GINPRO / SQLの窓と銀プログラマ

import java.io.Serializable;

public class WebData implements Serializable {

	String link;
	String name;

	@Override
	public String toString() {
		return name;
	}
}

<?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:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Main2Activity">
    <Button
        android:id="@+id/buttonReturn"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="戻る" />

    <TextView
        android:id="@+id/textViewLink"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="TextView"
        android:textSize="20sp"/>

    <TextView
        android:id="@+id/textViewName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="6dp"
        android:text="TextView"
        android:textSize="30sp"/>

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName"
        android:textSize="30sp"/>

    <Button
        android:id="@+id/buttonUpdate"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="更新"
        android:textSize="20sp"/>

</LinearLayout>

		listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

				// 行データを取得
				ArrayAdapter<WebData> arrayAdapter = (ArrayAdapter<WebData>) parent.getAdapter();
				WebData webData = arrayAdapter.getItem(position);

				// 行データを次画面に渡す
				Intent intent = new Intent(MainActivity.this,Main2Activity.class);
				intent.putExtra("DATA",webData);
				MainActivity.this.startActivityForResult(intent, 101);

				// 選択した行を保存
				MainActivity.this.position = position;

			}
		});

	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		super.onActivityResult(requestCode, resultCode, data);

		if ( requestCode == 101  ) {

			if ( resultCode == MainActivity.RESULT_OK ) {
				// ボタンの種類
				String result = data.getStringExtra("RESULT");
				if ( result.equals("終わったよ") ) {

				}
				if ( result.equals("更新したよ") ) {

					// 更新後データの取得
					WebData webData_update = (WebData) data.getSerializableExtra("DATA");

					WebData webData_listview = arrayAdapter.getItem(MainActivity.this.position);
					// 更新されたデータのセット
					webData_listview.name = webData_update.name;
					// 再表示
					listView.setAdapter(arrayAdapter);

				}
			}

		}

	}

		// 画面コントロールのインスタンス取得
		link = (TextView) Main2Activity.this.findViewById(R.id.textViewLink);
		name = (TextView) Main2Activity.this.findViewById(R.id.textViewName);
		editText = (EditText) Main2Activity.this.findViewById(R.id.editText);

		// データの取得
		Intent intent = Main2Activity.this.getIntent();
		WebData webData = (WebData) intent.getSerializableExtra("DATA");

		// データのセット
		link.setText(webData.link);
		name.setText(webData.name);
		editText.setText(webData.name);

		Button buttonReturn = (Button) Main2Activity.this.findViewById(R.id.buttonReturn);
		buttonReturn.setOnClickListener(new View.OnClickListener() {
			@Override
			public void onClick(View v) {

				Intent intent = new Intent();
				intent.putExtra("RESULT", "終わったよ");
				setResult(Main2Activity.RESULT_OK, intent);

				// 第二画面終了
				Main2Activity.this.finish();

			}
		});

		Button buttonUpdate = (Button) Main2Activity.this.findViewById(R.id.buttonUpdate);
		buttonUpdate.setOnClickListener(new View.OnClickListener() {
			@Override
			public void onClick(View v) {

				Intent intent = new Intent();
				intent.putExtra("RESULT", "更新したよ");

				Intent intentStart = Main2Activity.this.getIntent();
				WebData webData = (WebData) intentStart.getSerializableExtra("DATA");
				// 入力内容をセットする
				webData.name = editText.getText().toString();

				intent.putExtra("DATA", webData);
				setResult(Main2Activity.RESULT_OK, intent);

				// 第二画面終了
				Main2Activity.this.finish();

			}
		});

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:23.4.0'
    compile 'com.android.support.constraint:constraint-layout:1.0.2'
    testCompile 'junit:junit:4.12'
    compile 'com.squareup.okhttp3:okhttp:3.8.1'
    compile 'com.google.code.gson:gson:2.8.1'

}

<?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:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

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

</LinearLayout>

public class Weather {

	WebData[] pinpointLocations;

}

public class WebData {

	String link;
	String name;

	@Override
	public String toString() {
		return name;
	}
}

import android.os.AsyncTask;

import java.io.IOException;

import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class HttpAccess {

	private OkHttpClient okHttpClient;
	private String url;

	public interface OnAsyncTaskListener {
		abstract public void onAsyncTaskListener(String s);
	}

	public HttpAccess(String url) {
		this.okHttpClient = new OkHttpClient();
		this.url = url;
	}

	public void sendGet(final OnAsyncTaskListener listener ) {

		new AsyncTask<Void,Void,String>(){
			@Override
			protected String doInBackground(Void... params) {
				String result = "[\"error\"]";

				Request.Builder builder = new Request.Builder();
				builder.url(HttpAccess.this.url);
				Request request = builder.build();

				Response response = null;
				try {
					response = HttpAccess.this.okHttpClient.newCall(request).execute();
					result = response.body().string();
				}
				catch (IOException e) {
					e.printStackTrace();
				}

				return result;
			}

			// UI スレッド処理
			@Override
			protected void onPostExecute(String s) {
				super.onPostExecute(s);

				listener.onAsyncTaskListener(s);

			}
		}.execute();

	}

}

private ListView listView;
private ArrayAdapter<WebData> arrayAdapter;
private HttpAccess httpAccess;

listView = (ListView) MainActivity.this.findViewById(R.id.listView);
arrayAdapter = new ArrayAdapter<WebData>(MainActivity.this,android.R.layout.simple_list_item_1);

new HttpAccess("http://weather.livedoor.com/forecast/webservice/json/v1?city=270000")
	.sendGet(new HttpAccess.OnAsyncTaskListener() {
		@Override
		public void onAsyncTaskListener(String s) {

			Gson gson = new Gson();
			Weather weather = gson.fromJson(s, Weather.class);

			arrayAdapter.clear();
			arrayAdapter.addAll(weather.pinpointLocations);

		}
	});