前言
上一篇介绍了OkHttp2.x的用法,这一篇文章我们来对照OkHttp2.x版本来看看,OkHttp3使用起来有那些变化。当然,看这篇文章前建议看一下前一篇文章。
1.使用前准备
Android Studio 配置gradle:
compile 'com.squareup.okhttp3:okhttp:3.2.0' compile 'com.squareup.okio:okio:1.7.0'
添加网络权限:
2.异步GET请求
惯例,请求百度:
private void getAsynHttp() { mOkHttpClient=new OkHttpClient(); Request.Builder requestBuilder = new Request.Builder().url("http://www.baidu.com"); //可以省略,默认是GET请求 requestBuilder.method("GET",null); Request request = requestBuilder.build(); Call mcall= mOkHttpClient.newCall(request); mcall.enqueue(new Callback() { @Override public void onFailure(Call call, IOException e) { } @Override public void onResponse(Call call, Response response) throws IOException { if (null != response.cacheResponse()) { String str = response.cacheResponse().toString(); Log.i("wangshu", "cache---" + str); } else { response.body().string(); String str = response.networkResponse().toString(); Log.i("wangshu", "network---" + str); } runOnUiThread(new Runnable() { @Override public void run() { Toast.makeText(getApplicationContext(), "请求成功", Toast.LENGTH_SHORT).show(); } }); } }); }
与2.x版本并没有什么不同,比较郁闷的是回调仍然不在UI线程。
2.异步POST请求
OkHttp3异步POST请求和OkHttp2.x有一些差别就是没有FormEncodingBuilder这个类,替代它的是功能更加强大的FormBody:
private void postAsynHttp() { mOkHttpClient=new OkHttpClient(); RequestBody formBody = new FormBody.Builder() .add("size", "10") .build(); Request request = new Request.Builder() .url("http://api.1-blog.com/biz/bizserver/article/list.do") .post(formBody) .build(); Call call = mOkHttpClient.newCall(request); call.enqueue(new Callback() { @Override public void onFailure(Call call, IOException e) { } @Override public void onResponse(Call call, Response response) throws IOException { String str = response.body().string(); Log.i("wangshu", str); runOnUiThread(new Runnable() { @Override public void run() { Toast.makeText(getApplicationContext(), "请求成功", Toast.LENGTH_SHORT).show(); } }); } }); }
3.异步上传文件
上传文件本身也是一个POST请求,上一篇没有讲,这里我们补上。首先定义上传文件类型:
public static final MediaType MEDIA_TYPE_MARKDOWN = MediaType.parse("text/x-markdown; charset=utf-8");
将sdcard根目录的wangshu.txt文件上传到服务器上:
private void postAsynFile() { mOkHttpClient=new OkHttpClient(); File file = new File("/sdcard/wangshu.txt"); Request request = new Request.Builder() .url("https://api.github.com/markdown/raw") .post(RequestBody.create(MEDIA_TYPE_MARKDOWN, file)) .build(); mOkHttpClient.newCall(request).enqueue(new Callback() { @Override public void onFailure(Call call, IOException e) { } @Override public void onResponse(Call call, Response response) throws IOException { Log.i("wangshu",response.body().string()); } }); }
当然如果想要改为同步的上传文件只要调用 mOkHttpClient.newCall(request).execute()就可以了。
在wangshu.txt文件中有一行字“Android网络编程(六)OkHttp3用法全解析”我们运行程序点击发送文件按钮,最终请求网络返回的结果就是我们txt文件中的内容 :
当然不要忘了添加如下权限:
4.异步下载文件
下载文件同样在上一篇没有讲到,实现起来比较简单,在这里下载一张图片,我们得到Response后将流写进我们指定的图片文件中就可以了。
private void downAsynFile() { mOkHttpClient = new OkHttpClient(); String url = "https://img-my.csdn.net/uploads/201603/26/1458988468_5804.jpg"; Request request = new Request.Builder().url(url).build(); mOkHttpClient.newCall(request).enqueue(new Callback() { @Override public void onFailure(Call call, IOException e) { } @Override public void onResponse(Call call, Response response) { InputStream inputStream = response.body().byteStream(); FileOutputStream fileOutputStream = null; try { fileOutputStream = new FileOutputStream(new File("/sdcard/wangshu.jpg")); byte[] buffer = new byte[2048]; int len = 0; while ((len = inputStream.read(buffer)) != -1) { fileOutputStream.write(buffer, 0, len); } fileOutputStream.flush(); } catch (IOException e) { Log.i("wangshu", "IOException"); e.printStackTrace(); } Log.d("wangshu", "文件下载成功"); } }); }
5.异步上传Multipart文件
这种场景很常用,我们有时会上传文件同时还需要传其他类型的字段,OkHttp3实现起来很简单,需要注意的是没有服务器接收我这个Multipart文件,所以这里只是举个例子,具体的应用还要结合实际工作中对应的服务器。
首先定义上传文件类型:private static final MediaType MEDIA_TYPE_PNG = MediaType.parse("image/png");
private void sendMultipart(){ mOkHttpClient = new OkHttpClient(); RequestBody requestBody = new MultipartBody.Builder() .setType(MultipartBody.FORM) .addFormDataPart("title", "wangshu") .addFormDataPart("image", "wangshu.jpg", RequestBody.create(MEDIA_TYPE_PNG, new File("/sdcard/wangshu.jpg"))) .build(); Request request = new Request.Builder() .header("Authorization", "Client-ID " + "...") .url("https://api.imgur.com/3/image") .post(requestBody) .build(); mOkHttpClient.newCall(request).enqueue(new Callback() { @Override public void onFailure(Call call, IOException e) { } @Override public void onResponse(Call call, Response response) throws IOException { Log.i("wangshu", response.body().string()); } });}
6.设置超时时间和缓存
和OkHttp2.x有区别的是不能通过OkHttpClient直接设置超时时间和缓存了,而是通过OkHttpClient.Builder来设置,通过builder配置好OkHttpClient后用builder.build()来返回OkHttpClient,所以我们通常不会调用new OkHttpClient()来得到OkHttpClient,而是通过builder.build():
File sdcache = getExternalCacheDir(); int cacheSize = 10 * 1024 * 1024; OkHttpClient.Builder builder = new OkHttpClient.Builder() .connectTimeout(15, TimeUnit.SECONDS) .writeTimeout(20, TimeUnit.SECONDS) .readTimeout(20, TimeUnit.SECONDS) .cache(new Cache(sdcache.getAbsoluteFile(), cacheSize)); OkHttpClient mOkHttpClient=builder.build();
7.关于取消请求和封装
取消请求仍旧可以调用call.cancel(),这个没有变化,不明白的可以查看上一篇文章,这里就不赘述了,封装上一篇也讲过仍旧推荐,它目前是基于OkHttp3来进行封装的。
8.关于源码Demo
源码Demo很简单就四个按钮用来测试上面讲到的内容: