文字转语音在 Android Studio 中无法正常工作

Question

I have recently created a simple project in android studio using speech recognition and text to speech but the problem is that the text to speech doesn't speak the given line on starting the app for the first time but after this event it works very properly. Like when I start the app in the below code I have added the line to welcome the user but tts doesn't speak and then when I press the recognize button the app recognizes the sentence and also speaks correctly. Why is it so? It seems quite weird. I am providing the code below please do check it and tell me if I am making some mistake as soon as possible.

This is my Java code:

package com.maitreyastudio.ai;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import android.Manifest;
import android.annotation.SuppressLint;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.provider.Settings;
import android.speech.RecognitionListener;
import android.speech.RecognizerIntent;
import android.speech.SpeechRecognizer;
import android.speech.tts.TextToSpeech;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.GridLayout;
import android.widget.TextView;


import com.chaquo.python.PyObject;
import com.chaquo.python.Python;
import com.chaquo.python.android.AndroidPlatform;
import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.gms.tasks.Task;

import org.w3c.dom.Text;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Locale;

import static android.Manifest.permission.ACCESS_FINE_LOCATION;
import static android.Manifest.permission.READ_EXTERNAL_STORAGE;
import static android.Manifest.permission.RECORD_AUDIO;
import static android.Manifest.permission.WRITE_EXTERNAL_STORAGE;


public class MainActivity extends AppCompatActivity {


    private Button btnRecognize;
    private SpeechRecognizer speechRecognizer;
    private TextToSpeech textToSpeech;
    private EditText ET_ShowRecognized;
    String locality;
    private Intent intent;
    private String ET_ShowRecognizedText;
    private String ProcessingText;
    private ArrayList voices;
    private FusedLocationProviderClient fusedLocationProviderClient;
    Geocoder geocoder;
    /*Python py;
    PyObject pyobj;
    PyObject obj;
    String currentDate;
    String currentTime;*/


    @SuppressLint({"SetTextI18n", "ClickableViewAccessibility", "MissingPermission"})
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ActivityCompat.requestPermissions(this, new String[]{RECORD_AUDIO, WRITE_EXTERNAL_STORAGE, READ_EXTERNAL_STORAGE, ACCESS_FINE_LOCATION}, PackageManager.PERMISSION_GRANTED);


        ET_ShowRecognized = findViewById(R.id.ET_ShowRecognized);
        btnRecognize = findViewById(R.id.btnRecognize);




        /*fusedLocationProviderClient.getLastLocation().addOnCompleteListener(new OnCompleteListener<Location>() {
            @Override
            public void onComplete(@NonNull Task<Location> task) {

                Location location = task.getResult();
                if(location != null){

                    geocoder = new Geocoder(MainActivity.this, Locale.getDefault());
                    try {

                        List<Address> address = geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
                        locality = address.get(0).getLocality();

                    } catch (IOException e) {
                        ;
                    }

                }
            }
        });


        if(!Python.isStarted()){

            Python.start(new AndroidPlatform(this));

        }
        py = Python.getInstance();
        pyobj = py.getModule("WolframAlpha");
        obj = pyobj.callAttr("main", locality);*/


        textToSpeech = new TextToSpeech(getApplicationContext(), new TextToSpeech.OnInitListener() {
            @Override
            public void onInit(int i) {
                if (i == TextToSpeech.SUCCESS) {

                    textToSpeech.setLanguage(Locale.ENGLISH);


                }

            }
        });

        textToSpeech.speak("Hi you succesfully ran me.", TextToSpeech.QUEUE_FLUSH, null, null);


        //currentDate = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault()).format(new Date());
        //currentTime = new SimpleDateFormat("HH:mm:ss", Locale.getDefault()).format(new Date());
        //textToSpeech.speak("Hi! I am your personal assistant. Today date is something something ", TextToSpeech.QUEUE_FLUSH, null, null);
        //Speak("Today's weather forecast for the current location is " + obj.toString());


        intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
        intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);

        speechRecognizer = SpeechRecognizer.createSpeechRecognizer(this);
        speechRecognizer.setRecognitionListener(new RecognitionListener() {
            @Override
            public void onReadyForSpeech(Bundle bundle) {

