AsyncHttpClient, RequestParams ,AsyncHttpResponseHandler三个类使用方法



(1)AsyncHttpClient
public class AsyncHttpClient extends java.lang.Object
 该类通常用在android应用程序中创建异步GET, POST, PUT和DELETE HTTP请求，请求参数通过RequestParams实例创建，响应通过重写匿名内部类 ResponseHandlerInterface的方法处理。
例子：

 AsyncHttpClient client = new AsyncHttpClient();
  client.get("http://www.google.com", new ResponseHandlerInterface() {
      @Override
      public void onSuccess(String response) {
          System.out.println(response);
      }
  });

(2)RequestParams
public class RequestParams extends java.lang.Object 
用于创建AsyncHttpClient实例中的请求参数(包括字符串或者文件)的集合
例子：

 RequestParams params = new RequestParams();
  params.put("username", "james");
  params.put("password", "123456");
  params.put("email", "[email protected]");
  params.put("profile_picture", new File("pic.jpg")); // Upload a File
  params.put("profile_picture2", someInputStream); // Upload an InputStream
  params.put("profile_picture3", new ByteArrayInputStream(someBytes)); // Upload some bytes

  Map<String, String> map = new HashMap<String, String>();
  map.put("first_name", "James");
  map.put("last_name", "Smith");
  params.put("user", map); // url params: "user[first_name]=James&user[last_name]=Smith"

  Set<String> set = new HashSet<String>(); // unordered collection
  set.add("music");
  set.add("art");
  params.put("like", set); // url params: "like=music&like=art"

  List<String> list = new ArrayList<String>(); // Ordered collection
  list.add("Java");
  list.add("C");
  params.put("languages", list); // url params: "languages[]=Java&languages[]=C"

  String[] colors = { "blue", "yellow" }; // Ordered collection
  params.put("colors", colors); // url params: "colors[]=blue&colors[]=yellow"

  List<Map<String, String>> listOfMaps = new ArrayList<Map<String, String>>();
  Map<String, String> user1 = new HashMap<String, String>();
  user1.put("age", "30");
  user1.put("gender", "male");
  Map<String, String> user2 = new HashMap<String, String>();
  user2.put("age", "25");
  user2.put("gender", "female");
  listOfMaps.add(user1);
  listOfMaps.add(user2);
  params.put("users", listOfMaps); // url params: "users[][age]=30&users[][gender]=male&users[][age]=25&users[][gender]=female"

  AsyncHttpClient client = new AsyncHttpClient();
  client.post("http://myendpoint.com", params, responseHandler);

(3)public class AsyncHttpResponseHandler extends java.lang.Object implements ResponseHandlerInterface
用于拦截和处理由AsyncHttpClient创建的请求。在匿名类AsyncHttpResponseHandler中的重写 onSuccess(int, org.apache.http.Header[], byte[])方法用于处理响应成功的请求。此外，你也可以重写 onFailure(int, org.apache.http.Header[], byte[], Throwable), onStart(), onFinish(), onRetry() 和onProgress(int, int)方法
例子：

 AsyncHttpClient client = new AsyncHttpClient();
  client.get("http://www.google.com", new AsyncHttpResponseHandler() {
      @Override
      public void onStart() {
          // Initiated the request
      }

      @Override
      public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
          // Successfully got a response
      }

      @Override
      public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable error)
  {
          // Response failed :(
      }

      @Override
      public void onRetry() {
          // Request was retried
      }

      @Override
      public void onProgress(int bytesWritten, int totalSize) {
          // Progress notification
      }

      @Override
      public void onFinish() {
          // Completed the request (either success or failure)
      }
  });

6.利用PersistentCookieStore持久化存储cookie
PersistentCookieStore类用于实现Apache HttpClient的CookieStore接口，可以自动的将cookie保存到Android设备的SharedPreferences中，如果你打算使用cookie来管理验证会话，这个非常有用，因为用户可以保持登录状态，不管关闭还是重新打开你的app
(1)首先创建 AsyncHttpClient实例对象

 AsyncHttpClient myClient = new AsyncHttpClient();

(2)将客户端的cookie保存到PersistentCookieStore实例对象,带有activity或者应用程序context的构造方法

 PersistentCookieStore myCookieStore = new PersistentCookieStore(this);
 myClient.setCookieStore(myCookieStore);

(3)任何从服务器端获取的cookie都会持久化存储到myCookieStore中，添加一个cookie到存储中，只需要构造一个新的cookie对象，并且调用addCookie方法

 BasicClientCookie newCookie = new BasicClientCookie("cookiesare", "awesome");
 newCookie.setVersion(1);
 newCookie.setDomain("mydomain.com");
 newCookie.setPath("/");
 myCookieStore.addCookie(newCookie);

7.利用RequestParams上传文件
类RequestParams支持multipart file 文件上传
(1)在RequestParams 对象中添加InputStream用于上传

 InputStream myInputStream = blah;
 RequestParams params = new RequestParams();
 params.put("secret_passwords", myInputStream, "passwords.txt");

(2)添加文件对象用于上传

 File myFile = new File("/path/to/file.png");
 RequestParams params = new RequestParams();
 try {
     params.put("profile_picture", myFile);
 } catch(FileNotFoundException e) {}

(3)添加字节数组用于上传

 byte[] myByteArray = blah;
 RequestParams params = new RequestParams();
 params.put("soundtrack", new ByteArrayInputStream(myByteArray), "she-wolf.mp3");

8.用BinaryHttpResponseHandler下载二进制数据

 BinaryHttpResponseHandler用于获取二进制数据如图片和其他文件
 AsyncHttpClient client = new AsyncHttpClient();
 String[] allowedContentTypes = new String[] { "image/png", "image/jpeg" };
 client.get("http://example.com/file.png", new BinaryHttpResponseHandler(allowedContentTypes) {
     @Override
     public void onSuccess(byte[] fileData) {
         // Do something with the file
     }
 });