团队博客14

实现异步任务机制---AsyncTask

  AsyncTask直接继承与object类:

import android.os.AsyncTask;

  实现异步加载音频的一段代码:

//异步加载音频
	public class MyVideo extends AsyncTask<String, Integer, ArrayList<MusicInfor>> {

        @Override
        protected ArrayList<MusicInfor> doInBackground(String... params) {
        	ArrayList<MusicInfor> lpath=new ArrayList<MusicInfor>();
            Uri mVideoUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
            ContentResolver mContentResolver =context.getContentResolver();
			Cursor cursor=mContentResolver.query(mVideoUri, null, null, null,null);
			while(cursor.moveToNext())
			{
				MusicInfor music=new MusicInfor();
				
				//音乐ID
				int id=cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media._ID));
				//音乐名称
				String name=cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));
				//音乐存储路径
				String path=cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
				//音乐修改日期
				long updateTime=cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATE_MODIFIED));
		 	    updateTime = updateTime*1000;
				//格式化时间,获取年,月,日
				String[] times =  common.getTimeInfo(updateTime);
				String date=times[0]+"年"+times[1]+"月"+times[2]+"日    "+times[3]+":"+times[4]+":"+times[5];
				//获取音频长度
				long ltime=cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));
				String mtime=common.GetTime(ltime);
				//获取音频大小
				int lsize=cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));
				
				BigDecimal pSize=common.parseApkSize(lsize);
		        long size=pSize.longValue();
				music=new MusicInfor(name,path,date,size,mtime);
				lpath.add(music);
				
			}
			cursor.close();
			return lpath;
        }
    	

  

在这段代码中,我们重写了doInBackground(String... params)这个方法,这个方法在后台线程中执行,完成异步任务的主要工作,通常需要较长的时间。

posted @ 2016-09-14 10:48  JYJe族  阅读(111)  评论(0编辑  收藏  举报