1，http请求，将paramList发送到http://api.renren.com/restserver.do进行post请求。
同时得到HttpResponse响应，判断响应代码是否为200，为200表示成功。解析JSON数据为相关对象。
private String sendRequest() { String returnValue = "0"; httpClient = new DefaultHttpClient(); try { HttpPost httpPost = new HttpPost( "http://api.renren.com/restserver.do"); httpPost.setEntity(new UrlEncodedFormEntity(paramList, HTTP.UTF_8));// 添加请求参数到请求对象 HttpResponse httpResponse = httpClient.execute(httpPost); if (httpResponse.getStatusLine().getStatusCode() == 200) { // 为200表示执行成功 strResult = EntityUtils.toString(httpResponse.getEntity()); // 得到返回数据（为JSON数据） Log.i("RenrenFriendsActivity", "strResult:" + strResult); if (!strResult.contains("error_code")) { renrenList = RenrenUtil.parseRenrenFromJson(strResult); // 解析JSON数据为相应对象 returnValue = "1"; // 定义返回标志 } } } catch (ClientProtocolException e) { strResult = e.getMessage().toString(); e.printStackTrace(); } catch (IOException e) { strResult = e.getMessage().toString(); e.printStackTrace(); } catch (Exception e) { strResult = e.getMessage().toString(); e.printStackTrace(); } return returnValue; }2,解析Json：
/** * 解析JSON数据为人人对象 * * @param renrenJsonData * @return */ public static List<Renren> parseRenrenFromJson(String renrenJsonData) { List<Renren> renrenList = new ArrayList<Renren>(); try { JSONArray jsonArray = new JSONArray(renrenJsonData); int length = jsonArray.length(); for (int i = 0; i < length; ++i) { JSONObject jsonObject = jsonArray.getJSONObject(i); Renren renren = new Renren(); renren.setId(jsonObject.getString("id")); renren.setName(jsonObject.getString("name")); renren.setHeadurl(jsonObject.getString("headurl")); renrenList.add(renren); } return renrenList; } catch (JSONException e) { } return null; }写一个RenRen bean用来保存信息；
public class Renren { protected String id; protected String name; protected String headurl; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getHeadurl() { return headurl; } public void setHeadurl(String headurl) { this.headurl = headurl; }}3,使用AsyncTask来异步网络连接和查询：
FriendsTask task = new FriendsTask(); task.execute("10");FriendsTask的代码如下：
class FriendsTask extends AsyncTask<String, Integer, String> { @Override protected String doInBackground(String... params) { Log.i("FriendsTask", "----doInBackground----"); getParams(); return sendRequest(); } @Override protected void onCancelled() { Log.i("FriendsTask", "----onCancelled----"); super.onCancelled(); } @Override protected void onPostExecute(String result) { Log.i("FriendsTask", "----onPostExecute----"); Log.i("FriendsTask", "result:" + result); // message.setText(result); pDialog.dismiss(); if (result.equals("1")) { mHandler.sendEmptyMessage(SUCCESS); } else { mHandler.sendEmptyMessage(FAILURE); } } @Override protected void onPreExecute() { Log.i("FriendsTask", "----onPreExecute----"); // 任务启动，可以在这里显示一个对话框，这里简单处理 pDialog = ProgressDialog.show(RenrenFriendsActivity.this, "Importing", "importing..."); } @Override protected void onProgressUpdate(Integer... values) { // 更新进度 // message.setText(values[0]); Log.i("FriendsTask", "---onProgressUpdate----"); } }4，使用一个adapter来适配listview，由于返回头像的时候只返回的是url，所以，通过新开一个线程来异步加载头像图片。
Adapter类如下：
class FriendsAdapater extends BaseAdapter { private AsyncImageLoader asyncImageLoader = new AsyncImageLoader(); // 异步获取图片 TextView userName; ImageView userImage; public int getCount() { return renrenList == null ? 0 : renrenList.size(); } public Object getItem(int position) { return renrenList == null ? null : renrenList.get(position); } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { convertView = LayoutInflater.from(getApplicationContext()).inflate( R.layout.renren_friend_item, null); userName = (TextView) convertView.findViewById(R.id.username); userImage = (ImageView) convertView.findViewById(R.id.userimage); Renren renren = renrenList.get(position); if (renren != null) { convertView.setTag(renren.getId()); userImage.setTag(renren.getHeadurl()); userName.setText(renren.getName()); // 异步加载图片并显示 Drawable cachedImage = asyncImageLoader.loadDrawable(renren, new ImageCallback() { public void imageLoaded(Drawable imageDrawable, String imageUrl) { ImageView imageView = (ImageView) friendsListView .findViewWithTag(imageUrl); if (imageView != null) { imageView.setImageDrawable(imageDrawable); } } }); if (cachedImage != null) { userImage.setImageDrawable(cachedImage); } else {// 如果没有图片，就以一个载入的图片代替显示 userImage.setImageResource(R.drawable.avatar_default); } } return convertView; } }异步加载图片的类AsyncImageLoader如下：
public class AsyncImageLoader { private HashMap<String, SoftReference<Drawable>> imageCache; // 缓存图片 public AsyncImageLoader() { imageCache = new HashMap<String, SoftReference<Drawable>>(); } public Drawable loadDrawable(final Renren renren, final ImageCallback imageCallback) { final String imageId = renren.getId(); final String imageURL = renren.getHeadurl(); // 判断缓存中是否已经存在图片，如果存在则直接返回 if (imageCache.containsKey(imageId)) { SoftReference<Drawable> softReference = imageCache.get(imageId); Drawable drawable = softReference.get(); if (drawable != null) { return drawable; } } final Handler handler = new Handler() { public void handleMessage(Message message) { imageCallback.imageLoaded((Drawable) message.obj, imageURL); } }; // 开辟一个新线程去下载图片，并用Handler去更新UI new Thread() { @Override public void run() { Drawable drawable = loadImageFromUrl(imageURL); imageCache.put(imageURL, new SoftReference<Drawable>(drawable)); Message message = handler.obtainMessage(0, drawable); handler.sendMessage(message); } }.start(); return null; } // 从URL下载图片 public static Drawable loadImageFromUrl(String url) { URL m; InputStream i = null; try { m = new URL(url); i = (InputStream) m.getContent(); } catch (MalformedURLException e1) { e1.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } Drawable d = Drawable.createFromStream(i, "src"); return d; } // 回调接口 public interface ImageCallback { // 回调函数 public void imageLoaded(Drawable imageDrawable, String imageUrl); }}好了，这样你就可以从人人网获取好友信息了。
更多接口请查看：
http://wiki.dev.renren.com/wiki/API#.E5.9F.BA.E7.A1.80API