java - MediaPlayer 在 ListView 中选择新歌曲时停止当前歌曲
问题描述
我正在使用ListView
. 当我在 上单击一首歌曲时MainActivity
,它会打开一个nowplaying
活动并开始播放一首歌曲,但如果我返回ListView
并单击一首新歌曲,则新歌曲开始播放,而前一首歌曲仍在播放,因此两首歌曲都在同时。
我如何做到这一点,当点击一首新歌时,上一首歌曲停止并且新歌曲开始?下面是我的代码MainActivity
public class nowPlaying extends AppCompatActivity implements View.OnClickListener {
Button rewindButton, pauseAndPlayButton, fastForwardButton;
TextView songNameID, artistNameID, details, detailsText;
ImageView musicLogo;
SeekBar seekBar;
public static MediaPlayer mediaPlayer;
public Runnable runnable;
public Handler handler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_now_playing);
TextView nowPlayingID = findViewById(R.id.now_playing_id);
songNameID = findViewById(R.id.song_name_id);
artistNameID = findViewById(R.id.artist_name_id);
rewindButton = findViewById(R.id.rewind_button);
pauseAndPlayButton = findViewById(R.id.pause_and_play_button);
fastForwardButton = findViewById(R.id.fast_forward_button);
detailsText = findViewById(R.id.details_text);
details = findViewById(R.id.details_id);
seekBar = findViewById(R.id.seekbar_id);
musicLogo = findViewById(R.id.music_logo);
handler = new Handler();
nowPlayingID.setText(R.string.now_playing);
rewindButton.setText("<<");
pauseAndPlayButton.setText(R.string.ii);
fastForwardButton.setText(">>");
details.setText(R.string.about_song);
String nameSong = getIntent().getStringExtra("name");
String nameArtist = getIntent().getStringExtra("artist");
if (nameSong.equals("Shape of you") && nameArtist.equals("ed sheeran")) {
songNameID.setText(nameSong);
artistNameID.setText(nameArtist);
detailsText.setText(R.string.details_ed_sheeran);
musicLogo.setImageResource(R.drawable.shape_of_you);
mediaPlayer = MediaPlayer.create(this, R.raw.sheeran);
rewindButton.setOnClickListener(this);
pauseAndPlayButton.setOnClickListener(this);
fastForwardButton.setOnClickListener(this);
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
seekBar.setMax(mediaPlayer.getDuration());
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release();
}
else {
mediaPlayer.start();
changeSeekbar();
}
}
});
}
else if (nameSong.equals("Friends") && nameArtist.equals("marshmello & anne-marie")) {
songNameID.setText(nameSong);
artistNameID.setText(nameArtist);
detailsText.setText(R.string.details_marshmello);
musicLogo.setImageResource(R.drawable.marshmello);
mediaPlayer = MediaPlayer.create(this, R.raw.marshmello);
rewindButton.setOnClickListener(this);
pauseAndPlayButton.setOnClickListener(this);
fastForwardButton.setOnClickListener(this);
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
seekBar.setMax(mediaPlayer.getDuration());
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release();
}
else {
mediaPlayer.start();
changeSeekbar();
}
}
});
}
else if (nameSong.equals("L'Hiver Indien") && nameArtist.equals("baloji")) {
songNameID.setText(nameSong);
artistNameID.setText(nameArtist);
detailsText.setText(R.string.details_baloji);
musicLogo.setImageResource(R.drawable.baloji);
mediaPlayer = MediaPlayer.create(this, R.raw.baloji);
rewindButton.setOnClickListener(this);
pauseAndPlayButton.setOnClickListener(this);
fastForwardButton.setOnClickListener(this);
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
seekBar.setMax(mediaPlayer.getDuration());
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release();
}
else {
mediaPlayer.start();
changeSeekbar();
}
}
});
}
else if (nameSong.equals("Ye") && nameArtist.equals("burna boy")) {
