android音乐播放器开发 SweetMusicPlayer 实现思路

package com.huwei.sweetmusicplayer.datamanager;

 
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

 
import android.content.Context;
import android.content.Intent;
 
import android.provider.MediaStore;
 
import android.view.View;
import android.widget.BaseAdapter;
import android.widget.ListView;

import com.huwei.sweetmusicplayer.enums.MusicState;
import com.huwei.sweetmusicplayer.models.Song;
import com.huwei.sweetmusicplayer.ui.fragments.PlayingFragment;
 

 

public class MusicManager {
	private  int nowplaying_index=-1;
	public static boolean isPlaying=false;
	public static final String BOTTOMACTIONBAR_UPDATE="BOTTOMACTIONBAR_UPDATE";
	public static final String BOTTOMACTIONBAR_CHECKED="BOTTOMACTIONBAR_CHECKED";
	public static final String BOTTOMACTIONBAR_UNCHECKED="BOTTOMACTIONBAR_UNCHECKED";
	
	public static final String PLAY_BTN_CHECKED="PLAY_BTN_CHECKED";
	public static final String PLAY_BTN_UNCHECKED="PLAY_BTN_UNCHECKED";
	
	private static MusicManager instance;
	private Context context;
	private List<Song> songLists=new ArrayList<Song>();	//启动应用从数据库都进来时候的列表
	private ListView nowPlayingListView;		//正在播放音乐的列表控件
 
 
	
	
		/**
	 * 定义查找音乐信息数组。0.标题，1音乐时间,2.艺术家,3.音乐id，4.显示名字,5.全路径,6,专辑ID,7最后加入时间。
	 */
	public static  String[] media_info = new String[] { MediaStore.Audio.Media.TITLE,
			MediaStore.Audio.Media.DURATION, MediaStore.Audio.Media.ARTIST,
			MediaStore.Audio.Media._ID, MediaStore.Audio.Media.DISPLAY_NAME,
			MediaStore.Audio.Media.DATA, MediaStore.Audio.Media.ALBUM_ID ,MediaStore.MediaColumns.DATE_ADDED};
	
	

	
	public static MusicManager getInstance(){
		if(null==instance){
			instance=new MusicManager();
		}
		return instance;
	}
	
	//加入song到songLists
	public void addSong(Song song){
		songLists.add(song);
	}
	
 
	
	public void bind(Context context){
		this.context=context;
	}
	
	public void play(){
 
		
		Intent intent=new Intent();
		Song song=(Song) nowPlayingListView.getAdapter().getItem(nowplaying_index); 
		intent.setAction("com.huwei.sweetmusicplayer.services.LocalMusicService");
		intent.putExtra("song", song);
		intent.putExtra("op", MusicState.PLAYING.ordinal());	//播放选项
		context.startService(intent);
		
 
		
		//通知playButton
		Intent intent3=new Intent(PLAY_BTN_CHECKED);
		context.sendBroadcast(intent3);
		
		
		isPlaying=true;
	}
	
	//先停止，再播放
	public void restartPlay(){
		stopUnNotifyView();
		play();
	}
	
	public void previousSong(){
		setNowplaying_index(nowplaying_index-1);
 		restartPlay();
	}
	
	public void nextSong(){
		//都要用set方法。便于通知更新视图
		setNowplaying_index(nowplaying_index+1);
 		restartPlay();
	}
	
	//随机播放一首歌
	public void random_a_song(){
		getRandom_song();
		restartPlay();
	}
	
	public void pause(){
		Intent intent=new Intent();
		intent.setAction("com.huwei.sweetmusicplayer.services.LocalMusicService");
		intent.putExtra("op", MusicState.PAUSE.ordinal());	//播放选项
		context.startService(intent);
		
 
		
		isPlaying=false;
		
		//通知playButton
		Intent intent3=new Intent(PLAY_BTN_UNCHECKED);
		context.sendBroadcast(intent3);
	}
	
	
	//发送停止音乐广播，可是不更新视图
	public void stopUnNotifyView(){
		Intent intent=new Intent();
		intent.setAction("com.huwei.sweetmusicplayer.services.LocalMusicService");
		intent.putExtra("op", MusicState.STOP.ordinal());	//播放选项
		context.startService(intent);
	}
	
	
	//停止音乐
	public void stop(){
		stopUnNotifyView();
		
 
	}
	
	
	//设置音乐进度
	public void setProgress(int progress){
	 
		Intent intent=new Intent("com.huwei.sweetmusicplayer.services.LocalMusicService");
		intent.putExtra("progress", progress);
		intent.putExtra("op", MusicState.PROGRESS_CHANGE.ordinal());
		context.startService(intent);
	}
	
	//随机得到一首歌
	public int getRandom_song(){
		int random=new Random().nextInt(nowPlayingListView.getAdapter().getCount());
		setNowplaying_index(random);
		return nowplaying_index ;
	}

	public List<Song> getSongLists() {
		return songLists;
	}


	public int getNowplaying_index() {
		return nowplaying_index;
	}

	public void setNowplaying_index(int i) {
		int count=nowPlayingListView.getCount();
		nowplaying_index=(i+count)%count;
	 
	 
		
		//通知ListView控件刷新
		 BaseAdapter adapter=(BaseAdapter) nowPlayingListView.getAdapter();
		 adapter.notifyDataSetChanged();
 
		 
		 //通知bottomActionBar更新
		 Intent intent=new Intent(BOTTOMACTIONBAR_UPDATE);
		 context.sendBroadcast(intent);
		 
		 //通知PlaySong界面更新
		 Intent intent2=new Intent(PlayingFragment.PLAYSONG_UPDATE);
		 context.sendBroadcast(intent2);
	}

	public ListView getNowPlayingListView() {
		return nowPlayingListView;
	}

	public void setNowPlayingListView(ListView nowPlayingListView) {
		
		this.nowPlayingListView = nowPlayingListView;
	
	}

	public Song getNowPlayingSong(){
		return (Song) nowPlayingListView.getAdapter().getItem(nowplaying_index);
	}
	
	
	//歌词界面操作状态
	public  static  class OperateState{
		public static String READLRC_SUCCESS="READLRC_SUCCESS";
		public static String READLRC_LISTNULL="READLRC_LISTNULL";
		public static String READLRC_ONLINE="READLRC_ONLINE";
		public static String READLRCFILE_FAIL="READLRCFILE_FAIL";
		public static String READLRCONLINE_FAIL="READLRCONLINE_FAIL";
	}
		
	public Song getSongByIndex(int index){
		return (Song) nowPlayingListView.getAdapter().getItem(index);
	}
}