XListView实现多条目网络数据刷新加载 网络加载图片

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

 pager = findViewById(R.id.viewpager);
 group = findViewById(R.id.group);

 li = new ArrayList< ();
 li.add(new Afragment());
 li.add(new Bfragment());
 li.add(new Cfragment());
 li.add(new Dfragment());

 pager.setAdapter(new FragmentPagerAdapter(getSupportFragmentManager()) {
  @Override
  public Fragment getItem(int position) {
  return li.get(position);
  }

  @Override
  public int getCount() {
  return li.size();
  }
 });

 group.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
  @Override
  public void onCheckedChanged(RadioGroup radioGroup, int i) {

  switch (i){
   case R.id.r1:
   pager.setCurrentItem(0);
   break;
   case R.id.r2:
   pager.setCurrentItem(1);
   break;
   case R.id.r3:
   pager.setCurrentItem(2);
   break;
   case R.id.r4:
   pager.setCurrentItem(3);
   break;
  }
  }
 });

 }

 <?xml version="1.0" encoding="utf-8"? 
 <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:app="http://schemas.android.com/apk/res-auto"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 tools:context=".ui.MainActivity" 
 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical"
  
 <android.support.v4.view.ViewPager
  android:id="@+id/viewpager"
  android:layout_width="match_parent"
  android:layout_height="0dp"
  android:layout_weight="9"
   
 
 </android.support.v4.view.ViewPager 
 
 <RadioGroup
  android:id="@+id/group"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_weight="1"
  android:orientation="horizontal"
   
  <RadioButton
  android:id="@+id/r1"
  android:layout_width="wrap_content"
  android:layout_height="match_parent"
  android:button="@null"
  android:gravity="center"
  android:layout_weight="1"
  android:text="Afrag"/ 
  <RadioButton
  android:id="@+id/r2"
  android:layout_width="wrap_content"
  android:layout_height="match_parent"
  android:button="@null"
  android:gravity="center"
  android:layout_weight="1"
  android:text="Bfrag"/ 
  <RadioButton
  android:id="@+id/r3"
  android:layout_width="wrap_content"
  android:layout_height="match_parent"
  android:button="@null"
  android:gravity="center"
  android:layout_weight="1"
  android:text="Cfrag"/ 
  <RadioButton
  android:id="@+id/r4"
  android:layout_width="wrap_content"
  android:layout_height="match_parent"
  android:button="@null"
  android:gravity="center"
  android:layout_weight="1"
  android:text="Dfrag"/ 
 
 </RadioGroup 
 
 </LinearLayout 
 
</android.support.constraint.ConstraintLayout 

public class Afragment extends Fragment{
private int page=1;
private XListView listView;
private MyBaseAdapter adapter;
ResponseBean responseBean;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = View.inflate(getActivity(), R.layout.afrag, null);
listView = view.findViewById(R.id.xlv);
adapter = new MyBaseAdapter(getLayoutInflater());
listView.setAdapter(adapter);
listView.setPullLoadEnable(true);
listView.setXListViewListener(new XListView.IXListViewListener() {
@Override
public void onRefresh() {
page=0;
loadData(page);
}
@Override
public void onLoadMore() {
loadData(page);
}
});
loadData(page);
return view;
}
private String url =
"http://apis.juhe.cn/cook/query?key=3ec004200a6a2f4cf4774e480c006375&menu=%E8%A5%BF%E7%BA%A2%E6%9F%BF&rn=10&pn=";
private void loadData(int page){
String urlString=url+page;
new AsyncTask<String,Void,List<DataItem  (){
@Override
protected List<DataItem  doInBackground(String... strings) {
try {
URL url = new URL(strings[0]);
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setReadTimeout(5000);
urlConnection.setConnectTimeout(5000);
int responseCode = urlConnection.getResponseCode();
if (responseCode==200){
String result=String2(urlConnection.getInputStream());
responseBean = new Gson().fromJson(result, ResponseBean.class);
}else {
}
return responseBean == null ?null:responseBean.getResult().getData();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(List<DataItem  dataItems) {
super.onPostExecute(dataItems);
if (dataItems == null) {
Toast.makeText(getActivity(), "请求数据错误", Toast.LENGTH_LONG).show();
return;
}
updateData(dataItems);
loadCompleted();
}
}.execute(urlString);
}
private void updateData(List<DataItem  dataItems){
if (page==0){
adapter.setDatas(dataItems);
}else {
adapter.addDatas(dataItems);
}
}
private void loadCompleted(){
page++;
listView.stopRefresh();
listView.stopLoadMore();
}
private String String2(InputStream stream){
StringBuilder sb = new StringBuilder();
BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
try {
for (String tmp=reader.readLine();tmp!=null;tmp=reader.readLine()){
sb.append(tmp);
}
} catch (IOException e) {
e.printStackTrace();
}
return sb.toString();
}
}

