package auggie.gallery;import android.content.ContentResolver;import android.content.Context;import android.database.Cursor;import android.provider.MediaStore;import android.support.v4.content.AsyncTaskLoader;import android.util.SparseArray;import java.util.ArrayList;import java.util.List;/** * Created With Android Studio * User @47 * Date 2014-08-25 * Time 10:29 * 加载 相册的图片 */public class GalleryImageLoader extends AsyncTaskLoader<List<OImageBean>> {    /** 需要查询的列**/    public static final String[] QUERY_COLUMN_THUMBS = {            MediaStore.Images.Thumbnails._ID,            MediaStore.Images.Thumbnails.DATA,//图片在内存卡地址            MediaStore.Images.Thumbnails.IMAGE_ID    };    /** 需要查询的列**/    public static final String[] QUERY_COLUMN_ORIGINAL = {            MediaStore.Images.ImageColumns._ID,            MediaStore.Images.ImageColumns.DATA,//图片在内存卡地址            MediaStore.Images.ImageColumns.SIZE,//图片大小            MediaStore.Images.ImageColumns.DISPLAY_NAME,//显示的名字            MediaStore.Images.ImageColumns.DATE_MODIFIED,//修改日期            MediaStore.Images.ImageColumns.BUCKET_ID,//文件夹ID            MediaStore.Images.ImageColumns.BUCKET_DISPLAY_NAME//文件夹名字    };    private List<OImageBean> mImageList;    private List<BucketBean> mBucketList;    private SparseArray<BucketBean> mBucketArray;    public List<BucketBean> getBucketList() {        if(mBucketList == null){            mBucketList = new ArrayList<BucketBean>();            int size = mBucketArray.size();            for(int i = 0 ; i < size ; i++){                mBucketList.add(mBucketArray.get(mBucketArray.keyAt(i)));            }        }        return mBucketList;    }    public GalleryImageLoader(Context context) {        super(context);    }    @Override    public List<OImageBean> loadInBackground() {        mBucketList = null;//清理        mImageList = new ArrayList<OImageBean>();        ContentResolver contentResolver = getContext().getContentResolver();        SparseArray<OImageBean> indexById  = new SparseArray<OImageBean>();        Cursor cursor = contentResolver.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,                QUERY_COLUMN_ORIGINAL,                null,null,MediaStore.Images.Media.DATE_MODIFIED+" DESC");        if(!cursor.moveToFirst()) return mImageList;        mBucketArray = new SparseArray<BucketBean>();        do {            OImageBean bean = new OImageBean(cursor);            mImageList.add(bean);            indexById.append(bean.id, bean);            //添加文件夹列表中            BucketBean bucketBean =                    mBucketArray.get(                            bean.bucketID,                            new BucketBean(bean.bucketID,bean.bucketDisplayName));            mBucketArray.append(bucketBean.buckID,bucketBean);            bucketBean.oImageBeanList.add(bean);        } while (cursor.moveToNext());        cursor.close();        //查询缩略图d        cursor = contentResolver.query(                MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI,                QUERY_COLUMN_THUMBS,null,null,                MediaStore.Images.Thumbnails.IMAGE_ID + " DESC");        //获取缩略图        if(cursor.moveToFirst()){            do{                int imageId = cursor.getInt(cursor.getColumnIndex(MediaStore.Images.Thumbnails                        .IMAGE_ID));                OImageBean bean  =  indexById.get(imageId);                if(bean == null) {                    continue;                }                bean.setThumb(cursor);            }while (cursor.moveToNext());        }        cursor.close();        return mImageList;    }    @Override    protected void onReset() {        super.onReset();        //要重置的时候，停止加载        onStopLoading();        if(mImageList != null){//释放之前的资源            onReleaseResource(mImageList);            mImageList = null;        }    }    @Override    protected void onStopLoading() {        super.onStopLoading();        cancelLoad();    }    @Override    public void onCanceled(List<OImageBean> data) {        super.onCanceled(data);        onReleaseResource(data);    }    @Override    public void deliverResult(List<OImageBean> data) {        if(isReset()){//如果已经关闭了，我们不需要结果            if(data != null) onReleaseResource(data);        }        List<OImageBean> oldList = mImageList;        mImageList = data;        //如果是刚开始，我们立刻传递结果给人家        if(isStarted()){            super.deliverResult(data);        }        if(oldList != null){            onReleaseResource(oldList);        }    }    @Override    protected void onStartLoading() {        //如果mImageList 不是空，就立刻发放数据        if(mImageList != null) deliverResult(mImageList);        //如果数据有改变过，立刻加载数据        if(takeContentChanged() || mImageList == null){            forceLoad();        }    }    private void onReleaseResource(List<OImageBean> mList) {        //如果是cursor 这里需要释放资源    }}