File type checking for HelloGallery

In the previous article, HelloGallery, read picture files from SD, using File ArrayList, the application view all files, no matter what type it is. Here, add a conditional checking for file type, by checking on the extension. Only files with extension jpg, gif and png will be added in the File ArrayList. Such change involve modification of the method ReadSDCard() only.

private List<String> ReadSDCard()
{
List<String> tFileList = new ArrayList<String>();

//It have to be matched with the directory in SDCard
 File f = new File("/sdcard/pictures/");

 File[] files=f.listFiles();

 for(int i=0; i<files.length; i++)
 {
  File file = files[i];

     String curFile=file.getPath();
     String ext=curFile.substring(curFile.lastIndexOf(".")+1, 
       curFile.length()).toLowerCase();
     if(ext.equals("jpg")||ext.equals("gif")||ext.equals("png"))
   tFileList.add(file.getPath());
 }

 return tFileList;
}