android - How to modify zxing for keeping on scanning? -

i have developed application qr code scanner based on zxing,but facing problem how modify code scanner can keep on scan s sequence of qr code data until user stopped it. can give me advice?

public class scanlibrarycardactivity extends captureactivity { private progressdialog pdialog; private string uid, bname, authors, publisher, edition, callnumber,         location; private int total; jsonparser jparser = new jsonparser(); jsonarray user = null;  @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     // setcontentview(r.layout.main);     // cameramanager }  @override public void handledecode(final result obj, bitmap barcode) {      uid = obj.gettext();     if (uid.matches("\\d+"))         new checkcorrectuser().execute();     else {         customizeddialog.showresultdialog(scanlibrarycardactivity.this,                 "invalid user");         intent = new intent(getapplicationcontext(),scanlibrarycardactivity.class);         i.addflags(intent.flag_activity_no_animation);         i.addflags(intent.flag_activity_clear_top);         startactivity(i);         finish();     } }  class checkcorrectuser extends asynctask<string, string, string> {     int success;      /**      * before starting background thread show progress dialog      * */      @override     protected void onpreexecute() {         super.onpreexecute();         pdialog = new progressdialog(scanlibrarycardactivity.this);         pdialog.setmessage("loading. please wait...");         pdialog.setindeterminate(false);         pdialog.setcancelable(false);         pdialog.show();     }      protected string doinbackground(string... args) {         // building parameters         list<namevaluepair> params = new arraylist<namevaluepair>();         params.add(new basicnamevaluepair(tag.gettaguid(), uid));         jsonobject json = jparser.makehttprequest(url.geturl_getuserdata(),                 "get", params);         try {             // checking success tag             success = json.getint(tag.gettagsuccess());              if (success == 1) {                  user = json.getjsonarray("user");                 jsonobject c = user.getjsonobject(0);                 total = c.getint("total");             } else {                 // error pop-up             }         } catch (jsonexception e) {             e.printstacktrace();         }          return null;     }      protected void onpostexecute(string file_url) {         // dismiss dialog after getting products         pdialog.dismiss();         // updating ui background thread         runonuithread(new runnable() {             public void run() {                 if (success == 1) {                     customizeddialog.showresultdialog(                             scanlibrarycardactivity.this, "valid user");                 } else {                     // allow user function without save                     // data                     customizeddialog.showresultdialog(                             scanlibrarycardactivity.this, "invalid user");                 }              }          });     } }  }    public class captureactivity extends activity implements callback {  private captureactivityhandler handler; private viewfinderview viewfinderview; private boolean hassurface; private vector<barcodeformat> decodeformats; private string characterset; private inactivitytimer inactivitytimer; private mediaplayer mediaplayer; private boolean playbeep; private static final float beep_volume = 0.10f; private boolean vibrate;  /** called when activity first created. */ @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.main);     // cameramanager     cameramanager.init(getapplication());     viewfinderview = (viewfinderview) findviewbyid(r.id.viewfinder_view);     hassurface = false;     inactivitytimer = new inactivitytimer(this);  }  @override protected void onresume() {     super.onresume();     surfaceview surfaceview = (surfaceview) findviewbyid(r.id.preview_view);     surfaceholder surfaceholder = surfaceview.getholder();     if (hassurface) {         initcamera(surfaceholder);     } else {         surfaceholder.addcallback(this);         surfaceholder.settype(surfaceholder.surface_type_push_buffers);     }     decodeformats = null;     characterset = null;      playbeep = true;     audiomanager audioservice = (audiomanager) getsystemservice(audio_service);     if (audioservice.getringermode() != audiomanager.ringer_mode_normal) {         playbeep = false;     }     initbeepsound();     vibrate = true; }  @override protected void onpause() {     super.onpause();     if (handler != null) {         handler.quitsynchronously();         handler = null;     }     cameramanager.get().closedriver(); }  @override protected void ondestroy() {     inactivitytimer.shutdown();     super.ondestroy(); }  private void initcamera(surfaceholder surfaceholder) {     try {         cameramanager.get().opendriver(surfaceholder);     } catch (ioexception ioe) {         return;     } catch (runtimeexception e) {         return;     }     if (handler == null) {         handler = new captureactivityhandler(this, decodeformats,                 characterset);     } }  @override public void surfacechanged(surfaceholder holder, int format, int width,         int height) {  }  @override public void surfacecreated(surfaceholder holder) {     if (!hassurface) {         hassurface = true;         initcamera(holder);     }  }  @override public void surfacedestroyed(surfaceholder holder) {     hassurface = false;  }  public viewfinderview getviewfinderview() {     return viewfinderview; }  public handler gethandler() {     return handler; }  public void drawviewfinder() {     viewfinderview.drawviewfinder();  }   public void handledecode(final result obj, bitmap barcode) {     inactivitytimer.onactivity();     playbeepsoundandvibrate();  }  private void initbeepsound() {     if (playbeep && mediaplayer == null) {         // volume on stream_system not adjustable, , users found         // loud,         // play on music stream.         setvolumecontrolstream(audiomanager.stream_music);         mediaplayer = new mediaplayer();         mediaplayer.setaudiostreamtype(audiomanager.stream_music);         mediaplayer.setoncompletionlistener(beeplistener);          assetfiledescriptor file = getresources().openrawresourcefd(                 r.raw.beep);         try {             mediaplayer.setdatasource(file.getfiledescriptor(),                     file.getstartoffset(), file.getlength());             file.close();             mediaplayer.setvolume(beep_volume, beep_volume);             mediaplayer.prepare();         } catch (ioexception e) {             mediaplayer = null;         }     } }  private static final long vibrate_duration = 200l;  private void playbeepsoundandvibrate() {     if (playbeep && mediaplayer != null) {         mediaplayer.start();     }     if (vibrate) {         vibrator vibrator = (vibrator) getsystemservice(vibrator_service);         vibrator.vibrate(vibrate_duration);     } }  /**  * when beep has finished playing, rewind queue one.  */ private final oncompletionlistener beeplistener = new oncompletionlistener() {     public void oncompletion(mediaplayer mediaplayer) {         mediaplayer.seekto(0);     } };   }