Audio Notification

//---------- MainActivity.java --------------

package com.example.texttospeech;

import androidx.appcompat.app.AppCompatActivity;

import android.annotation.SuppressLint;
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.graphics.drawable.Icon;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.Spinner;

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

public class MainActivity extends AppCompatActivity {

    Context context;
    EditText userTextInput;
    private static final String BE_URL = "https://api.backendless.com/B2CF8D9A-B15E-4F50-85F4-76F683DAF9A4/ACDA2C94-94A8-4DC8-82F0-06409BFEC05E/services/GCP/textToSpeech";
    private String beUrl;
    String res, textToSpeech;

    // Notification parameters declaration
    NotificationManager notificationManager;

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

    private void setPointer() {
        this.context = this;
        res = "";
        textToSpeech = "Something went wrong";
        // Setting up the languages list
        final Spinner spinner = (Spinner)findViewById(R.id.lngSelector);
        // Create an array adapter using the string array and a default spinner layout
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.languages, android.R.layout.simple_spinner_item);
        // Specify the layout to use when the list of choices appears
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        // Apply the adapter to the spinner
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(new CustomOnItemSelectedListener());

        // Creating notification channel and passing it to the notification manager
        notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
        createNotificationChannel("com.example.texttospeech.news", "NotifyDemo Sound Url", "Text To Speech sound MP3");

        // Adding a listener to the button
        findViewById(R.id.btnRun).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                textToSpeech = ((EditText)findViewById(R.id.usrTxtInput)).getText().toString().trim().replace(" ", "%20");
                String language = String.valueOf(spinner.getSelectedItem());
                getSoundUrl(textToSpeech, getLangCode(language));
                // With Alert Dialog implementation
                AlertDialog.Builder alertBuilder = new AlertDialog.Builder(context);
                alertBuilder.setMessage("Press the OK button to play the audio file").setTitle("Play sound file");
                alertBuilder.setPositiveButton("PLAY", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        Intent resultIntent = new Intent(context, ResultActivity.class);
                        resultIntent.putExtra("resUrl", res);
                        resultIntent.putExtra("resText", textToSpeech);
                        startActivity(resultIntent);
                    }
                });
                AlertDialog dialog = alertBuilder.create();
                dialog.show();
            }
        });
    }

    protected void createNotificationChannel(String id, String name, String description) {
        int importance = NotificationManager.IMPORTANCE_LOW;
        NotificationChannel channel = new NotificationChannel(id, name, importance);
        channel.setDescription(description);
        channel.enableLights(true);
        channel.setLightColor(Color.RED);
        channel.enableVibration(true);
        channel.setVibrationPattern(new long[]{100, 200, 300, 400, 500, 400, 300, 200, 400});
        notificationManager.createNotificationChannel(channel);
    }

    protected void sendNotification() {
        int notificationID = 101;
        Intent resultIntent = new Intent(this, ResultActivity.class);
        resultIntent.putExtra("resUrl", res);
        resultIntent.putExtra("resText", textToSpeech);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, resultIntent, PendingIntent.FLAG_UPDATE_CURRENT);
        String channelID = "com.example.texttospeech.news";
        final Icon icon = Icon.createWithResource(MainActivity.this, android.R.drawable.ic_dialog_info);
        Notification.Action action = new Notification.Action.Builder(icon, "Play", pendingIntent).build();
        Notification notification = new Notification.Builder(MainActivity.this, channelID)
                .setContentTitle("Your MP3 file link")
                .setContentText("voice1.mp3")
                .setContentIntent(pendingIntent)
                .setActions(action)
                .setSmallIcon(android.R.drawable.ic_dialog_info).setChannelId(channelID).build();
        notificationManager.notify(notificationID, notification);
    }

    private String getLangCode(String language) {
        String lngCode = "en"; // Default language
        switch (language) {
            case "English":
                lngCode  = "en";
                break;
            case "German":
                lngCode  = "de";
                break;
            case "Spanish":
                lngCode  = "es";
                break;
            case "Dutch":
                lngCode  = "nl";
                break;
            case "French":
                lngCode  = "fr";
                break;
            case "Arabic":
                lngCode  = "ar";
                break;
            case "Hebrew":
                lngCode  = "he";
                break;
            default:
                break;
        }
        return lngCode;
    }

