首先添加一个依赖：
mplementation 'com.squareup.okhttp3:okhttp:3.11.0'
然后添加权限 网络、读写、
<uses-permission android:name="android.permission.INTERNET"/> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
布局：就两个按钮，一个图片
<LinearLayout
android:orientation="vertical"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="@+id/btn_upload"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content"
android:text="上传图片" />
<Button
android:id="@+id/btn_load"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content"
android:text="下载图片" />
</LinearLayout>
<ImageView
android:id="@+id/img_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
逻辑---Activity
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import java.io.File;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.MediaType;
import okhttp3.MultipartBody;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
public static final String PATH = "https://10.url.cn/eth/ajNVdqHZLLAxibwnrOxXSzIxA76ichutwMCcOpA45xjiapneMZsib7eY4wUxF6XDmL2FmZEVYsf86iaw/";
public static final String URL = "https://www.718shop.com/sell/sell.m.picture.upload.do";
private Button btn_upload;
private Button btn_load;
private ImageView img_view;
public static final int FALL = 123;
public static final int SUCCESS = 100;
private Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what){
case SUCCESS: //加载网络成功,进行UI的更新,处理得到的图片资源
byte[] obj = (byte[]) msg.obj;//通过message,拿到字节数组
Bitmap bitmap = BitmapFactory.decodeByteArray(obj, 0, obj.length);//使用BitmapFactory工厂,把字节数组转换为bitmap
img_view.setImageBitmap(bitmap); //通过ImageView,设置图片
break;
case FALL://当加载网络失败,执行的逻辑代码
Toast.makeText(MainActivity.this,"下载失败",Toast.LENGTH_SHORT).show();
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化控件
initView();
}
/**
* 根据点击事件获取络上的图片资源,使用的是OKhttp框架
*
* @param v
*/
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_upload://上传
//注意打印以下路径
Log.i("yz",""+Environment.getExternalStorageDirectory() + "/Pictures/Screenshots");
//创建上传文件对象
File file = new File(Environment.getExternalStorageDirectory() + "/Pictures/Screenshots", "meinv.png");
//创建RequestBody封装参数
RequestBody requestBody = 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", "meinv.png", requestBody)
.build();
//创建Request
Request requests = new Request.Builder()
.url(URL)
.post(multipartBody)
.build();
//创建okhttp对象
OkHttpClient okHttpClients = new OkHttpClient.Builder()
.readTimeout(10, TimeUnit.SECONDS)
.connectTimeout(10,TimeUnit.SECONDS)
.writeTimeout(10,TimeUnit.SECONDS)
.build();
//上传完图片,得到服务器反馈数据
okHttpClients.newCall(requests).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
Log.i("yz",""+e);
}
@Override
public void onResponse(Call call, Response response) throws IOException {
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MainActivity.this,"上传成功",Toast.LENGTH_SHORT).show();
}
});
}
});
break;
case R.id.btn_load://下载
//1. 创建OKhttpClient对象
OkHttpClient okHttpClient = new OkHttpClient.Builder()
.readTimeout(10, TimeUnit.SECONDS)
.connectTimeout(10,TimeUnit.SECONDS)
.writeTimeout(10,TimeUnit.SECONDS)
.build();
//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).build();
//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[] bytes = response.body().bytes();
//通过handler更新UI
Message msg = handler.obtainMessage();
msg.obj = bytes;
msg.what = SUCCESS;
handler.sendMessage(msg);
}
});
break;
}
}
private void initView() {
btn_upload = findViewById(R.id.btn_upload);
btn_load =findViewById(R.id.btn_load);
img_view = findViewById(R.id.img_view);
btn_upload.setOnClickListener(this);
btn_load.setOnClickListener(this);
}
}