Получение почты от Gmail в JAVA-приложение с помощью IMAP

Я столкнулся с подобной проблемой. Вот код, который поможет мне найти разрешение. Надеюсь, это вам поможет.

activity_main.xml

MainActivity.java

import android.app.ProgressDialog;
import android.content.Context;
import android.net.Uri;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

import com.google.android.gms.appindexing.Action;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class MainActivity extends AppCompatActivity {

    private ProgressDialog progress;
    /**
     * ATTENTION: This was auto-generated to implement the App Indexing API.
     * See https://g.co/AppIndexing/AndroidStudio for more information.
     */
 //   private GoogleApiClient client;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
  //      client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
    }

    public void sendGetRequest(View View) {
        new GetClass(this).execute();
    }

    @Override
    public void onStart() {
        super.onStart();

        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
 //       client.connect();
        Action viewAction = Action.newAction(
                Action.TYPE_VIEW, // TODO: choose an action type.
                "Main Page", // TODO: Define a title for the content shown.
                // TODO: If you have web page content that matches this app activity's content,
                // make sure this auto-generated web page URL is correct.
                // Otherwise, set the URL to null.
                Uri.parse("http://host/path"),
                // TODO: Make sure this auto-generated app deep link URI is correct.
                Uri.parse("android-app://com.example.gunawardena.get_post_demo/http/host/path")
        );
 //       AppIndex.AppIndexApi.start(client, viewAction);
    }

    @Override
    public void onStop() {
        super.onStop();

        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
        Action viewAction = Action.newAction(
                Action.TYPE_VIEW, // TODO: choose an action type.
                "Main Page", // TODO: Define a title for the content shown.
                // TODO: If you have web page content that matches this app activity's content,
                // make sure this auto-generated web page URL is correct.
                // Otherwise, set the URL to null.
                Uri.parse("http://host/path"),
                // TODO: Make sure this auto-generated app deep link URI is correct.
                Uri.parse("android-app://com.example.gunawardena.get_post_demo/http/host/path")
        );
      //  AppIndex.AppIndexApi.end(client, viewAction);
      // client.disconnect();
    }

    private class GetClass extends AsyncTask {

        private final Context context;

        public GetClass(Context c) {
            this.context = c;
        }

        protected void onPreExecute() {
            progress = new ProgressDialog(this.context);
            progress.setMessage("Loading Get Method.....");
            progress.show();
        }

        @Override
        protected Void doInBackground(String... params) {
            try {

                final TextView outputView = (TextView) findViewById(R.id.showOutput);
                URL url = new URL("https://dvlasearch.appspot.com/DvlaSearch?licencePlate=mt09nks&apikey=DvlaSearchDemoAccount");
                HttpURLConnection connection = (HttpURLConnection) url.openConnection();

                connection.setRequestMethod("GET");
                connection.setRequestProperty("USER-AGENT", "Mozilla/5.0");
                connection.setRequestProperty("ACCEPT-LANGUAGE", "en-US,en;0.5");

                int responseCode = connection.getResponseCode();

                final StringBuilder output = new StringBuilder("Request URL " + url);
                output.append(System.getProperty("line.separator") + "Response Code " + responseCode);
                output.append(System.getProperty("line.separator") + "Type " + "GET");
                BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
                String line = "";
                StringBuilder responseOutput = new StringBuilder();
                System.out.println("output===============" + br);
                while ((line = br.readLine()) != null) {
                    responseOutput.append(line);
                }
                br.close();

                output.append(System.getProperty("line.separator") + "Response " + System.getProperty("line.separator") + System.getProperty("line.separator") + responseOutput.toString());

                MainActivity.this.runOnUiThread(new Runnable() {

                    @Override
                    public void run() {
                        outputView.setText(output);
                        progress.dismiss();

                    }
                });

            } catch (MalformedURLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        }
    }
}

Выход на эмуляторе

HTH

Ссылки:

• Как отправить HTTP-запрос GET / POST в Java
• Java HttpURLConnection Пример для отправки запросов HTTP GET / POST
• Android POST и GET Request с использованием HttpURLConnection Tutorial