Android基于OkHttp实现下载和上传图片

本文实例为大家分享了okhttp实现下载图片和上传图片的具体代码，供大家参考，具体内容如下

mainactivity.java

public class mainactivity extends appcompatactivity {

  private string path = "https://10.url.cn/eth/ajnvdqhzllaxibwnroxxszixa76ichutwmccopa45xjiapnemzsib7ey4wuxf6xdml2fmzevysf86iaw/";
  private static final int success = 993;
  private static final int fall = 814;
  handler handler = new handler() {
    @override
    public void handlemessage(message msg) {
      switch (msg.what) {
        //加载网络成功,进行ui的更新,处理得到的图片资源
        case success:
          //通过message,拿到字节数组
          byte[] picture = (byte[]) msg.obj;
          //使用bitmapfactory工厂,把字节数组转换为bitmap
          bitmap bitmap = bitmapfactory.decodebytearray(picture, 0, picture.length);
          //通过imageview,设置图片
          mimageview_okhttp.setimagebitmap(bitmap);
          break;
        //当加载网络失败,执行的逻辑代码
        case fall:
          toast.maketext(mainactivity.this, "网络异常", toast.length_short).show();
          break;

        default:
          break;
      }
    }
  };
  private imageview mimageview_okhttp;

  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_main);
    //初始化控件
    initview();
  }

  private void initview() {
    mimageview_okhttp = (imageview) findviewbyid(r.id.imageview_okhttp);
  }

  /**
   * 根据点击事件获取络上的图片资源,使用的是okhttp框架
   *
   * @param view
   */
  public void picture_okhttp_bt(view view) {
    //1. 创建okhttpclient对象
    okhttpclient okhttpclient = new okhttpclient();
    //2.建立request对象,设置参数,请求方式如果是get,就不用设置,默认使用的就是get
    request request = new request.builder()
        .url(path)//设置请求网址
        .build();//建立request对象
    //3.创建一个call对象,参数是request对象,发送请求
    call call = okhttpclient.newcall(request);
    //4.异步请求,请求加入调度
    call.enqueue(new callback() {
      @override//请求失败回调
      public void onfailure(call call, ioexception e) {
        handler.sendemptymessage(fall);
      }

      @override//请求成功回调
      public void onresponse(call call, response response) throws ioexception {
        //得到从网上获取资源,转换成我们想要的类型
        byte[] picture_bt = response.body().bytes();
        //通过handler更新ui
        message message = handler.obtainmessage();
        message.obj = picture_bt;
        message.what = success;
        handler.sendmessage(message);

      }
    });
  }

  //当按钮点击时,执行使用okhttp上传图片到服务器(http://blog.csdn.net/tangxl2008008/article/details/51777355)
  //注意:有时候上传图片失败,是服务器规定还要上传一个key,如果开发中关于网络这一块出现问题,就多和面试官沟通沟通
  public void uploading(view view) {
    //图片上传接口地址
    string url = "https://www.718shop.com/sell/sell.m.picture.upload.do";
    //创建上传文件对象
    file file = new file(environment.getexternalstoragedirectory(), "big.jpg");

    //创建requestbody封装参数
    requestbody filebody = requestbody.create(mediatype.parse("application/octet-stream"), file);
    //创建multipartbody,给requestbody进行设置
    multipartbody multipartbody = new multipartbody.builder()
        .settype(multipartbody.form)
        .addformdatapart("image", "big.jpg", filebody)
        .build();
    //创建request
    request request = new request.builder()
        .url(url)
        .post(multipartbody)
        .build();

    //创建okhttp对象
    okhttpclient okhttpclient = new okhttpclient.builder()
        .connecttimeout(10, timeunit.seconds)
        .readtimeout(10, timeunit.seconds)
        .writetimeout(10, timeunit.seconds)
        .build();

    //上传完图片,得到服务器反馈数据
    okhttpclient.newcall(request).enqueue(new callback() {
      @override
      public void onfailure(call call, ioexception e) {
        log.e("ff", "uploadmultifile() e=" + e);
      }

      @override
      public void onresponse(call call, response response) throws ioexception {
        log.i("ff", "uploadmultifile() response=" + response.body().string());
      }
    });


  }

}

activity_main.xml

<relativelayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context="com.sn.picture_okhttp.mainactivity">


  <button
    android:id="@+id/button"
    android:onclick="picture_okhttp_bt"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="下载图片"
    android:layout_alignparenttop="true"
    android:layout_centerhorizontal="true"
    android:layout_margintop="59dp"/>

  <button
    android:text="上传图片"
    android:onclick="uploading"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/button2"
    android:layout_alignparenttop="true"
    android:layout_alignleft="@+id/button"
    android:layout_alignstart="@+id/button"/>

  <imageview
    android:id="@+id/imageview_okhttp"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignparentbottom="true"
    android:layout_centerhorizontal="true"/>

</relativelayout>

build.gradle //依赖

implementation 'com.squareup.okhttp3:okhttp:3.4.2'

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。