How to scan SD card for particular extension of files in android?

Question

I am working on a project which contains a module to scan pdf, doc xls files from sd card and make list of them. I also want to make list of folders only.

As I am very new to android. Anyone have idea of achieving this.

Here is my code:

public class MediaScannerWrapper implements  
MediaScannerConnection.MediaScannerConnectionClient {
    private MediaScannerConnection mConnection;
    private String mPath;
    private String mMimeType;

    // filePath - where to scan; 
    // mime type of media to scan i.e. "image/jpeg". 
    // use "*/*" for any media
    public MediaScannerWrapper(Context ctx, String filePath, String mime){
        mPath = filePath;
        mMimeType = mime;
        mConnection = new MediaScannerConnection(ctx, this);
    }

    // do the scanning
    public void scan() {
        mConnection.connect();
    }

    // start the scan when scanner is ready
    public void onMediaScannerConnected() {
        mConnection.scanFile(mPath, mMimeType);
        Log.w("MediaScannerWrapper", "media file scanned: " + mPath);
    }

    public void onScanCompleted(String path, Uri uri) {
        // when scan is completes, update media file tags
    }
}

Answer 1

public void walkdir(File dir) {
    String pdfPattern = ".pdf";

    File[] listFile = dir.listFiles();

    if (listFile != null) {
        for (int i = 0; i < listFile.length; i++) {

            if (listFile[i].isDirectory()) {
                walkdir(listFile[i]);
            } else {
              if (listFile[i].getName().endsWith(pdfPattern)){
                              //Do what ever u want

              }
            }
        }
    }    }

To search on the whole sdcard call this function usingwalkdir(Environment.getExternalStorageDirectory());