[Android] TTS Player 예제

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <Button
            android:id="@+id/btn_play"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="PLAY" />

        <Button
            android:id="@+id/btn_pause"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="WAIT" />

        <Button
            android:id="@+id/btn_stop"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="STOP" />
    </LinearLayout>

    <EditText
        android:id="@+id/et_input"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="안녕하세요!! 만나서 반갑습니다!"
        android:hint="재생할 텍스트 입력"
        android:maxLines="3" />

    <TextView
        android:id="@+id/tv_content"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:padding="10dp"
        android:scrollbars="vertical"
        android:text="입력한 텍스트가 출력되는 영역입니다."
        android:textColor="@android:color/black"
        android:textSize="16sp" />

</LinearLayout>

MainActivity.java

package com.example.ttsplayer;

import android.graphics.Color;
import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.speech.tts.UtteranceProgressListener;
import android.text.Spannable;
import android.text.SpannableString;
import android.text.style.BackgroundColorSpan;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import java.util.Locale;

public class MainActivity extends AppCompatActivity implements TextPlayer, View.OnClickListener {

    private final Bundle params = new Bundle();
    private final BackgroundColorSpan colorSpan = new BackgroundColorSpan(Color.YELLOW);
    private TextToSpeech tts;
    private Button playBtn;
    private Button pauseBtn;
    private Button stopBtn;
    private EditText inputEditText;
    private TextView contentTextView;
    private PlayState playState = PlayState.STOP;
    private Spannable spannable;
    private int standbyIndex = 0;
    private int lastPlayIndex = 0;

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

    private void initView() {
        playBtn = findViewById(R.id.btn_play);
        pauseBtn = findViewById(R.id.btn_pause);
        stopBtn = findViewById(R.id.btn_stop);
        inputEditText = findViewById(R.id.et_input);
        contentTextView = findViewById(R.id.tv_content);

        playBtn.setOnClickListener(this);
        pauseBtn.setOnClickListener(this);
        stopBtn.setOnClickListener(this);
    }

    private void initTTS() {
        params.putString(TextToSpeech.Engine.KEY_PARAM_UTTERANCE_ID, null);
        tts = new TextToSpeech(this, new TextToSpeech.OnInitListener() {
            @Override
            public void onInit(int state) {
                if (state == TextToSpeech.SUCCESS) {
                    tts.setLanguage(Locale.KOREAN);
                } else {
                    showState("TTS 객체 초기화 중 문제가 발생했습니다.");
                }
            }
        });

        tts.setOnUtteranceProgressListener(new UtteranceProgressListener() {
            @Override
            public void onStart(String s) {

            }

            @Override
            public void onDone(String s) {
                clearAll();
            }

            @Override
            public void onError(String s) {
                showState("재생 중 에러가 발생했습니다.");
            }

            @Override
            public void onRangeStart(String utteranceId, int start, int end, int frame) {
                changeHighlight(standbyIndex + start, standbyIndex + end);
                lastPlayIndex = start;
            }
        });
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.btn_play:
                startPlay();
                break;

            case R.id.btn_pause:
                pausePlay();
                break;

            case R.id.btn_stop:
                stopPlay();
                break;
        }
        showState(playState.getState());
    }

    @Override
    public void startPlay() {
        String content = inputEditText.getText().toString();
        if (playState.isStopping() && !tts.isSpeaking()) {
            setContentFromEditText(content);
            startSpeak(content);
        } else if (playState.isWaiting()) {
            standbyIndex += lastPlayIndex;
            startSpeak(content.substring(standbyIndex));
        }
        playState = PlayState.PLAY;
    }

    @Override
    public void pausePlay() {
        if (playState.isPlaying()) {
            playState = PlayState.WAIT;
            tts.stop();
        }
    }

    @Override
    public void stopPlay() {
        tts.stop();
        clearAll();
    }

    private void changeHighlight(final int start, final int end) {
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                spannable.setSpan(colorSpan, start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
            }
        });
    }

    private void setContentFromEditText(String content) {
        contentTextView.setText(content, TextView.BufferType.SPANNABLE);
        spannable = (SpannableString) contentTextView.getText();
    }

    private void startSpeak(final String text) {
        tts.speak(text, TextToSpeech.QUEUE_ADD, params, text);
    }

    private void clearAll() {
        playState = PlayState.STOP;
        standbyIndex = 0;
        lastPlayIndex = 0;

        if (spannable != null) {
            changeHighlight(0, 0); // remove highlight
        }
    }

    private void showState(final String msg) {
        Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_SHORT).show();
    }

    @Override
    protected void onPause() {
        if (playState.isPlaying()) {
            pausePlay();
        }
        super.onPause();
    }

    @Override
    protected void onResume() {
        if (playState.isWaiting()) {
            startPlay();
        }
        super.onResume();
    }

    @Override
    protected void onDestroy() {
        tts.stop();
        tts.shutdown();
        super.onDestroy();
    }
}

PlayState.java

package com.example.ttsplayer;

public enum PlayState {
    PLAY("재생 중"), WAIT("일시정지"), STOP("멈춤");

    private String state;

    PlayState(String state) {
        this.state = state;
    }

    public String getState() {
        return state;
    }

    public boolean isStopping() {
        return this == STOP;
    }

    public boolean isWaiting() {
        return this == WAIT;
    }

    public boolean isPlaying() {
        return this == PLAY;
    }
}

TextPlayer.java

package com.example.ttsplayer;

public interface TextPlayer {

    void startPlay();

    void pausePlay();

    void stopPlay();
}