Android AsyncHttpClient-白红宇

Android AsyncHttpClient

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发布时间：2019-06-14

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Overview

An asynchronous callback-based Http client for Android built on top of Apache’s libraries. All requests are made outside of your app’s main UI thread, but any callback logic will be executed on the same thread as the callback was created using Android’s Handler message passing.

Features

Make asynchronous HTTP requests, handle responses in anonymous callbacks

HTTP requests happen outside the UI thread

Requests use a threadpool to cap concurrent resource usage

GET/POST params builder (RequestParams)

Multipart file uploads with no additional third party libraries

Tiny size overhead to your application, only 25kb for everything

Automatic smart request retries optimized for spotty mobile connections

Automatic gzip response decoding support for super-fast requests

Binary file (images etc) downloading with BinaryHttpResponseHandler

Built-in response parsing into JSON with JsonHttpResponseHandler

Persistent cookie store, saves cookies into your app’s SharedPreferences

Who is Using It?

Instagram is the #1 photo app on android, with over 10million users

Social game discovery app with millions of users

Popular personal online music radio service

Pose is the #1 fashion app for sharing and discovering new styles

Pocket Salsa is the easiest way to learn how to dance salsa.

Send me a on github to let me know if you are using this library in a released android application!

Installation & Basic Usage

Download the latest .jar file from github and place it in your Android app’s libs/ folder.

Import the http package.

import com.loopj.android.http.*;

Create a new AsyncHttpClient instance and make a request:

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

Recommended Usage: Make a Static Http Client

In this example, we’ll make a http client class with static accessors to make it easy to communicate with Twitter’s API.

import com.loopj.android.http.*;public class TwitterRestClient {
         private static final String BASE_URL = "http://api.twitter.com/1/";  private static AsyncHttpClient client = new AsyncHttpClient();  public static void get(String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
             client.get(getAbsoluteUrl(url), params, responseHandler);  }  public static void post(String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
             client.post(getAbsoluteUrl(url), params, responseHandler);  }  private static String getAbsoluteUrl(String relativeUrl) {
             return BASE_URL + relativeUrl;  }}

This then makes it very easy to work with the Twitter API in your code:

import org.json.*;import com.loopj.android.http.*;class TwitterRestClientUsage {
           public void getPublicTimeline() throws JSONException {
               TwitterRestClient.get("statuses/public_timeline.json", null, new JsonHttpResponseHandler() {
                   @Override            public void onSuccess(JSONArray timeline) {
                       // Pull out the first event on the public timeline                JSONObject firstEvent = timeline.get(0);                String tweetText = firstEvent.getString("text");                // Do something with the response                System.out.println(tweetText);            }        });    }}

Check out the , and Javadocs for more details.

Persistent Cookie Storage with `PersistentCookieStore`

This library also includes a PersistentCookieStore which is an implementation of the Apache HttpClient CookieStore interface that automatically saves cookies to SharedPreferences storage on the Android device.

This is extremely useful if you want to use cookies to manage authentication sessions, since the user will remain logged in even after closing and re-opening your app.

First, create an instance of AsyncHttpClient:

AsyncHttpClient myClient = new AsyncHttpClient();

Now set this client’s cookie store to be a new instance of PersistentCookieStore, constructed with an activity or application context (usually this will suffice):

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

Any cookies received from servers will now be stored in the persistent cookie store.

To add your own cookies to the store, simply construct a new cookie and call addCookie:

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

See the for more information.

Adding GET/POST Parameters with `RequestParams`

The RequestParams class is used to add optional GET or POST parameters to your requests.RequestParams can be built and constructed in various ways:

Create empty RequestParams and immediately add some parameters:

RequestParams params = new RequestParams();params.put("key", "value");params.put("more", "data");

Create RequestParams for a single parameter:

RequestParams params = new RequestParams("single", "value");

Create RequestParams from an existing Map of key/value strings:

HashMap
       
         paramMap = new HashMap
        
         ();paramMap.put("key", "value");RequestParams params = new RequestParams(paramMap);

See the for more information.

Uploading Files with `RequestParams`

The RequestParams class additionally supports multipart file uploads as follows:

Add an InputStream to the RequestParams to upload:

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

Add a File object to the RequestParams to upload:

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

Add a byte array to the RequestParams to upload:

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

See the for more information.

Downloading Binary Data with `BinaryHttpResponseHandler`

The BinaryHttpResponseHandler class can be used to fetch binary data such as images and other files. For example:

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    }});

See the for more information.

Adding HTTP Basic Auth credentials

Some requests may need username/password credentials when dealing with API services that use HTTP Basic Access Authentication requests. You can use the method setBasicAuth()to provide your credentials.

Set username/password for any host and realm for a particular request. By default the Authentication Scope is for any host, port and realm.

AsyncHttpClient client = new AsyncHttpClient();client.setBasicAuth("username","password/token");client.get("http://example.com");

You can also provide a more specific Authentication Scope (recommended)

AsyncHttpClient client = new AsyncHttpClient();client.setBasicAuth("username","password", new AuthScope("example.com", 80, AuthScope.ANY_REALM));client.get("http://example.com");

See the for more information.

Building from Source

To build a .jar file from source, first make a clone of the android-async-http github repository. You’ll then need to copy the local.properties.dist file to local.properties and edit the sdk.dir setting to point to where you have the android sdk installed. You can then run: