Resources  r = getResources();

Uri uri =  Uri.parse(ContentResolver.SCHEME_ANDROID_RESOURCE + "://"

   + r.getResourcePackageName(R.drawable.ic_launcher) + "/"

   + r.getResourceTypeName(R.drawable.ic_launcher) + "/"

   + r.getResourceEntryName(R.drawable.ic_launcher));

defaultAppPic= uri.getPath()