    @SuppressLint("StaticFieldLeak")
    private void getSoundUrl(String textToSpeech, String language) {
        beUrl = BE_URL + "?text=" + textToSpeech + "&lang=" + language;
        new AsyncTask<String, Void, String>() {

            @Override
            protected String doInBackground(String... strings) {
                HttpURLConnection urlConnection = null;
                String result = "";
                try {
                    URL url = new URL(beUrl);
                    urlConnection = (HttpURLConnection)url.openConnection();
                    int statusCode = urlConnection.getResponseCode();
                    if(statusCode == 200) {
                        InputStream inputStream = new BufferedInputStream(urlConnection.getInputStream());
                        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                        String line;
                        while((line = bufferedReader.readLine()) != null) {
                            result += line;
                        }
                        inputStream.close();
                        return result;
                    } else {
                        Log.e("Network Error", "doInBackground: The request responded with code " + statusCode);
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                    assert urlConnection != null;
                    urlConnection.disconnect();
                }
                return result;
            }

            @Override
            protected void onPostExecute(String be_response) {
                res = be_response;
                sendNotification();
            }
        }.execute();
    }

    class CustomOnItemSelectedListener implements AdapterView.OnItemSelectedListener {

        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    }
}

//----------------- ResultActivity.java ---------------------

package com.example.texttospeech;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

import java.io.IOException;

public class ResultActivity extends AppCompatActivity {

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

    private void setPointer() {
        String audioUrl = getIntent().getStringExtra("resUrl");
        String text = getIntent().getStringExtra("resText");
        ((TextView)findViewById(R.id.txtLine)).setText(text.replace("%20", " "));
        playSound(audioUrl);
    }

    private void playSound(String myUrl) {
        final MediaPlayer mediaPlayer = new MediaPlayer();
        try {
            Log.e("myUrl", "playSound: " + myUrl.replace("\"", ""));
            mediaPlayer.setDataSource(myUrl.replace("\"", ""));
            mediaPlayer.prepareAsync();
            mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                @Override
                public void onPrepared(MediaPlayer mp) {
                    mp.start();
                }
            });
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

////////////////////// XML Layouts ////////////////////
//--------------- 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">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <TextView
            android:id="@+id/textView"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/title"
            android:textSize="30sp"
            android:textColor="@color/colorPrimary"
            android:textStyle="bold"
            android:gravity="center"
            android:layout_marginTop="80dp"/>

        <EditText
            android:id="@+id/usrTxtInput"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_weight="8"
            android:ems="10"
            android:inputType="textPersonName"
            android:layout_margin="30dp"
            android:text="@string/text_input_box" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_weight="10"
            android:layout_margin="30dp"
            android:gravity="center"
            android:orientation="horizontal">

            <TextView
                android:id="@+id/textView3"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_weight="2"
                android:textSize="24sp"
                android:text="@string/choose_language"
                tools:ignore="NestedWeights" />
            <Spinner
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_weight="3"
                android:id="@+id/lngSelector" />
        </LinearLayout>
        <Button
            android:layout_width="wrap_content"
            android:layout_marginBottom="60dp"
            android:padding="20sp"
            android:layout_gravity="center"
            android:layout_height="wrap_content"
            android:textSize="24sp"
            android:id="@+id/btnRun"
            android:text="@string/speak"
            style="@style/Widget.AppCompat.Button.Colored"/>

    </LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

//----------------- activity_result.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=".ResultActivity">

    <TextView
        android:id="@+id/txtLine"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:text="Success"
        android:textSize="36sp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

//------------------ strings.xml (from the values library) ------------

<resources>
    <string name="app_name">Text To Speech</string>
    <string name="speak">Speak</string>
    <string name="choose_language">Choose a language</string>
    <string name="text_input_box">Put your text here...</string>
    <string name="title">Text To Speech App</string>
    <string-array name="languages">
        <item>English</item>
        <item>German</item>
        <item>Spanish</item>
        <item>Dutch</item>
        <item>French</item>
        <item>Arabic</item>
        <item>Hebrew</item>
    </string-array>
</resources>