            }

            @Override
            public void onBeginningOfSpeech() {

            }

            @Override
            public void onRmsChanged(float v) {

            }

            @Override
            public void onBufferReceived(byte[] bytes) {

            }

            @Override
            public void onEndOfSpeech() {

            }

            @Override
            public void onError(int i) {

            }

            @Override
            public void onResults(Bundle bundle) {
                ArrayList<String> mathches = bundle.getStringArrayList(SpeechRecognizer.RESULTS_RECOGNITION);

                if (mathches != null) {

                    ET_ShowRecognized.setText(mathches.get(0));
                    process();


                }
            }

            @Override
            public void onPartialResults(Bundle bundle) {

            }

            @Override
            public void onEvent(int i, Bundle bundle) {

            }
        });


        btnRecognize.setOnTouchListener(new View.OnTouchListener() {

            @Override
            public boolean onTouch(View view, MotionEvent motionEvent) {

                switch (motionEvent.getAction()) {

                    case MotionEvent.ACTION_UP:
                        speechRecognizer.stopListening();

                        break;

                    case MotionEvent.ACTION_DOWN:
                        ET_ShowRecognized.setText(null);
                        ET_ShowRecognized.setText("Listening...");
                        speechRecognizer.startListening(intent);
                        break;
                    default:
                        break;
                }

                return false;
            }
        });

        textToSpeech.speak("Hi! Seems good to meet you.", TextToSpeech.QUEUE_FLUSH, null, null);
    }

    public void process() {

        ProcessingText = ET_ShowRecognized.getText().toString().toLowerCase();

        switch (ProcessingText) {

            case ("hello"):
                textToSpeech.speak("Hello! Hope all is going fine.", TextToSpeech.QUEUE_FLUSH, null, null);
                break;

            case ("hi"):
                textToSpeech.speak("Hi! I hope all is well.", TextToSpeech.QUEUE_FLUSH, null, null);
                break;


            case ("what is your name"):
                textToSpeech.speak("My name is assistant.", TextToSpeech.QUEUE_FLUSH, null, null);
                break;


            case ("bye"):
                finish();
                System.exit(0);

            default:
                textToSpeech.speak(ProcessingText, TextToSpeech.QUEUE_FLUSH, null, null);
                break;
        }

    }

}

And this is my XML code

<?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">

    <Button
        android:id="@+id/btnRecognize"
        style="@style/Widget.AppCompat.Button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/recognize"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/ET_ShowRecognized"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName"
        android:hint="@string/you_will_see_recognized_text_here"
        app:layout_constraintBottom_toTopOf="@+id/btnRecognize"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

Please help me as soon as possible.

Thank You

Answer 1

You can try by creating an application class and initialize your textToSpeech engine in it so that it starts initializing on app launch.

public class MyApp extends Application {
    private static MyApp instance = null;
    private TextToSpeech t1;

    public static MyApp getInstance() {
        return instance;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        instance = this;

        t1 = new TextToSpeech(this, new TextToSpeech.OnInitListener() {
            @Override
            public void onInit(int i) {
                if (i == TextToSpeech.SUCCESS) {
                    
                }
            }
        });
    }

    public TextToSpeech getT1() {
        return t1;
    }
}

and than use that in your activity.

Answer 2

The reason it didn't work before is the same reason DB377 said. It's because the initialization of the tts is asynchronous and onInit is only called when that process is complete. Execution doesn't necessarily happen line-by-line.

You can change your code as follows:

// THIS RUNS FIRST
textToSpeech = new TextToSpeech(getApplicationContext(), new TextToSpeech.OnInitListener() {

        // THIS RUNS THIRD!
        @Override
        public void onInit(int i) {
            if (i == TextToSpeech.SUCCESS) {

                textToSpeech.setLanguage(Locale.ENGLISH);

                // NEW LOCATION
                textToSpeech.speak("Hi you succesfully ran me.", TextToSpeech.QUEUE_FLUSH, null, null);


            }

        }
    });

    // OLD LOCATION (THIS RUNS SECOND)