Android 音乐播放器（暂停、下一首、上一首）

1.编写主页面，使用listview组件放置音乐列表信息

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"tools:context=".MainActivity"android:orientation="vertical"android:background="#D8D8D8"><ScrollViewandroid:layout_width="match_parent"android:layout_height="match_parent"android:layout_above="@id/local" ><LinearLayoutandroid:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><com.example.myapplication.MyListVIewandroid:id="@+id/video_list"android:layout_width="match_parent"android:layout_height="wrap_content"/></LinearLayout></ScrollView><RelativeLayoutandroid:layout_width="match_parent"android:layout_height="70dp"android:id="@+id/local"android:background="#ECC8C8"android:layout_alignParentBottom="true"><ImageViewandroid:id="@+id/img"android:layout_width="40dp"android:layout_height="40dp"android:src="@drawable/bold"android:layout_marginLeft="10dp"android:layout_centerVertical="true"/><TextViewandroid:id="@+id/song"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="告白气球"android:layout_toRightOf="@id/img"android:layout_marginTop="20dp"android:layout_marginLeft="20dp"android:textColor="#000"android:textSize="15sp"/><TextViewandroid:id="@+id/name"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="周杰伦"android:layout_toRightOf="@id/img"android:layout_marginTop="40dp"android:layout_marginLeft="20dp"android:textColor="#000"android:textSize="12sp"/><TextViewandroid:id="@+id/time"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="3:30"android:layout_centerVertical="true"android:layout_centerHorizontal="true"android:textColor="#000"android:textSize="12sp"/><TextViewandroid:id="@+id/next"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="下一曲"android:textSize="12sp"android:textColor="#000"android:layout_alignParentRight="true"android:layout_centerVertical="true"android:layout_marginRight="10dp"/><TextViewandroid:id="@+id/stop"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="暂停"android:textSize="12sp"android:textColor="#000"android:layout_toLeftOf="@id/next"android:layout_centerVertical="true"android:enabled="false"android:layout_marginRight="20dp"/><TextViewandroid:id="@+id/up"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="上一曲"android:textSize="12sp"android:textColor="#000"android:layout_toLeftOf="@id/stop"android:layout_centerVertical="true"android:layout_marginRight="20dp"/></RelativeLayout></RelativeLayout>

2.写Bean类、Adapter适配器

package com.example.myapplication;import java.io.Serializable;public class VideoBean implements Serializable {private int id;private String song;private String singer;private String album;private String time;private int path;public VideoBean(int id, String song, String singer, String album, String time, int path) {this.id = id;this.song = song;this.singer = singer;this.album = album;this.time = time;this.path = path;}public String getTime() {return time;}public String getAlbum() {return album;}public int getId() {return id;}public int getPath() {return path;}public String getSinger() {return singer;}public String getSong() {return song;}
}

package com.example.myapplication;import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;import java.util.List;public class VideoAdapter extends BaseAdapter {private List<VideoBean> list;private Context context;public VideoAdapter(List<VideoBean> list, Context context) {this.list = list;this.context = context;}@Overridepublic int getCount() {return list.size();}@Overridepublic Object getItem(int position) {return position;}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {if (convertView==null){convertView= LayoutInflater.from(context).inflate(R.layout.adaper_video,parent,false);}VideoBean bean=list.get(position);TextView id=convertView.findViewById(R.id.id);TextView song=convertView.findViewById(R.id.song);TextView singer=convertView.findViewById(R.id.singer);TextView album=convertView.findViewById(R.id.album);TextView time=convertView.findViewById(R.id.time);id.setText(bean.getId()+"");song.setText(bean.getSong());singer.setText(bean.getSinger());album.setText(bean.getAlbum());time.setText(bean.getTime());return convertView;}
}

