public class MainActivity extends AppCompatActivity implementsView.OnClickListener, SeekBar.OnSeekBarChangeListener, MediaPlayer.OnCompletionListener {private MediaPlayer mediaPlayer;//播放音频的

privateButton mPreviousBtn;privateButton mPlayBtn;privateButton mNextBtn;privateListView mListView;private Listlist;privateMyAdapter adapter;privateSeekBar mSeekBar;privateTextView mCurrentTimeTv;privateTextView mTotalTimeTv;//记录当前播放歌曲的位置

private intmCurrentPosition;private Handler mHandler=new Handler(newHandler.Callback() {

@Overridepublic booleanhandleMessage(Message message) {//展示给进度条和当前时间

int progress =mediaPlayer.getCurrentPosition();

mSeekBar.setProgress(progress);

mCurrentTimeTv.setText(parseTime(progress));//继续定时发送数据

updateProgress();return true;

}

});

@Overrideprotected voidonCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

mediaPlayer= newMediaPlayer();

mPreviousBtn=(Button) findViewById(R.id.mPreviousBtn);

mPlayBtn=(Button) findViewById(R.id.mPlayBtn);

mNextBtn=(Button) findViewById(R.id.mNextBtn);

mCurrentTimeTv=(TextView) findViewById(R.id.current_time_tv);

mTotalTimeTv=(TextView) findViewById(R.id.total_time_tv);

mSeekBar=(SeekBar) findViewById(R.id.seek_bar);

mSeekBar.setOnSeekBarChangeListener(this);

mPreviousBtn.setOnClickListener(this);

mPlayBtn.setOnClickListener(this);

mNextBtn.setOnClickListener(this);

initView();

}/*** 初始化view*/

private voidinitView() {

mListView=(ListView) findViewById(R.id.main_listview);

list= new ArrayList<>();//把扫描到的音乐赋值给list

list = MusicUtils.getMusicData(this);

adapter= new MyAdapter(this,list);

mListView.setAdapter(adapter);

mediaPlayer.setOnCompletionListener(this);

mListView.setOnItemClickListener(newAdapterView.OnItemClickListener() {

@Overridepublic void onItemClick(AdapterView> adapterView, View view, int i, longl) {//创建一个播放音频的方法，把点击到的地址传过去//list.get(i).path这个就是歌曲的地址//String path = list.get(i).path;//Log.i("WDD",path);

mCurrentPosition=i;

changeMusic(mCurrentPosition);//play(list.get(i).path);//String singer = list.get(i).singer;//歌手//String song = list.get(i).song;//歌曲名称//int duration = list.get(i).duration;//歌曲长度//String time = MusicUtils.formatTime(duration);//String s=singer+"\n"+song+"\n"+time;//AlertDialog.Builder builder=new AlertDialog.Builder(MainActivity.this);//builder.setTitle("歌曲");//builder.setMessage(s);//builder.show();

}

});

}///**//* 播放音频的方法//*///private void play(String path) {// //播放之前要先把音频文件重置//try {//mediaPlayer.reset();// //调用方法传进去要播放的音频路径//mediaPlayer.setDataSource(path);// //异步准备音频资源//mediaPlayer.prepareAsync();// //调用mediaPlayer的监听方法，音频准备完毕会响应此方法//mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {//@Override//public void onPrepared(MediaPlayer mediaPlayer) {//mediaPlayer.start();//开始音频//}//});//} catch (IOException e) {//e.printStackTrace();//}//}

@Overridepublic voidonClick(View view) {if (view.getId()==R.id.mPreviousBtn){//上一曲

changeMusic(--mCurrentPosition);

}else if (view.getId()==R.id.mPlayBtn){//暂停/播放//首次点击播放按钮，默认播放第0首

if (mediaPlayer==null){

changeMusic(0);

}else{if(mediaPlayer.isPlaying()){

mediaPlayer.pause();

}else{

mediaPlayer.start();

}

}

}else if (view.getId()==R.id.mNextBtn){//下一首

changeMusic(++mCurrentPosition);

