我正在尝试制作一个可以播放，暂停，播放下一首歌曲和播放上一首歌曲的应用。我使用两种方式：-一种使用按钮，另一种使用语音转文本。 按钮一个工作正常。在文本语音播放，播放，播放前一首歌曲和播放下一首歌曲的过程中，工作正常，但暂停不起作用。
package com.example.musicaldelight;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Bundle;
import android.speech.RecognitionListener;
import android.speech.RecognizerIntent;
import android.speech.SpeechRecognizer;
import android.speech.tts.TextToSpeech;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
public class PlayMusic extends AppCompatActivity {
private RelativeLayout parentRelativeLayout;
private TextToSpeech mytexttospeech;
private SpeechRecognizer speechRecognition;
private ImageView playPauseBtn, nextBtn, previousBtn;
private TextView songNameTxt;
private ImageView imageView;
private RelativeLayout lowerRelativeLayout;
private MediaPlayer mymMediaPlayer;
private int position;
private ArrayList<File> mySongs;
private String mSongName;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.play_music);
playPauseBtn=findViewById(R.id.play_pause_btn);
nextBtn=findViewById(R.id.next_btn);
previousBtn=findViewById(R.id.previous_btn);
imageView=findViewById(R.id.logo);
lowerRelativeLayout=findViewById(R.id.lower);
songNameTxt=findViewById(R.id.songName);
validateReceiveValuesAndStartPlaying();
imageView.setImageResource(R.drawable.logo);
playPauseBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
playPauseSong();
}
});
previousBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(mymMediaPlayer.getCurrentPosition()>0)
{
playPreviousSong();
}
}
});
nextBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(mymMediaPlayer.getCurrentPosition()>0)
{
playNextSong();
}
}
});
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_MAX_RESULTS,1);
speechRecognition.startListening(intent);
**initializeTextToSpeech();
initializeSpeechRecognizer();**
}
});
**initializeTextToSpeech();
initializeSpeechRecognizer();**
}
private void validateReceiveValuesAndStartPlaying()
{
releaseMediaPlayer();
Intent intent=getIntent();
Bundle bundle=intent.getExtras();
mySongs=(ArrayList)bundle.getParcelableArrayList("song");
mSongName=mySongs.get(position).getName();
String songName=intent.getStringExtra("name");
songNameTxt.setText(songName);
songNameTxt.setSelected(true);
position=bundle.getInt("position",0);
Uri uri=Uri.parse(mySongs.get(position).toString());
mymMediaPlayer=MediaPlayer.create(PlayMusic.this,uri);
mymMediaPlayer.start();
}
private void releaseMediaPlayer() {
if (mymMediaPlayer != null) {
mymMediaPlayer.release();
mymMediaPlayer = null;
}
}
public void playPauseSong()
{
imageView.setBackgroundResource(R.drawable.four);
if(mymMediaPlayer.isPlaying())
{
playPauseBtn.setImageResource(R.drawable.play);
mymMediaPlayer.pause();
}
else
{
playPauseBtn.setImageResource(R.drawable.pause);
mymMediaPlayer.start();
imageView.setBackgroundResource(R.drawable.four);
}
}
@Override
public void onBackPressed() {
releaseMediaPlayer();
super.onBackPressed();
}
public void playNextSong()
{
mymMediaPlayer.pause();
mymMediaPlayer.stop();
mymMediaPlayer.release();
position=((position+1)%mySongs.size());
Uri uri=Uri.parse(mySongs.get(position).toString());
mymMediaPlayer=MediaPlayer.create(PlayMusic.this,uri);
mSongName=mySongs.get(position).toString();
songNameTxt.setText(mSongName);
mymMediaPlayer.start();
imageView.setBackgroundResource(R.drawable.three);
if(mymMediaPlayer.isPlaying())
{
playPauseBtn.setImageResource(R.drawable.pause);
}
else
{
playPauseBtn.setImageResource(R.drawable.play);
imageView.setBackgroundResource(R.drawable.five);
}
}
public void playPreviousSong()
{
mymMediaPlayer.pause();
mymMediaPlayer.stop();
mymMediaPlayer.release();
position=((position-1)<0?(mySongs.size()-1):(position-1));
Uri uri=Uri.parse(mySongs.get(position).toString());
mymMediaPlayer=MediaPlayer.create(PlayMusic.this,uri);
mSongName=mySongs.get(position).toString();
songNameTxt.setText(mSongName);
mymMediaPlayer.start();
imageView.setBackgroundResource(R.drawable.two);
if(mymMediaPlayer.isPlaying())
{
playPauseBtn.setImageResource(R.drawable.pause);
}
else
{
playPauseBtn.setImageResource(R.drawable.play);
imageView.setBackgroundResource(R.drawable.five);
}
}
public void initializeSpeechRecognizer() {
if(SpeechRecognizer.isRecognitionAvailable(this))
{
speechRecognition=SpeechRecognizer.createSpeechRecognizer(this);
speechRecognition.setRecognitionListener(new RecognitionListener() {
@Override
public void onReadyForSpeech(Bundle params) {
}
@Override
public void onBeginningOfSpeech() {
}
@Override
public void onRmsChanged(float rmsdB) {
}
@Override
public void onBufferReceived(byte[] buffer) {
}
@Override
public void onEndOfSpeech() {
}
@Override
public void onError(int error) {
}
@Override
public void onResults(Bundle results) {
List<String> result=results.getStringArrayList(SpeechRecognizer.RESULTS_RECOGNITION);
//recognizer returns multiple results
processResult(result.get(0));
//pick result with highest score
}
@Override
public void onPartialResults(Bundle partialResults) {
}
@Override
public void onEvent(int eventType, Bundle params) {
}
});
}
}
public void processResult(String command) {
command=command.toLowerCase();
if(command.indexOf("play")!=-1){
playPauseSong();
}
if(command.indexOf("pause")!=-1){
playPauseSong();
}
if(command.indexOf("next")!=-1){
playNextSong();
}
if(command.indexOf("previous")!=-1){
playPreviousSong();
}
}
public void initializeTextToSpeech() {
mytexttospeech=new TextToSpeech(this, new TextToSpeech.OnInitListener() {
@Override
public void onInit(int status) {
if(mytexttospeech.getEngines().size()==0)
{
Toast.makeText(PlayMusic.this,"There is no TTS engine on your device",Toast.LENGTH_LONG).show();
finish();
}
else
{
mytexttospeech.setLanguage(Locale.US);
}
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onPause() {
super.onPause();
mytexttospeech.shutdown();
}
@Override
protected void onDestroy() {
//Close the Text to Speech Library
if(mytexttospeech != null) {
mytexttospeech.stop();
mytexttospeech.shutdown();
}
super.onDestroy();
}
}
我已经标记了一个区域
initializeTextToSpeech（）;
initializeSpeechRecognizer（）;
我认为错误是由于此代码引起的。我把它放了两次。我无法理解将其放置在何处。但是也许错误是由于其他原因造成的。请任何建议。如果需要其他文件，我将其上传。
谢谢