安卓网络请求和图片加载

1 网络如果是http  

  在res 下创建xml文件  再创建   network-security-config.xml    

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <base-config  cleartextTrafficPermitted="true">
        <trust-anchors>
            <certificates src="system"/>
            <certificates src="user"/>
        </trust-anchors>
    </base-config>
</network-security-config>

在Androidmanifest 

//网络权限

<uses-permission android:name="android.permission.INTERNET"/>

<application

  android:networkSecurityConfig="@xml/network_security_config">

</application>

在build.gradle
 

AS引用
dependencies {
   
    implementation 'com.squareup.okhttp3:okhttp:3.12.0'
    implementation 'com.squareup.picasso:picasso:2.71828'
  
}
//数据加载
//Activy

//import okhttp3.Callback;
//import okhttp3.OkHttpClient;
//import okhttp3.Request;
//import okhttp3.Call;
//import okhttp3.Response;

public  void addNework(){

    String url = "";
    OkHttpClient okHttpClient = new OkHttpClient();
    final Request request = new Request.Builder()
            .url(url)
            .get()//默认就是GET请求，可以不写
            .build();
    Call call = okHttpClient.newCall(request);

    call.enqueue(new Callback() {
        @Override
        public void onFailure(Call call, IOException e) {

           Log.v("Tag","eff"+e);

        }

        @Override
        public void onResponse(Call call, Response response) throws IOException {

            Log.v("TAG", "onResponse: " + response.body().string());

        }
    });




}

//图片下载

public void aaImageView(){

    Picasso.get().load("http://www.chaiqian88.com/d/file/sybanner/2018-10-23/1e184615665d4cd9a6bb82949d1614b0.png").into(imageView);
//       Picasso.with(this).load().info();

//.onlyScaleDown()当调用了resize 方法重新设置图片尺寸的时候，调用onlyScaleDown 方法，只有当原始图片的尺寸大于我们指定的尺寸时，resize才起作用,
       //Picasso.get().load("http://www.chaiqian88.com/d/file/sybanner/2018-10-23/1e184615665d4cd9a6bb82949d1614b0.png").resize(400,200).onlyScaleDown().into(imageView);
   }