在Android中，对于多媒体文件，系统提供了媒体扫描（MediaScanner）服务，在扫描到相应的文件后，该文件的信息会被存到特定的数据库中。对于图像文件，也是如此。对于SD卡，其URI地址为android. provider.MediaStore.Images. Media. EXTERNAL_CONTENT_URI，对于终端空间，其URI地址为android. provider.MediaStore.Images. Media. INTERNAL_CONTENT_URI。数据库包含的字段包括：DATA、SIZE、DISPLAY_NAME、TITLE、DATE_ADDED、DATE_MODIFIED、MIME_TYPE等。

package com.miaozl.test;

在UI层面，多个图像的浏览通常是通过Gallery来实现的，下面是利用Gallery进行图像浏览的一个实例：

import android.app.Activity;
    import android.content.Context;
    import android.os.Bundle;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.Gallery;
    import android.widget.ImageView;
    public class GalleryActivity extends Activity {
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            Gallery g = (Gallery) findViewById(R.id.gallery);
            g.setAdapter(new GalleryAdapter(this));
        }
        private class GalleryAdapter extends BaseAdapter {
            private Context mContext;
            private Integer[] mImageIds = {
                R.drawable.photo1,
                R.drawable.photo2,
                R.drawable.photo3,
                R.drawable.photo4,
                R.drawable.photo5,
                R.drawable.photo6,
            };
        public GalleryAdapter(Context c) {
                mContext = c;
            }
        public int getCount() {
            return mImageIds.length;
        }
        public Object getItem(int position) {
            return position;
        }
        public long getItemId(int position) {
            return position;
        }
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView i = new ImageView(mContext);
            i.setImageResource(mImageIds[position]);
            return i;
            }
        }
    }

下图是图像浏览的效果图。

如果加载的是数据库中的图片，基于的适配器的基类为CursorAdapter。