public class MainActivity extends Activity { ???protected static final int WHAT_REQUEST_SUCCESS = 1; ???protected static final int WHAT_REQUEST_ERROR = 2; ???private ListView lv_main; ???private LinearLayout ll_main_loading; ???private List<ShopInfo> data; ???private ShopInfoAdapter adapter; ???private Handler handler = new Handler(){ ???????public void handleMessage(android.os.Message msg) { ???????????switch (msg.what) { ???????????case WHAT_REQUEST_SUCCESS: ???????????????ll_main_loading.setVisibility(View.GONE); ???????????????//显示列表 ???????????????lv_main.setAdapter(adapter); ???????????????break; ???????????case WHAT_REQUEST_ERROR: ???????????????ll_main_loading.setVisibility(View.GONE); ???????????????Toast.makeText(MainActivity.this, "加载数据失败", Toast.LENGTH_SHORT).show(); ???????????????break; ???????????default: ???????????????break; ???????????} ???????} ???}; ???@Override ???protected void onCreate(Bundle savedInstanceState) { ???????super.onCreate(savedInstanceState); ???????setContentView(R.layout.activity_main); ???????????????lv_main = (ListView) findViewById(R.id.lv_main); ???????ll_main_loading = (LinearLayout) findViewById(R.id.ll_main_loading); ???????adapter = new ShopInfoAdapter(); ???????????????//1. 主线程, 显示提示视图 ???????ll_main_loading.setVisibility(View.VISIBLE); ???????//2. 分线程, 联网请求 ???????//启动分线程请求服务器动态加载数据并显示 ???????new Thread(){ ???????????public void run() { ???????????????//联网请求得到jsonString ???????????????try { ???????????????????String jsonString = requestJson(); ???????????????????//解析成List<ShopInfo> ???????????????????data = new Gson().fromJson(jsonString, new TypeToken<List<ShopInfo>>(){}.getType()); ???????????????????//3. 主线程, 更新界面 ???????????????????handler.sendEmptyMessage(WHAT_REQUEST_SUCCESS);//发请求成功的消息 ???????????????} catch (Exception e) { ???????????????????e.printStackTrace(); ???????????????????handler.sendEmptyMessage(WHAT_REQUEST_ERROR);//发送请求失败的消息 ???????????????} ???????????} ???????}.start(); ???????????????????} ???????/** ????* 联网请求得到jsonString ????* @return ????* @throws Exception ?????*/ ???private String requestJson() throws Exception { ???????String result = null; ???????String path = "http://192.168.10.165:8080/L05_Web/ShopInfoListServlet"; ???????//1. 得到连接对象 ???????URL url = new URL(path); ???????HttpURLConnection connection = (HttpURLConnection) url.openConnection(); ???????//2. 设置 ???????connection.setConnectTimeout(5000); ???????connection.setReadTimeout(5000); ???????//连接 ???????connection.connect(); ???????//发请求并读取服务器返回的数据 ???????int responseCode = connection.getResponseCode(); ???????if(responseCode==200) { ???????????InputStream is = connection.getInputStream(); ???????????ByteArrayOutputStream baos = new ByteArrayOutputStream(); ???????????byte[] buffer = new byte[1024]; ???????????int len = -1; ???????????while ((len = is.read(buffer)) != -1) { ???????????????baos.write(buffer, 0, len); ???????????} ???????????baos.close(); ???????????is.close(); ???????????connection.disconnect(); ???????????????????????result = baos.toString(); ???????} else { ???????????//也可以抛出运行时异常 ???????} ???????return result; ???} ???class ShopInfoAdapter extends BaseAdapter { ???????private ImageLoader imageLoader; ???????????????public ShopInfoAdapter() { ???????????imageLoader = new ImageLoader(MainActivity.this, R.drawable.loading, R.drawable.error); ???????} ???????@Override ???????public int getCount() { ???????????return data.size(); ???????} ???????@Override ???????public Object getItem(int position) { ???????????return data.get(position); ???????} ???????@Override ???????public long getItemId(int position) { ???????????return 0; ???????} ???????@Override ???????public View getView(int position, View convertView, ViewGroup parent) { ???????????if(convertView==null) { ???????????????convertView = View.inflate(MainActivity.this, R.layout.item_main, null); ???????????} ???????????//得到当前行的数据对象 ???????????ShopInfo shopInfo = data.get(position); ???????????//得到当前行的子View ???????????TextView nameTV = (TextView) convertView.findViewById(R.id.tv_item_name); ???????????TextView priceTV = (TextView) convertView.findViewById(R.id.tv_item_price); ???????????ImageView imageView = (ImageView) convertView.findViewById(R.id.iv_item_icon); ???????????//设置数据 ???????????nameTV.setText(shopInfo.getName()); ???????????priceTV.setText(shopInfo.getPrice()+"元"); ???????????String imagePath = shopInfo.getImagePath(); ???????????//根据图片路径启动分线程动态请求服务加载图片并显示 ???????????imageLoader.loadImage(imagePath, imageView); ???????????return convertView; ???????} ???????????}}<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" ???android:layout_width="fill_parent" ???android:layout_height="fill_parent" > ???<ListView ???????android:id="@+id/lv_main" ???????android:layout_width="match_parent" ???????android:layout_height="match_parent" > ???</ListView> ???<LinearLayout ???????android:id="@+id/ll_main_loading" ???????android:layout_width="match_parent" ???????android:layout_height="match_parent" ???????android:orientation="vertical" ????????android:gravity="center" ???????android:visibility="gone"> ???????<ProgressBar ???????????style="?android:attr/progressBarStyleLarge" ???????????android:layout_width="wrap_content" ???????????android:layout_height="wrap_content" /> ???????<TextView ???????????android:layout_width="wrap_content" ???????????android:layout_height="wrap_content" ???????????android:text="正在加载中..." /> ???</LinearLayout></FrameLayout>
<?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="60dp" ???android:orientation="horizontal" > ???<ImageView ???????android:id="@+id/iv_item_icon" ???????android:layout_width="60dp" ???????android:layout_height="60dp" ???????android:src="@drawable/ic_launcher"/> ???<LinearLayout ???????android:layout_width="fill_parent" ???????android:layout_height="match_parent" ???????android:orientation="vertical" ????????android:gravity="center_vertical" ???????android:layout_marginLeft="10dp"> ???????<TextView ???????????android:id="@+id/tv_item_name" ???????????android:layout_width="wrap_content" ???????????android:layout_height="wrap_content" ???????????android:text="名称" ????????????android:textSize="18sp"/> ???????????????<TextView ???????????android:id="@+id/tv_item_price" ???????????android:layout_width="wrap_content" ???????????android:layout_height="wrap_content" ???????????android:text="内容" ????????????android:textSize="18sp"/> ???</LinearLayout></LinearLayout>
远程请求json数据，list中显示
原文地址：https://www.cnblogs.com/znsongshu/p/9350079.html