android AsyncHttpClient 开源框架的使用

浏览数：32 / 时间：2015年06月11日

AsyncHttpClient

1.在很多时候android都需要进行网络的操作，而android自带的HttpClient可以实现，但要进行很多网络连接的时候(如：下载很多图片)，就需要线程池来进行管理，但默认都是阻塞式操作。这种模型效率不高，对并发要求高的 APP 来讲，并不适用，要用AsyncHttpClient 就必须下载一个jar包 ------>> 下载地址。

2.AsyncHttpClient框架是异步的框架，而且已经封装好了了线程池的操作。所以对网络的操作都是很快的！

3.在AsyncHttpClient框架中主要的类如下：

主要用到的类有AsyncHttpClient , JsonHttpResponseHandler , RequestParams,

3.请求的方法：

AsyncHttpClient.post(arg0,arg1,arg2);

arg0:是你post请求的url

arg1:是要发送给服务器的数据，他是<key,value>形式的

arg2:发送请求的一连串操作如下：

JsonHttpResponseHandler是AsyncHttpResponseHandler的子类

 1 JsonHttpResponseHandler handler = new JsonHttpResponseHandler() {
 2             @Override
 3             public void onFailure(Throwable arg0, String arg1) {
 4 
 5                 super.onFailure(arg0, arg1);
 6 
 7             }
 8 
 9             @Override
10             public void onFinish() {
11 
12                 super.onFinish();
13 
14             }
15 
16             @Override
17             public void onSuccess(JSONObject arg1) {
18                 super.onSuccess(arg1);
19 
20             }
21 
22             @Override
23             public void onStart() {
24 
25                 super.onStart();
26 
27             }
28         };

　　　　1)onStart() 方法是开始发送请求的时候执行的，一般是把progressDialog放在这里面显示，提示用户等待

　　　　2)onFailure() 如果请求失败了，就会执行该方法，其余方法就都不执行了，用于提示用户网络出现故障

　　　　3)onSuccess() 是请求成功后，服务器就会返回JSONObject， arg1就是返回的JSONObject，在里面解析JSONObject来回去数据，并显示在UI上

　　　　4)onFinish() 当发送请求成功后，就执行onFinish()

如上就是一些基本的用法。

这里贴一个结合AsyncHttpClient + 单例模式 + 观察者模式的例子

接口：

public interface TaskListener {
    
    public abstract void start();
    public abstract String contentype(); // text, file
    public abstract String filepath();
    public abstract String requestUrl();
    public abstract JSONObject requestData();
    public abstract void messageUpdated(JSONObject msg);
    public abstract void failure(String str); 
    public abstract void finish();
    public abstract boolean needCacheTask();
    
    public abstract String readCache();
    public abstract void updateCacheDate(List<HashMap<String, Object>> cacheData);
        