public class MyBaseAdapter extends BaseAdapter{
private List<DataItem  datas;
private LayoutInflater layoutInflater;
public MyBaseAdapter(LayoutInflater layoutInflater) {
this.layoutInflater = layoutInflater;
datas=new ArrayList< ();
}
public void setDatas(List<DataItem  datas) {
datas.clear();
if (datas!=null){
datas.addAll(datas);
}
notifyDataSetChanged();
}
public void addDatas(List<DataItem  dataItems) {
if (dataItems!=null){
datas.addAll(dataItems);
notifyDataSetChanged();
}
}
public final int VIEW_TYPE_COUNT=2;
public final int IMAGE_TEXT_TYPE=0;
public final int TEXT_TYPE=1;
@Override
public int getItemViewType(int position) {
if (position % 2==0){
return IMAGE_TEXT_TYPE;
}else {
return TEXT_TYPE;
}
}
@Override
public int getViewTypeCount() {
return VIEW_TYPE_COUNT;
}
@Override
public int getCount() {
return datas.size();
}
@Override
public Object getItem(int i) {
return datas.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int i, View view, ViewGroup viewGroup) {
if (getItemViewType(i)==IMAGE_TEXT_TYPE){
ViewHolder viewHolder=null;
if (view==null){
view = layoutInflater.inflate(R.layout.item, viewGroup,false);
viewHolder = new ViewHolder(view);
}else {
viewHolder = (ViewHolder) view.getTag();
}
viewHolder.bindData((DataItem) getItem(i));
}else {
ViewHolder2 viewHolder2;
if (view==null){
view = layoutInflater.inflate(R.layout.item_text, viewGroup, false);
viewHolder2 = new ViewHolder2();
viewHolder2.textView = view.findViewById(R.id.text);
view.setTag(viewHolder2);
}else {
viewHolder2 = (ViewHolder2) view.getTag();
}
viewHolder2.textView.setText(datas.get(i).getTitle());
}
return view;
}
public class ViewHolder{
private ImageView icon;
private TextView title;
private TextView date;
public ViewHolder(View view) {
icon = view.findViewById(R.id.icon);
title = view.findViewById(R.id.title);
date = view.findViewById(R.id.date);
view.setTag(this);
}
public void bindData(DataItem item) {
title.setText(item.getTitle());
date.setText(item.getId());
ImageLoader.getInstance().displayImage(item.getFirst(),icon
, ImageloaderConfigs.getDefult(icon.getContext()));
}
}
public class ViewHolder2{
TextView textView;
}
}

public class ImageloaderConfigs {
public static ImageLoaderConfiguration getImageLoader(Context context){
ImageLoaderConfiguration configuration = new ImageLoaderConfiguration.Builder(context)
.memoryCacheSizePercentage(13)
.diskCacheSize(50*1024*1024)
.defaultDisplayImageOptions(DisplayImageOptions.createSimple())
.writeDebugLogs()
.build();
return configuration;
}
public static DisplayImageOptions getDefult(Context context){
DisplayImageOptions imageOptions = new DisplayImageOptions.Builder()
.cacheInMemory(true)
.cacheOnDisk(true)
.bitmapConfig(Bitmap.Config.RGB_565)
.imageScaleType(ImageScaleType.EXACTLY_STRETCHED)
.displayer(new CircleBitmapDisplayer())
.build();
return imageOptions;
}
}

public class App extends Application{
@Override
public void onCreate() {
super.onCreate();
ImageLoader.getInstance().init(ImageloaderConfigs.getImageLoader(this));
}
}

public class ResponseBean {
private int resultcode;
private String reason;
private Result result;
public int getResultcode() {
return resultcode;
}
public String getReason() {
return reason;
}
public Result getResult() {
return result;
}
public class Result{
private List<DataItem  data;
public List<DataItem  getData() {
return data;
}
}
}

public class DataItem {
private String id;
private String title;
private List<String  albums;
public String getId() {
return id;
}
public String getTitle() {
return title;
}
public List<String  getAlbums() {
return albums;
}
public String getFirst(){
return albums==null || albums.size()==0? "" : albums.get(0);
}