移动开发----ContentProvider之通过ContentResolver获取图像、视频、音频举例

MediaStore中定义了一系列的数据表格，通过ContentResolver提供的查询接口，我们可以得到各种需要的媒体信息。通过以下两个URI可以扫描设备外部和内部的媒体文件。Android系统提供了MediaProvider，MediaStore，MediaScanner接口，通过Content Provider的方式提供给用户。以下是一个简单的例子：（注意，项目使用AndroidAnnotation框架）

 package com.example.testaa;

 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;

 import org.androidannotations.annotations.AfterViews;
 import org.androidannotations.annotations.Click;
 import org.androidannotations.annotations.EActivity;
 import org.androidannotations.annotations.ViewById;

 import android.app.Activity;
 import android.database.Cursor;
 import android.net.Uri;
 import android.provider.MediaStore;
 import android.widget.Button;
 import android.widget.TextView;
 /*
  *@author: ZhengHaibo
  *web:     http://blog.csdn.net/nuptboyzhb
  *mail:    [email protected]
  *2014-4-15  Nanjing,njupt,China
  */
 @EActivity(R.layout.activity_main)
 public class MainActivity extends Activity {

     @ViewById
     Button getImage;

     @ViewById
     Button getVideo;

     @ViewById
     Button getAudio;

     @ViewById
     TextView myTextView;

     /**
      * 加载完View之后进行的处理
      */
     @AfterViews
     void afterViewProcess() {

     }

     /**
      * 获取图像列表
      */
     @Click
     void getImage() {
         String[] projection = { MediaStore.Images.Media._ID,
                 MediaStore.Images.Media.DISPLAY_NAME,
                 MediaStore.Images.Media.DATA };
         String orderBy = MediaStore.Images.Media.DISPLAY_NAME;
         Uri uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
         getContentProvider(uri,projection, orderBy);
     }

     /**
      * 获取视频列表
      */
     @Click
     void getVideo() {
         // TODO Auto-generated method stub
          String []projection = { MediaStore.Video.Media._ID,
                  MediaStore.Video.Media.DISPLAY_NAME,
                  MediaStore.Video.Media.DATA};
         String orderBy = MediaStore.Video.Media.DISPLAY_NAME;
         Uri uri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
         getContentProvider(uri,projection, orderBy);
     }

     /**
      * 获取音频列表
      */
     @Click
     void getAudio() {
         String []projection = { MediaStore.Audio.Media._ID,
                 MediaStore.Audio.Media.DISPLAY_NAME,
                 MediaStore.Audio.Media.DATA,
                 MediaStore.Audio.Media.SIZE};
         String orderBy = MediaStore.Audio.Media.DISPLAY_NAME;
         Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
         getContentProvider(uri,projection, orderBy);
     }

     /**
      * 获取ContentProvider
      * @param projection
      * @param orderBy
      */
     public void getContentProvider(Uri uri,String[] projection, String orderBy) {
         // TODO Auto-generated method stub
         List> listImage = new ArrayList>();
         Cursor cursor = getContentResolver().query(uri, projection, null,
                 null, orderBy);
         if (null == cursor) {
             return;
         }
         while (cursor.moveToNext()) {
             HashMap map = new HashMap();
             for(int i=0;i
                 map.put(projection[i], cursor.getString(i));
                 System.out.println(projection[i]+":"+cursor.getString(i));
             }
             listImage.add(map);
         }
         myTextView.setText(listImage.toString());
     }

 }

项目下载地址： http://download.csdn.net/detail/nuptboyzhb/7220227

扩展阅读：

【1】http://blog.csdn.net/gaomatrix/article/details/6216880

【2】http://developer.android.com/reference/android/content/ContentProvider.html