}

实现：

 19 
 20 public class CommandBase {
 21 
 22     private static CommandBase m_instance = null;
 23 
 24     private HashMap<AsyncHttpResponseHandler, TaskListener> m_task = new HashMap<AsyncHttpResponseHandler, TaskListener>();
 25 
 26     private AsyncHttpClient m_httpClient = new AsyncHttpClient();
 27 
 28     private UploadQueue m_uploadQueue = null;
 29     private HashMap<AsyncHttpResponseHandler, UploadItem> m_tempRequest = new HashMap<AsyncHttpResponseHandler, UploadItem>();
 30 
 31     private static String m_account = "";
 32     private static String m_session = "";
 33 
 34     private static String HostUrl = "http://222.18.162.187:8080/wasp/webservice/ap/";
 35     private static JSONObject m_postData = new JSONObject();
 36 
 37     Context m_context;
 38     Context m_currContext;
 39     Activity m_currActivity;
 40 
 41     public void setCurrActivityContext(Context context, Activity activity) {
 42         m_currContext = context;
 43         m_currActivity = activity;
 44     }
 45 
 46     public void setMainActivityContext(Context context) {
 47         m_context = context;
 48 
 49         if (m_uploadQueue == null)
 50             m_uploadQueue = new UploadQueue(m_context);
 51     }
 52 
 53     public static CommandBase instance() {
 54         if (m_instance == null)
 55             m_instance = new CommandBase();
 56 
 57         return m_instance;
 58     }
 59 
 60     private CommandBase() {
 61         m_httpClient.addHeader("Content-Type", "application/json");
 62         m_httpClient.addHeader("Request-Client", "mobile/1.0.0");
 63 
 64         /*
 65          * JSONObject userData = new JSONObject(); try { userData.put("account",
 66          * m_account); userData.put("session", m_session);
 67          * m_postData.put("user", userData); } catch (JSONException e) {
 68          * e.printStackTrace(); }
 69          */
 70     }
 71 
 72     public void setUserInfo(String name, String session) {
 73         m_account = name;
 74         m_session = session;
 75         System.out.println("setUser");
 76         System.out.println("account=" + m_account);
 77         JSONObject userData = new JSONObject();
 78         try {
 79             userData.put("account", m_account);
 80             userData.put("session", m_session);
 81             m_postData.put("user", userData);
 82         } catch (JSONException e) {
 83             e.printStackTrace();
 84         }
 85     }
 86 
 87     CacheManager manager = new CacheManager();
 88 
 89     public void readCache(final TaskListener taskListener) {
 90         List<HashMap<String, Object>> list = new ArrayList<HashMap<String, Object>>();
 91         String queryStr = taskListener.readCache();
 92         list = manager.getCacheData(queryStr);
 93         taskListener.updateCacheDate(list);
 94         request(taskListener);
 95     }
 96 
 97     public void request(final TaskListener task) {
 98         RequestParams postParam = new RequestParams();
 99         postParam.put("req", requestData(task.requestData()));
100 
101         JsonHttpResponseHandler handler = new JsonHttpResponseHandler() {
102             @Override
103             public void onFailure(Throwable arg0, String arg1) {
104                 task.failure(arg1);
105                 super.onFailure(arg0, arg1);
106                 System.out.println("网络连接失败..");
107                 if (task.needCacheTask() && m_uploadQueue != null
108                         && m_tempRequest.containsKey(this))
109                     m_uploadQueue.addItemToQueue(m_tempRequest.get(this));
110                 m_tempRequest.remove(this);
111                 Toast.makeText(m_currContext, "网络连接失败", Toast.LENGTH_SHORT)
112                         .show();
113             }
114 
115             @Override
116             public void onFinish() {
117                 task.finish();
118                 super.onFinish();
119                 System.out.println("请求结束");
120             }
121 
122             @Override
123             public void onSuccess(JSONObject arg1) {
124                 super.onSuccess(arg1);
125                 System.out.println("连接服务器成功！");
126                 System.out.println("结果=" + arg1);
127                 readData(arg1, this);
128             }
129 
130             @Override
131             public void onStart() {
132                 task.start();
133                 super.onStart();
134                 System.out.println("请求开始");
135             }
136         };
137 
138         // TODO: save network request to local DB
139         if (task.needCacheTask()) {
140             System.out.println("++++++++++++++++++++++++++++++++++++++++");
141             m_tempRequest.put(
142                     handler,
143                     new UploadItem(0, requestUrl(task.requestUrl()),
144                             requestData(task.requestData()),
145                             task.contentype() == "text" ? 0 : 1, task
146                                     .filepath()));
147 
148         }
149 
150         m_task.put(handler, task);
151         m_httpClient.post(requestUrl(task.requestUrl()), postParam, handler);
152 
153         
154 
155     }
156 
157     private String requestUrl(String ap) {
158         return HostUrl + ap + ".action";
159     }
160 
161     private String requestData(JSONObject data) {
162         JSONObject postData = new JSONObject();
163         postData = m_postData;
164         try {
165             postData.put("data", data);
166         } catch (JSONException e) {
167             e.printStackTrace();
168         }
169         System.out.println("postData=" + postData);
170         return postData.toString();
171     }
172 
173     private void readData(JSONObject data, AsyncHttpResponseHandler handler) {
174         TaskListener task = m_task.get(handler);
175 
176         if (task == null) {
177             m_task.remove(handler);
178             m_tempRequest.remove(handler);
179             return;
180         }
181         // TODO: Check the response data has Error or not
182         try {
183             JSONObject object = data.getJSONObject("error");
184             String code = object.getString("code");
185             String errorTag = object.getString("string");
186             System.out.println("code=" + code);
187             System.out.println("error=" + errorTag);
188             if (code.equals("0")) {
189                 object = data.getJSONObject("data");
190                 task.messageUpdated(data);
191                 manager.updateCacheData(data);
192                 m_tempRequest.remove(handler);
193             } else if (code.equals("-99")) {
194                 Toast.makeText(m_currContext, "用户信息已过期,请重新登陆",
195                         Toast.LENGTH_SHORT).show();
196                 m_currActivity.finish();
197             } else {
198                 System.out.println("#####################");
199                 if (task.needCacheTask() && m_uploadQueue != null
200                         && m_tempRequest.containsKey(handler)) {
201                     System.out.println("_____________________________");
202                     m_uploadQueue.addItemToQueue(m_tempRequest.get(handler));
203                 }
204                 m_tempRequest.remove(handler);
205                 Toast.makeText(m_currContext, errorTag, Toast.LENGTH_SHORT)
206                         .show();
207             }
208         } catch (JSONException e) {
209             e.printStackTrace();
210             if (task.needCacheTask() && m_uploadQueue != null
211                     && m_tempRequest.containsKey(handler)) {
212                 m_uploadQueue.addItemToQueue(m_tempRequest.get(handler));
213             }
214             m_tempRequest.remove(handler);
215 
216         }
217 
218 
219         m_task.remove(handler);
220     }
221 
222 }