实际上我有2个活动，在主要活动中我使用回收视图显示所有歌曲并在其上设置onClickListner，当有人点击它时，它启动一个新活动（MediaPlayer Activity）并开始播放歌曲以及媒体控制（如paly，pause和seekBar）。
但是当我回到主要活动并点击一个按钮（基本上再次进入MediaPlayer活动）时，所有mediaPlayer和seekBar进度都消失了（播放，暂停，下一个和上一个按钮）没有响应点击次数。
这是我开始MediaPlayer活动的地方：
@Override
public void onBindViewHolder(final MyViewHolder holder, final int position) {
holder.Song.setText(mData.get(position).title);
holder.Artist.setText(mData.get(position).artist);
Glide.with(mcontext).load(mData.get(position).imagePath).
placeholder(R.drawable.unknown_art).into(holder.PhotoId);
holder.Options.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(mcontext, "You clicked on options", Toast.LENGTH_SHORT).show();
}
});
holder.RL.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(mcontext, MediaPlayerActivity.class);
intent.putExtra("songPosition",position);
mcontext.startActivity(intent);
}
});
这些是MediaPlayerActivity中的代码：
public class MediaPlayerActivity extends AppCompatActivity {
static MediaPlayer mediaPlayer=null;
static int pos=0;
SeekBar seekBar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_media_player);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
Intent intent = getIntent();
pos = intent.getIntExtra("songPosition",pos);
seekBar = (SeekBar)findViewById(R.id.seekBar);
Button next = (Button)findViewById(R.id.button_1);
Button previous = (Button)findViewById(R.id.button_2);
final Button play_pause = (Button)findViewById(R.id.button_3);
final TextView info = (TextView)findViewById(R.id.songInfo);
info.setText(VerticalRecyclerViewAdapter.mData.get(pos).title);
if(mediaPlayer!=null&&mediaPlayer.isPlaying()){
mediaPlayer.stop();
mediaPlayer.reset();
mediaPlayer.release();
}
playMedia(pos);
next.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try {
mediaPlayer.stop();
mediaPlayer.reset();
mediaPlayer.release();
playMedia(++pos);
info.setText(VerticalRecyclerViewAdapter.mData.get(pos).title);
}catch (IndexOutOfBoundsException e){
Toast.makeText(MediaPlayerActivity.this,"Already the last song!!!",Toast.LENGTH_SHORT).show();
}
}
});
previous.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try {
mediaPlayer.stop();
mediaPlayer.reset();
mediaPlayer.release();
playMedia(--pos);
info.setText(VerticalRecyclerViewAdapter.mData.get(pos).title);
}catch (IndexOutOfBoundsException e){
Toast.makeText(MediaPlayerActivity.this,"Already the first song!!!",Toast.LENGTH_SHORT).show();
}
}
});
play_pause.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(mediaPlayer!=null&&mediaPlayer.isPlaying()){
play_pause.setText(R.string.mp_play);
mediaPlayer.pause();
}
else{
play_pause.setText(R.string.mp_Pause);
mediaPlayer.start();
}
}
});
}
public void playMedia(int pos){
try {
mediaPlayer = new MediaPlayer();
mediaPlayer.setDataSource(VerticalRecyclerViewAdapter.mData.get(pos).songPath);
mediaPlayer.prepareAsync();
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
seekBar.setProgress(0);
seekBar.setMax(mp.getDuration());
mediaPlayer.start();
}
});
} catch (IOException e) {
e.printStackTrace();
}
setSeekbarProgress();
onSeekbarChange();
playNext();
}
public void playNext(){
mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
try {
mediaPlayer.release();
playMedia(++MediaPlayerActivity.pos);
}catch (IndexOutOfBoundsException e){
Toast.makeText(MediaPlayerActivity.this, "Already the last song", Toast.LENGTH_SHORT).show();
}
}
});
}
public void setSeekbarProgress(){
new Timer().scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
try {
if (mediaPlayer != null) {
seekBar.setProgress(mediaPlayer.getCurrentPosition());
}
}
catch (RuntimeException e){
Log.i("CRASH",""+e.getMessage());
}
}
},0,1000);
}
public void onSeekbarChange(){
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) {
}
});
}
}
这就是我想回到MediaPlayer活动（点击按钮）的地方：
mFloatingToolbar.setClickListener(new FloatingToolbar.ItemClickListener() {
@RequiresApi(api = Build.VERSION_CODES.M)
@Override
public void onItemClick(MenuItem item) {
switch (item.getItemId()) {
case R.id.music:
Intent intent = new Intent(getActivity(),MediaPlayerActivity.class);
startActivity(intent);
break;
case R.id.pause :
break;
case R.id.next :
Toast.makeText(getContext(), "Next", Toast.LENGTH_SHORT).show();
break;
default:
Toast.makeText(getContext(), "Back", Toast.LENGTH_SHORT).show();
verticalRecyclerViewAdapter.notifyDataSetChanged();
break;
}
}
@Override
public void onItemLongClick(MenuItem item) {
}
});