重点，多了一个final
MainActivity.java
package com.example.applicationt; import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.Toast; import org.jetbrains.annotations.NotNull; import java.io.IOException; import okhttp3.Call; import okhttp3.Callback; import okhttp3.FormBody; import okhttp3.OkHttpClient; import okhttp3.Request; import okhttp3.Response; public class MainActivity extends AppCompatActivity { private Button btns; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btns=findViewById(R.id.btn); //1 . 拿到OkHttpClient对象 OkHttpClient client=new OkHttpClient(); //2 . 构建FormBody,传入参数 FormBody formBody=new FormBody.Builder() .add("name","13") .add("eee","44") .add("name","23") .add("eee","24") .build(); //3、构建Request,将FormBody作为Post方法的参数传入，get请求与post请求相比较就是多了这一步 final Request request=new Request.Builder() //注意这里是final .url("https:///www.baidu.com") .post(formBody) .build(); //4 . 将Request封装为Call Call call=client.newCall(request); //5 . 调用请求,重写回调方法 call.enqueue(new Callback() { @Override public void onFailure(@NotNull Call call, @NotNull IOException e) { Toast.makeText(MainActivity.this,"post提交",Toast.LENGTH_SHORT).show(); } @Override public void onResponse(@NotNull Call call, @NotNull Response response) throws IOException { final String res=response.body().string(); //注意这里也是final runOnUiThread(new Runnable() { @Override public void run() { btns.setText(res); } }); } }); } }
activity_main.xml
<?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity"> <Button android:id="@+id/btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </androidx.constraintlayout.widget.ConstraintLayout>同样不要文件在清单文件里面添加联网权限
