/**     * 获取默认专辑图片     */    public static Bitmap getDefaultArtwork(Context context,boolean small) {        BitmapFactory.Options opts = new BitmapFactory.Options();        opts.inPreferredConfig = Bitmap.Config.RGB_565;        if(small){//返回小图片            return BitmapFactory.decodeStream(context.getResources().openRawResource(R.mipmap.music), null, opts);        }        return BitmapFactory.decodeStream(context.getResources().openRawResource(R.mipmap.music), null, opts);    }    /**     * 从文件当中获取专辑封面位图     */    private static Bitmap getArtworkFromFile(Context context, long songid, long albumid){        Bitmap bm = null;        if(albumid < 0 && songid < 0) {            throw new IllegalArgumentException("Must specify an album or a song id");        }        try {            BitmapFactory.Options options = new BitmapFactory.Options();            FileDescriptor fd = null;            if(albumid < 0){                Uri uri = Uri.parse("content://media/external/audio/media/"                        + songid + "/albumart");                ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(uri, "r");                if(pfd != null) {                    fd = pfd.getFileDescriptor();                }            } else {                Uri uri = ContentUris.withAppendedId(albumArtUri, albumid);                ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(uri, "r");                if(pfd != null) {                    fd = pfd.getFileDescriptor();                }            }            options.inSampleSize = 1;            // 只进行大小判断            options.inJustDecodeBounds = true;            // 调用此方法得到options得到图片大小            BitmapFactory.decodeFileDescriptor(fd, null, options);            // 我们的目标是在800pixel的画面上显示            // 所以需要调用computeSampleSize得到图片缩放的比例            options.inSampleSize = 100;            // 我们得到了缩放的比例，现在开始正式读入Bitmap数据            options.inJustDecodeBounds = false;            options.inDither = false;            options.inPreferredConfig = Bitmap.Config.ARGB_8888;            //根据options参数，减少所需要的内存            bm = BitmapFactory.decodeFileDescriptor(fd, null, options);        } catch (FileNotFoundException e) {            e.printStackTrace();        }        return bm;    }    /**     * 获取专辑封面位图对象     */    public static Bitmap getArtwork(Context context, long song_id, long album_id, boolean allowdefalut, boolean small){        if(album_id < 0) {            if(song_id < 0) {                Bitmap bm = getArtworkFromFile(context, song_id, -1);                if(bm != null) {                    return bm;                }            }            if(allowdefalut) {                return getDefaultArtwork(context, small);            }            return null;        }        ContentResolver res = context.getContentResolver();        Uri uri = ContentUris.withAppendedId(albumArtUri, album_id);        if(uri != null) {            InputStream in = null;            try {                in = res.openInputStream(uri);                BitmapFactory.Options options = new BitmapFactory.Options();                //先制定原始大小                options.inSampleSize = 1;                //只进行大小判断                options.inJustDecodeBounds = true;                //调用此方法得到options得到图片的大小                BitmapFactory.decodeStream(in, null, options);                /** 我们的目标是在你N pixel的画面上显示。 所以需要调用computeSampleSize得到图片缩放的比例 **/                /** 这里的target为800是根据默认专辑图片大小决定的，800只是测试数字但是试验后发现完美的结合 **/                if(small){                    options.inSampleSize = computeSampleSize(options, 40);                } else{                    options.inSampleSize = computeSampleSize(options, 600);                }                // 我们得到了缩放比例，现在开始正式读入Bitmap数据                options.inJustDecodeBounds = false;                options.inDither = false;                options.inPreferredConfig = Bitmap.Config.ARGB_8888;                in = res.openInputStream(uri);                return BitmapFactory.decodeStream(in, null, options);            } catch (FileNotFoundException e) {                Bitmap bm = getArtworkFromFile(context, song_id, album_id);                if(bm != null) {                    if(bm.getConfig() == null) {                        bm = bm.copy(Bitmap.Config.RGB_565, false);                        if(bm == null && allowdefalut) {                            return getDefaultArtwork(context, small);                        }                    }                } else if(allowdefalut) {                    bm = getDefaultArtwork(context, small);                }                return bm;            } finally {                try {                    if(in != null) {                        in.close();                    }                } catch (IOException e) {                    e.printStackTrace();                }            }        }        return null;    }    /**     * 对图片进行合适的缩放     */    public static int computeSampleSize(Options options, int target) {        int w = options.outWidth;        int h = options.outHeight;        int candidateW = w / target;        int candidateH = h / target;        int candidate = Math.max(candidateW, candidateH);        if(candidate == 0) {            return 1;        }        if(candidate > 1) {            if((w > target) && (w / candidate) < target) {                candidate -= 1;            }        }        if(candidate > 1) {            if((h > target) && (h / candidate) < target) {                candidate -= 1;            }        }        return candidate;    }

    //回调播放状态下的UI设置    public void changeUIStatusOnPlay(int position){//更新UI状态--当前播放的音乐,传进来当前音乐的下标        if (position>=0 && position

package com.iwanghang.drmplayer.adapter;import android.content.Context;import android.graphics.Bitmap;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.TextView;import com.iwanghang.drmplayer.MyMusicListFragment;import com.iwanghang.drmplayer.R;import com.iwanghang.drmplayer.utils.MediaUtils;import com.iwanghang.drmplayer.vo.Mp3Info;import java.util.ArrayList;/** * 自定义的音乐列表适配器 * 为了方便扩展，因为之前没有考虑到显示专辑封面 * Created by iwanghang on 16/4/16. */public class MyMusicListAdapter extends BaseAdapter{    private Context ctx; //上下文对象引用    private ArrayList mp3Infos;//存放Mp3Info引用的集合    private Mp3Info mp3Info;//Mp3Info对象引用    private int pos = -1;//列表位置    /**     * 构造函数     * @param ctx上下文     * @param mp3Infos  集合对象     */    public MyMusicListAdapter(Context ctx, ArrayList mp3Infos){        this.ctx = ctx;        this.mp3Infos = mp3Infos;        System.out.println("MyMusicListAdapter.java #0 : ctx = " + ctx + ",mp3Infos = " + mp3Infos.size());    }    public ArrayList getMp3Infos() {        System.out.println("MyMusicListAdapter.java #1 : public ArrayList getMp3Infos() {");        return mp3Infos;    }    public void setMp3Infos(ArrayList mp3Infos) {        System.out.println("MyMusicListAdapter.java #2 : public void setMp3Infos(ArrayList mp3Infos) {");        this.mp3Infos = mp3Infos;    }    @Override    public int getCount() {        //System.out.println("MyMusicListAdapter.java #3 : public int getCount() {" + mp3Infos.size());        //return mp3Infos.size();        return mp3Infos.size();    }    @Override    public Object getItem(int position) {        System.out.println("MyMusicListAdapter.java #4 : public Object getItem(int position) {");        return mp3Infos.get(position);    }    @Override    public long getItemId(int position) {        //System.out.println("MyMusicListAdapter.java #5 : public long getItemId(int position) {");        return position;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        //System.out.println("MyMusicListAdapter.java #6 : public View getView ");        ViewHolder vh;        if(convertView==null){            //vh = new ViewHolder();            convertView = LayoutInflater.from(ctx).inflate(R.layout.item_music_list,null);            vh = new ViewHolder();            vh.textView1_title = (TextView) convertView.findViewById(R.id.textView1_title);            vh.textView2_singer = (TextView) convertView.findViewById(R.id.textView2_singer);            vh.textView3_time = (TextView) convertView.findViewById(R.id.textView3_time);            vh.imageView1_ablum = (ImageView) convertView.findViewById(R.id.imageView1_ablum);            //System.out.println("MyMusicListAdapter.java #7 : textView1_title = " + vh.textView1_title);            convertView.setTag(vh);//表示给View添加一个格外的数据，        }else {            vh = (ViewHolder)convertView.getTag();//通过getTag的方法将数据取出来        }        Mp3Info mp3Info = mp3Infos.get(position);        vh.textView1_title.setText(mp3Info.getTitle());//显示标题        vh.textView2_singer.setText(mp3Info.getArtist());//显示歌手        vh.textView3_time.setText(MediaUtils.formatTime(mp3Info.getDuration()));//显示时长        //获取专辑封面图片        Bitmap albumBitmapItem = MediaUtils.getArtwork(ctx,mp3Info.getId(),mp3Info.getAlbumId(),true,true);        System.out.println("MyMusicListAdapter.java #8 : albumBitmapItem = " + albumBitmapItem.getConfig());        //改变播放界面专辑封面图片        vh.imageView1_ablum.setImageBitmap(albumBitmapItem);        //vh.imageView1_ablum.setImageResource(R.mipmap.music);        return convertView;    }    /**     * 定义一个内部类     * 声明相应的控件引用     */    static class ViewHolder{        //所有控件对象引用        TextView textView1_title;//标题        TextView textView2_singer;//歌手        TextView textView3_time;//时长        ImageView imageView1_ablum;//专辑封面图片    }}//inflate(R.layout.item_music_list,null);