【发布时间】：2021-04-04 02:56:11
【问题描述】：
我尝试了一种方法来播放下一首歌曲，但效果很好，但我认为这不是正确的方式，所以如果您有任何建议，我该如何更正，请告诉我，拜托。
Java 代码
public class Musicplay extends AppCompatActivity implements View.OnClickListener {
Button play,next,previous;
TextView song mar;
SeekBar seekBar;
MediaPlayer mediaPlayer;
int position,idr;
Handler handler=new Handler();
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.playdisplay);
Intent i=getIntent();
position=i.getIntExtra("position",0);
play=findViewById(R.id.pause);
next=findViewById(R.id.next);
previous=findViewById(R.id.previous);
songmar=findViewById(R.id.songnamemar);
songmar.setSelected(true);
songmar.setText(Musiclist.songname.get(position));
seekBar=findViewById(R.id.seekBar);
if(mediaPlayer!=null)
{
mediaPlayer.stop();
mediaPlayer.release();
}
Uri uri=Uri.parse(String.valueOf(new File(Musiclist.songpath.get(position))));
mediaPlayer=MediaPlayer.create(Musicplay.this,uri);
seekBar.setMax(mediaPlayer.getDuration());
mediaPlayer.start();
play.setBackgroundResource(R.drawable.ic_pause);
Thread thread=new Thread(){
@Override
public void run() {
super.run();
int max=mediaPlayer.getDuration();
int currentposition=0;
while (currentposition<max)
{
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
currentposition=mediaPlayer.getCurrentPosition();
seekBar.setProgress(currentposition);
}
}
};
thread.start();
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
mediaPlayer.seekTo(seekBar.getProgress());
}
});
next.setOnClickListener(Musicplay.this);
play.setOnClickListener(Musicplay.this);
previous.setOnClickListener(Musicplay.this);
mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
mediaPlayer.stop();
mediaPlayer.release();
if(position<(Musiclist.songname.size()-1)){
position=position +1;
}
else
{
position=0;
}
Intent intent=new Intent(Musicplay.this,Musicplay.class);
intent.putExtra("position",position);
startActivity(intent);
}
});
}
@Override
public void onClick(View v) {
idr=v.getId();
Thread thread2=new Thread(){
@Override
public void run() {
super.run();
handler.post(new Runnable() {
@Override
public void run() {
switch (idr){
case R.id.pause:
if(mediaPlayer.isPlaying()){
mediaPlayer.pause();
play.setBackgroundResource(R.drawable.ic_play);
}
else {
play.setBackgroundResource(R.drawable.ic_pause);
mediaPlayer.start();
}
break;
case R.id.next:
mediaPlayer.stop();
mediaPlayer.release();
if(position<(Musiclist.songname.size()-1)){
position=position +1;
Uri uri=Uri.parse(String.valueOf(new File(Musiclist.songpath.get(position))));
mediaPlayer=MediaPlayer.create(Musicplay.this,uri);
int a=0;
for(int i=0;i<150;i++)
{
a=a+1;
}
mediaPlayer.start();
play.setBackgroundResource(R.drawable.ic_pause);
songmar.setText(Musiclist.songname.get(position));
songmar.setSelected(true);
}
else {
position=0;
Uri uri=Uri.parse(String.valueOf(new File(Musiclist.songpath.get(position))));
mediaPlayer=MediaPlayer.create(Musicplay.this,uri);
int a=0;
for(int i=0;i<150;i++)
{
a=a+1;
}
mediaPlayer.start();
play.setBackgroundResource(R.drawable.ic_pause);
songmar.setText(Musiclist.songname.get(position));
songmar.setSelected(true);
}
break;
case R.id.previous:
mediaPlayer.stop();
mediaPlayer.release();
if(position>0){
position=position-1;
Uri uri=Uri.parse(String.valueOf(new File(Musiclist.songpath.get(position))));
mediaPlayer=MediaPlayer.create(Musicplay.this,uri);
int a=0;
for(int i=0;i<150;i++)
{
a=a+1;
}
mediaPlayer.start();
play.setBackgroundResource(R.drawable.ic_pause);
songmar.setText(Musiclist.songname.get(position));
songmar.setSelected(true);
}
else {
position=Musiclist.songname.size()-1;
Uri uri=Uri.parse(String.valueOf(new File(Musiclist.songpath.get(position))));
mediaPlayer=MediaPlayer.create(Musicplay.this,uri);
int a=0;
for(int i=0;i<150;i++)
{
a=a+1;
}
mediaPlayer.start();
play.setBackgroundResource(R.drawable.ic_pause);
songmar.setText(Musiclist.songname.get(position));
songmar.setSelected(true);
}
break;
}
}
});
}
};
thread2.start();
}
}
请建议最好的方式，而不是开始相同的活动，我该如何播放下一首歌曲。我什至也尝试在 Oncompletelistner 中更改歌曲，但它只工作一次，然后就不会改变。
【问题讨论】：
标签： android performance optimization