songNameID.setText(nameSong);
artistNameID.setText(nameArtist);
detailsText.setText(R.string.details_burna);
musicLogo.setImageResource(R.drawable.burna);
mediaPlayer = MediaPlayer.create(this, R.raw.burna);
rewindButton.setOnClickListener(this);
pauseAndPlayButton.setOnClickListener(this);
fastForwardButton.setOnClickListener(this);
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
seekBar.setMax(mediaPlayer.getDuration());
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release();
}
else {
mediaPlayer.start();
changeSeekbar();
}
}
});
}
else if (nameSong.equals("What lovers do") && nameArtist.equals("maroon 5 ft. sza")) {
songNameID.setText(nameSong);
artistNameID.setText(nameArtist);
detailsText.setText(R.string.details_maroon);
musicLogo.setImageResource(R.drawable.maroon_five);
mediaPlayer = MediaPlayer.create(this, R.raw.maroon);
rewindButton.setOnClickListener(this);
pauseAndPlayButton.setOnClickListener(this);
fastForwardButton.setOnClickListener(this);
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
seekBar.setMax(mediaPlayer.getDuration());
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release();
}
else {
mediaPlayer.start();
changeSeekbar();
}
}
});
}
else if (nameSong.equals("Live in the moment") && nameArtist.equals("portugal. the man")) {
songNameID.setText(nameSong);
artistNameID.setText(nameArtist);
detailsText.setText(R.string.details_portugal);
musicLogo.setImageResource(R.drawable.portugal_man);
mediaPlayer = MediaPlayer.create(this, R.raw.portugal);
rewindButton.setOnClickListener(this);
pauseAndPlayButton.setOnClickListener(this);
fastForwardButton.setOnClickListener(this);
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
seekBar.setMax(mediaPlayer.getDuration());
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release();
}
else {
mediaPlayer.start();
changeSeekbar();
}
}
});
}
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
if (b) {
mediaPlayer.seekTo(i);
}
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
}
public void changeSeekbar() {
seekBar.setProgress(mediaPlayer.getCurrentPosition());
if (mediaPlayer.isPlaying()) {
runnable = new Runnable() {
@Override
public void run() {
changeSeekbar();
}
};
handler.postDelayed(runnable, 1000);
}
}
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.pause_and_play_button:
if (mediaPlayer.isPlaying()) {
mediaPlayer.pause();
pauseAndPlayButton.setText(">");
}
else {
mediaPlayer.start();
pauseAndPlayButton.setText("||");
changeSeekbar();
}
break;
case R.id.fast_forward_button:
mediaPlayer.seekTo(mediaPlayer.getCurrentPosition() + 5000);
break;
case R.id.rewind_button:
mediaPlayer.seekTo(mediaPlayer.getCurrentPosition() - 5000);
break;
}
}
}
解决方案
切换到新的音频文件时,需要先将 mediaPlayer 指针/变量设为 null,然后再分配新的音频源
public void stop() {
if (mp != null) {
mp.release();
mp = null;
}
}
public void play(int rid) {
stop();
mp = MediaPlayer.create(this, rid);
mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mediaPlayer) {
stop();
}
});
mp.start();
}
推荐阅读
- python - 列表元素的条件选择
- python - Statsmodels-AIC- 如何计算 Delta AIC(已解决)
- javascript - Vue Firebase firebase/auth 不工作,但 firebase/firestore 工作正常。“身份验证不是函数”
- apollo - 如何将带有 Composition API 的 Apollo 加载到 Vue 3 中?
- haskell - 在评估表达式的类型时,是否可以指示 ghci 使用具体类型作为约束?
- mongodb - 如何在猫鼬中仅列出匹配的子文档
- python - Pandas 拆分列将每个项目迭代到两个新的对列
- prometheus - Grafana/Prometheus 节点导出器无数据
- sql - 是否有要求填写一列的 SQL 查询?
- javascript - 将元素附加到 Null