異步請求數據加跳轉傳圖片

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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="com.example.com.zuoye.MainActivity"
    android:orientation="vertical">

   <ListView
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:id="@+id/lv"></ListView>

</LinearLayout>

MainActivity:

package com.example.com.zuoye;

import android.content.Intent;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;

import com.google.gson.Gson;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;

public class MainActivity extends AppCompatActivity {
private String getData="http://www.yulin520.com/a2a/impressApi/news/mergeList?pageSize=10&page=1";
    private ListView lv;
    private List<ReqBean.DataBean> data;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lv = findViewById(R.id.lv);
        mytask mytask = new mytask();
        mytask.execute();



        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                Intent intent = new Intent(MainActivity.this, Second.class);

                intent.putExtra("img",data.get(i).getImg());
                startActivity(intent);
            }
        });

    }

    class mytask extends AsyncTask<String,Void,String>{

        @Override
        protected String doInBackground(String... strings) {

            try {
                URL url=new URL(getData);
                HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.setReadTimeout(5000);
                urlConnection.setConnectTimeout(5000);
                        if (urlConnection.getResponseCode()==200){
                            InputStream inputStream = urlConnection.getInputStream();
                            return statemtostring(inputStream);

                        }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            Gson gson = new Gson();
            ReqBean reqBean = gson.fromJson(s, ReqBean.class);

            data = reqBean.getData();
            MyAdapter myAdapter = new MyAdapter(MainActivity.this, data);
            lv.setAdapter(myAdapter);



        }
    }

    public String statemtostring(InputStream inputStream){
        StringBuilder builder = new StringBuilder();
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
        String str;
        try {
            while((str=reader.readLine())!=null){
            builder.append(str);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return builder.toString();
    }


}

注：適配器一樣

跳轉的第二個頁面：

佈局文件：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="com.example.com.zuoye.Second">


    <ImageView
        android:layout_width="180dp"
        android:layout_height="180dp"
        android:id="@+id/image"/>
</RelativeLayout>

第二個頁面：

package com.example.com.zuoye;

import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;

import com.google.gson.Gson;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class Second extends AppCompatActivity {
    private ImageView image;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
        //找控件
        image = findViewById(R.id.image);


        Intent intent = getIntent();
        String img = intent.getStringExtra("img");

        mytask mytask = new mytask();
        mytask.execute(img);



    }

    class mytask extends AsyncTask<String,Void,Bitmap> {

        @Override
        protected Bitmap doInBackground(String... strings) {

            try {

                URL url=new URL(strings[0]);
                HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.setReadTimeout(5000);
                urlConnection.setConnectTimeout(5000);
                if (urlConnection.getResponseCode()==200){
                    InputStream inputStream = urlConnection.getInputStream();
                    //需要使用BitmapFactory 將inputStream 轉換爲圖片格式
                    Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
                    return bitmap;
                }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Bitmap s) {
            super.onPostExecute(s);

            image.setImageBitmap(s);

        }
    }



}