Java 将android real设备连接到应用程序以执行来自<；的GET请求；ipv4地址>；：8000使用改型

所以，我尝试在通过有线连接的真实android设备上通过改造获取以下API（使用Django rest框架生成）

"followers": [
        {
            "id": 4,
            "user_id": 11,
            "username": "aaaa",
            "profileImage": "",
            "profileTitle": null,
            "is_verified": false
        },
        {
            "id": 1,
            "user_id": 5,
            "username": "eeee",
            "profileImage": "",
            "profileTitle": "just try",
            "is_verified": true
        }
    ]

但当我打开应用程序时，它会崩溃，出现以下错误

Unfortunately, Dummy has stopped

下面是我的Java代码

主要活动

package com.example.dummy;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;

public class MainActivity extends AppCompatActivity {

    ImageButton home;
    ImageButton profile;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        home = (ImageButton)findViewById(R.id.imageButton);
        home.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                openMainActivity();
            }


        });

        profile = (ImageButton)findViewById(R.id.imageButton2);
        profile.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                openProfile();
            }
        });

    }

    private void openProfile() {
        Intent intent = new Intent(this,Profile.class);
        startActivity(intent);

    }

    private void openMainActivity() {
        Intent intent = new Intent(this,MainActivity.class);
        startActivity(intent);
    }
}

侧面图

package com.example.dummy;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.List;

import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

public class Profile extends AppCompatActivity {




    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_profile);

        final ListView listView = findViewById(R.id.listview);

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(Api.BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        Api api = retrofit.create(Api.class);

        Call<List<Followers>> call = api.getfollowers();

        call.enqueue(new Callback<List<Followers>>() {
            @Override
            public void onResponse(Call<List<Followers>> call, Response<List<Followers>> response) {
                List<Followers> followers = response.body();

                String[] names = new String[followers.size()];

                for (int i = 0; i < followers.size() ; i++){

                    names[i] = followers.get(i).getUsername();
                }

                listView.setAdapter(
                        new ArrayAdapter<String>(
                                getApplicationContext(),
                                android.R.layout.simple_dropdown_item_1line,
                                names

                        )
                );


            }

            @Override
            public void onFailure(Call<List<Followers>> call, Throwable t) {
                Toast.makeText(getApplicationContext(), t.getMessage() , Toast.LENGTH_SHORT).show();
            }
        });



    }
}

原料药

---

请帮助我查找上述代码中的错误或任何bug­­­­­­

您的异常说明了这一点。您忘记添加配置文件活动AndroidManifest.xml。您的异常说明了这一点。您忘记添加配置文件活动AndroidManifest.xml。

package com.example.dummy;

import android.widget.ImageView;

import org.w3c.dom.Text;

public class Followers {
     private int  id;
           private int user_id;
            private String username;
            private String imageurl;
            private Text profileTitle;
            private boolean is_verified;


    public String getImageurl() {
        return imageurl;
    }

    public int getId() {
        return id;
    }

    public int getUser_id() {
        return user_id;
    }

    public String getUsername() {
        return username;
    }



    public Text getProfileTitle() {
        return profileTitle;
    }

    public boolean isIs_verified() {
        return is_verified;
    }
}

package com.example.dummy;

import android.util.Log;

import java.util.List;

import retrofit2.Call;
import retrofit2.http.GET;

public interface Api {



        

        String BASE_URL = "http:// 192.168.43.49:8000/\n";

        @GET("followers/")
        Call<List<Followers>> getfollowers();


}


implementation 'com.squareup.retrofit2:converter-gson:2.4.0'
implementation 'com.squareup.retrofit2:retrofit:2.4.0'

2020-07-11 13:24:50.851 18610-18610/com.example.pop E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.pop, PID: 18610
android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.pop/com.example.pop.Profile}; have you declared this activity in your AndroidManifest.xml?
    at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:2014)
    at android.app.Instrumentation.execStartActivity(Instrumentation.java:1677)
    at android.app.Activity.startActivityForResult(Activity.java:4651)
    at androidx.fragment.app.FragmentActivity.startActivityForResult(FragmentActivity.java:676)
    at android.app.Activity.startActivityForResult(Activity.java:4609)
    at androidx.fragment.app.FragmentActivity.startActivityForResult(FragmentActivity.java:663)
    at android.app.Activity.startActivity(Activity.java:4970)
    at android.app.Activity.startActivity(Activity.java:4938)
    at com.example.pop.MainActivity.openProfile(MainActivity.java:43)
    at com.example.pop.MainActivity.access$100(MainActivity.java:10)
    at com.example.pop.MainActivity$2.onClick(MainActivity.java:35)
    at android.view.View.performClick(View.java:6612)
    at android.view.View.performClickInternal(View.java:6589)
    at android.view.View.access$3100(View.java:785)
    at android.view.View$PerformClick.run(View.java:25925)
    at android.os.Handler.handleCallback(Handler.java:873)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:201)
    at android.app.ActivityThread.main(ActivityThread.java:6823)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)