}

}//基本数据类型和String在方法调用中传递的是值//其他数据类型在方法调用中传递的是引用//切歌

private void changeMusic(intposition){if (position<0){

mCurrentPosition= position =list.size()-1;

}else if (position>list.size()-1){

mCurrentPosition= position=0;

}if (mediaPlayer==null){

mediaPlayer=newMediaPlayer();

}try{//切歌之前先重置，释放掉之前的资源

mediaPlayer.reset();//设置播放源

mediaPlayer.setDataSource(list.get(position).path);//开始播放前的准备工作，加载多媒体资源，获取相关信息

mediaPlayer.prepare();//开始播放

mediaPlayer.start();

}catch(IOException e) {

e.printStackTrace();

}//切歌时重置进度条并展示歌曲时长

mSeekBar.setProgress(0);

mSeekBar.setMax(mediaPlayer.getDuration());

mTotalTimeTv.setText(parseTime(mediaPlayer.getDuration()));

updateProgress();

}private voidupdateProgress() {//使用Handler每间隔1s发送一次空消息，通知进度条更新

Message msg = Message.obtain();//获取一个现成的消息//使用MediaPlayer获取当前播放时间除以总时间的进度

int progress =mediaPlayer.getCurrentPosition();

msg.arg1=progress;

mHandler.sendMessageDelayed(msg, INTERNAL_TIME);

}private String parseTime(intoldTime) {

SimpleDateFormat sdf= new SimpleDateFormat("mm:ss");//时间格式

String newTime = sdf.format(newDate(oldTime));returnnewTime;

}private static final int INTERNAL_TIME = 1000;//音乐进度间隔时间

@Overridepublic void onProgressChanged(SeekBar seekBar, int i, booleanb) {

}

@Overridepublic voidonStartTrackingTouch(SeekBar seekBar) {

}//当手停止拖拽进度条时执行该方法//获取拖拽进度//将进度对应设置给MediaPlayer

@Overridepublic voidonStopTrackingTouch(SeekBar seekBar) {int progress =seekBar.getProgress();

mediaPlayer.seekTo(progress);

}

@Overridepublic voidonCompletion(MediaPlayer mediaPlayer) {

changeMusic(++mCurrentPosition);

}

}

**

* 音乐工具类,

*/

public class MusicUtils {

/**

* 扫描系统里面的音频文件，返回一个list集合

*/

public static List getMusicData(Context context) {

List list = new ArrayList();

// 媒体库查询语句(写一个工具类MusicUtils)

Cursor cursor = context.getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null,

null, MediaStore.Audio.AudioColumns.IS_MUSIC);

if (cursor != null) {

while (cursor.moveToNext()) {

Song song = new Song();

song.song = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));

song.singer = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));

song.path = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));

song.duration = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));

song.size = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));

if (song.size > 1000 * 800) {

// 注释部分是切割标题，分离出歌曲名和歌手 (本地媒体库读取的歌曲信息不规范)

if (song.song.contains("-")) {

String[] str = song.song.split("-");

song.singer = str[0];

song.song = str[1];

}

list.add(song);

}

}

// 释放资源

cursor.close();

}

return list;

}

/**

* 定义一个方法用来格式化获取到的时间

*/

public static String formatTime(int time) {

if (time / 1000 % 60 < 10) {

return time / 1000 / 60 + ":0" + time / 1000 % 60;

} else {

return time / 1000 / 60 + ":" + time / 1000 % 60;

}

}

}

package com.example.lenovo.yinyuekao2;

import android.content.Context;

import android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.TextView;

import java.util.List;

public class MyAdapter extends BaseAdapter {

private Context context;

private List list;

public MyAdapter(MainActivity mainActivity, List list) {

this.context = mainActivity;

this.list = list;

}

@Override

public int getCount() {

return list.size();

}

@Override

public Object getItem(int i) {

return list.get(i);

}

@Override

public long getItemId(int i) {

return i;

