match_parent">
</ListView>
</LinearLayout>

下面是列表项的布局

<?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">

<RelativeLayout
android:layout_width="match_parent"
android:layout_height="80dp"
>
<ImageView
android:layout_width="80dp"
android:layout_height="80dp"
android:src="@drawable/default_img"
android:id="@+id/card_image_list_cus" />
<TextView
android:id="@+id/com_name_list_cus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="商家名字"
android:textSize="@dimen/textsize_25_sp"
android:layout_alignParentTop="true"
android:layout_toRightOf="@+id/card_image_list_cus"
android:layout_toEndOf="@+id/card_image_list_cus" />
<TextView
android:id="@+id/com_location_list_cus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingRight="@dimen/padding_left_custom"
android:text="店铺位置"
android:textSize="@dimen/textsize_25_sp"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />

</RelativeLayout>
</LinearLayout>