3.写listview的子布局页面

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><RelativeLayoutandroid:layout_width="match_parent"android:layout_height="100dp"android:background="@drawable/shape10"android:orientation="horizontal"android:paddingLeft="30dp"android:paddingRight="30dp"><TextViewandroid:id="@+id/id"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="1"android:textSize="35sp"android:textColor="#000"android:layout_centerVertical="true"/><LinearLayoutandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:orientation="vertical"android:layout_centerVertical="true"android:layout_marginLeft="50dp"><TextViewandroid:id="@+id/song"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="告白气球"android:textSize="25sp"android:textColor="#000"android:layout_gravity="center"/><LinearLayoutandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:orientation="horizontal"android:layout_marginTop="10dp"><TextViewandroid:id="@+id/singer"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="许嵩"android:textSize="20sp"android:textColor="#000"android:layout_gravity="center"/><TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="|"android:textSize="20sp"android:textColor="#000"android:layout_marginLeft="10dp"android:layout_gravity="center"/><TextViewandroid:id="@+id/album"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="专辑名称"android:textSize="20sp"android:textColor="#000"android:layout_marginLeft="10dp"android:layout_gravity="center"/></LinearLayout></LinearLayout><TextViewandroid:id="@+id/time"android:layout_width="wrap_content"android:layout_height="wrap_content"android:textSize="18sp"android:layout_alignParentRight="true"android:text="4:20"android:textColor="#000"android:layout_alignParentBottom="true"android:layout_marginBottom="15dp"/></RelativeLayout></LinearLayout>

下载几个mp3音乐导入raw中

4.编写主页面java文件

package com.example.myapplication;import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;import android.content.Intent;
import android.media.MediaParser;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;import java.io.IOException;
import java.util.ArrayList;
import java.util.List;public class MainActivity extends AppCompatActivity {private TextView song,name,next,stop,up,time;private ListView video_list;private List<VideoBean> data;private MediaPlayer mediaPlayer;private int num=0;private int id=0;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);init();data=new ArrayList<>();data.add(new VideoBean(1,"七月上","Jam","七月上","3:10",R.raw.a1));data.add(new VideoBean(2,"大摇大摆迎春来","大张伟","七月上","2:54",R.raw.a2));data.add(new VideoBean(3,"抱歉","科德夏萍","陈慧琳","3:56",R.raw.a3));data.add(new VideoBean(4,"白色恋人","游鸿铭","游鸿铭","4:48",R.raw.a4));data.add(new VideoBean(4,"白色恋人","游鸿铭","游鸿铭","4:48",R.raw.a4));data.add(new VideoBean(4,"白色恋人","游鸿铭","游鸿铭","4:48",R.raw.a4));video_list.setAdapter(new VideoAdapter(data,MainActivity.this));video_list.setOnItemClickListener(new AdapterView.OnItemClickListener() {@Overridepublic void onItemClick(AdapterView<?> parent, View view, int position, long id) {VideoBean bean=data.get(position);song.setText(bean.getSong());name.setText(bean.getSinger());time.setText(bean.getTime());if (mediaPlayer != null) {if (mediaPlayer.isPlaying()) {mediaPlayer.stop();}mediaPlayer.release();mediaPlayer = null;}mediaPlayer=MediaPlayer.create(MainActivity.this,bean.getPath());mediaPlayer.start();stop.setEnabled(true);}});stop.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {num++;if (num%2==1){mediaPlayer.pause();stop.setText("开始");}else if (num%2==0){stop.setText("暂停");mediaPlayer.start();}}});next.setOnClickListener(new View.OnClickListener() {public void onClick(View v) {mediaPlayer.reset();id = (id % data.size()) + 1;if (id >= data.size()) {id = 0;}VideoBean bean = data.get(id);song.setText(bean.getSong());name.setText(bean.getSinger());time.setText(bean.getTime());mediaPlayer = MediaPlayer.create(MainActivity.this, bean.getPath());mediaPlayer.start();// 恢复“暂停”按钮的文本，因为我们现在正在播放新的歌曲stop.setText("暂停");stop.setEnabled(true);}});up.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {mediaPlayer.reset();id = id-1;// 如果索引超出了列表大小，将其重置为0（列表的第一首歌曲）if (id <0) {id = data.size() - 1;}VideoBean bean = data.get(id);song.setText(bean.getSong());name.setText(bean.getSinger());time.setText(bean.getTime());mediaPlayer = MediaPlayer.create(MainActivity.this, bean.getPath());mediaPlayer.start();// 恢复“暂停”按钮的文本，因为我们现在正在播放新的歌曲stop.setText("暂停");stop.setEnabled(true);}});}private void init(){song=findViewById(R.id.song);name=findViewById(R.id.name);next=findViewById(R.id.next);stop=findViewById(R.id.stop);up=findViewById(R.id.up);time=findViewById(R.id.time);video_list=findViewById(R.id.video_list);}}