}

@Override

public View getView(final int i, View view, ViewGroup viewGroup) {

ViewHolder holder = null;

if (view == null) {

holder = new ViewHolder();

//引入布局

view = View.inflate(context, R.layout.item_music_listview, null);

//实例化对象

holder.song = (TextView) view.findViewById(R.id.item_mymusic_song);

holder.singer = (TextView) view.findViewById(R.id.item_mymusic_singer);

holder.duration = (TextView) view.findViewById(R.id.item_mymusic_duration);

holder.position = (TextView) view.findViewById(R.id.item_mymusic_postion);

view.setTag(holder);

} else {

holder = (ViewHolder) view.getTag();

}

//给控件赋值

holder.song.setText(list.get(i).song.toString());

holder.singer.setText(list.get(i).singer.toString());

//时间需要转换一下

int duration = list.get(i).duration;

String time = MusicUtils.formatTime(duration);

holder.duration.setText(time);

holder.position.setText(i+1+"");

return view;

}

class ViewHolder{

TextView song;//歌曲名

TextView singer;//歌手

TextView duration;//时长

TextView position;//序号

String parh;//地址

}

}

packagecom.example.lenovo.yinyuekao2;/*** Created by LENOVO on 2017/11/7.*/

/*** Created by user on 2016/6/24.

* 放置音乐*/

public classSong {/*** 歌手*/

publicString singer;/*** 歌曲名*/

publicString song;/*** 歌曲的地址*/

publicString path;/*** 歌曲长度*/

public intduration;/*** 歌曲的大小*/

public longsize;

}

xmlns:tools="http://schemas.android.com/tools"

android:id="@+id/activity_main"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context="com.example.lenovo.yinyuekao2.MainActivity">

android:orientation="horizontal"

android:id="@+id/main_textview"

android:layout_width="match_parent"

android:layout_height="40dp">

android:id="@+id/mPreviousBtn"

android:text="上一曲"

android:layout_width="0dp"

android:layout_weight="1"

android:layout_height="match_parent" />

android:id="@+id/mPlayBtn"

android:text="播放/暂停"

android:layout_width="0dp"

android:layout_weight="1"

android:layout_height="match_parent" />

android:id="@+id/mNextBtn"

android:text="下一曲"

android:layout_width="0dp"

android:layout_weight="1"

android:layout_height="match_parent" />

android:id="@+id/main_textview1"

android:layout_below="@+id/main_textview"

android:layout_width="match_parent"

android:layout_height="wrap_content">

android:id="@+id/current_time_tv"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="当前时间"/>

android:id="@+id/total_time_tv"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentRight="true"

android:text="全部时间"/>

android:id="@+id/seek_bar"

style="?android:progressBarStyleHorizontal"

android:layout_width="match_parent"

android:layout_height="50dp"

android:layout_toLeftOf="@id/total_time_tv"

android:layout_toRightOf="@id/current_time_tv"/>

android:id="@+id/main_listview"

android:layout_below="@+id/main_textview1"

android:layout_width="match_parent"

android:layout_height="match_parent"/>

android:layout_width="match_parent"

android:layout_height="110dp"

android:orientation="horizontal"

android:gravity="center_vertical"

android:padding="5dp">

android:id="@+id/item_mymusic_postion"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_margin="10dp"

android:text="1"

android:gravity="center"

android:textColor="#0d0c0c"

android:textSize="18sp" />

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_marginLeft="20dp"

>

android:id="@+id/item_mymusic_song"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="歌曲名"

android:textColor="#0d0c0c"

android:textSize="20dp" />

android:id="@+id/item_mymusic_singer"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_below="@+id/item_mymusic_song"

android:text="歌手"

android:textColor="#0d0c0c"

android:textSize="15sp" />

android:id="@+id/item_mymusic_duration"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_below="@+id/item_mymusic_song"

android:layout_marginLeft="15dp"

android:textColor="#0d0c0c"

android:layout_toRightOf="@+id/item_mymusic_singer"

android:text="时间"

android:textSize="15sp" />

记得加上权限