android 扫描SDCard.

//android 扫描SDCard.

sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, 
 Uri.parse("file://" + Environment.getExternalStorageDirectory().getAbsolutePath())));

//注册

IntentFilter f = new IntentFilter();
 f.addAction(Intent.ACTION_MEDIA_SCANNER_STARTED);
 f.addAction(Intent.ACTION_MEDIA_SCANNER_FINISHED);
 f.addAction(Intent.ACTION_MEDIA_UNMOUNTED);
 f.addDataScheme("file");
 registerReceiver(mScanListener, f);