图片存储

if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) 
 {

if(image != null)
     {
            String sdardDir = Environment.getExternalStorageDirectory().toString();
            String name = sdardDir+"/appname/images/"+imagename+".jpg";
             java.io.File file = new java.io.File(sdardDir+"/appname/images");
             boolean bool = true;
             if(!file.isDirectory())
             {
                  bool = file.mkdirs() ; 
             }

if(bool)

{

File iamgeFile = new File(path);
             if(!iamgeFile.exists())
            {
              try {iamgeFile.createNewFile();} catch (IOException e1) {e1.printStackTrace();error= "1"+e1.toString(); }  
             }
             FileOutputStream fOut = null;   
             try {  fOut = new FileOutputStream(iamgeFile);   } catch (FileNotFoundException e) {  e.printStackTrace();
                 error= "2"+e.toString(); }  
  image.compress(Bitmap.CompressFormat.JPEG, 100, fOut);  // png格式图片 image.compress(Bitmap.CompressFormat.png, 100, fOut);
            try { fOut.flush();    } catch (IOException e) {   e.printStackTrace();  
              error="3"+ e.toString(); }   
            try { fOut.close();} catch (IOException e) {    e.printStackTrace(); 
             error= "4"+e.toString(); }

}

}

else{

Toast t = Toast.makeText(this, "无sdcard",  Toast.LENGTH_SHORT);
          t.show();

}

媒体库更新

- 通过 Intent.ACTION_MEDIA_MOUNTED 进行全扫描
public void allScan(){   
        sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"  
                + Environment.getExternalStorageDirectory())));   
    }

-  通过 Intent.ACTION_MEDIA_SCANNER_SCAN_FILE 扫描某个文件  
public void fileScan(String fName){   
         Uri data = Uri.parse("file:///"+fName);   
        sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, data));   
    }

详细

http://wenku.baidu.com/view/537b9b8ecc22bcd126ff0c97.html

http://devbbs.doit.com.cn/viewthread.php?tid=31528