Face detection with an option of video file input or using webcam (Java/JavaCV)

See more:

Java

OpenCV

I was wondering if anyone could help me out with this problem I'm having. I'm doing a face and eye detection using the webcam on my laptop.
I have two main classes that initialise the starting operation of opening the webcam and doing the detection :

FeaturesDetection class which implements JPanel and Runnable
This class has all the detection methods and override runnable
methods. Initially in my run() method I have this code below:

CvCapture grabber = opencv_highgui.cvCreateCameraCapture(CAMERA_ID);
    		opencv_highgui.cvSetCaptureProperty(grabber,
    				opencv_highgui.CV_CAP_PROP_FRAME_HEIGHT, 720);
    		opencv_highgui.cvSetCaptureProperty(grabber,
    				opencv_highgui.CV_CAP_PROP_FRAME_WIDTH, 1280);

Another class that implements JFrame and main method

When I run the project - the application will straight away load the webcam and the detection starts right away.

But now, I want to have an option in the beginning so user can either load a video file or choose webcam. So what I did was I added 2 buttons on jframe class
with actionlister attached to them. These two buttons then invoke their respective methods in the jpanel class.

JButton camBut = new JButton("Webcam");
    camBut.addActionListener( new ActionListener() {
       public void actionPerformed(ActionEvent e)
       { FeaturesDetection.webcam();  }
    });

    JButton vidBut = new JButton("Load Video");
    vidBut.addActionListener( new ActionListener() {
       public void actionPerformed(ActionEvent e)
       {

           JFileChooser chooser = new JFileChooser();
           int returnValue = chooser.showOpenDialog( null ) ;
           File file = null;
            if( returnValue == JFileChooser.APPROVE_OPTION ) {
                   file = chooser.getSelectedFile() ;
            }
            if(file != null)
            {
                filePath = file.getPath();
            }

           FeaturesDetection.videoFile(filePath);  }
    });

What I changed was, before the run() method has the above code that displays the webcam
instead I made an if statements that checks if user chose video file button or webcam button.

So in my updated run() method I have the following:

public void run()
   /*
    * display the current webcam image/vid */
   {

       // define a grabber
       if(webcam == true)
       {

           webcamCapture();
       }

       if(video == true)
       {

            vCapture();
       }


       if (grabber == null)
           return;

       long duration;
       isRunning = true;
       isFinished = false;

       while (isRunning) {
           long startTime = System.currentTimeMillis();

           img = cvQueryFrame(grabber);

           ……
           ………

       }
       // closeGrabber(grabber, CAMERA_ID);
       System.out.println("Execution End");
       isFinished = true;
   } // end of run()

In the loadwebcam() & loadVideo() I have :

public void loadwebcam()
      {
          webcam = true;
      }
  public void videoFile(String file)
      {
          video = true;
          vidInput = file;
      }

And in the method vCapture() and webcamCapture()
I have:

public CvCapture webcamCapture()
    {
        grabber = opencv_highgui.cvCreateCameraCapture(CAMERA_ID);
        opencv_highgui.cvSetCaptureProperty(grabber,
                opencv_highgui.CV_CAP_PROP_FRAME_HEIGHT, 720);
        opencv_highgui.cvSetCaptureProperty(grabber,
                opencv_highgui.CV_CAP_PROP_FRAME_WIDTH, 1280);
        return grabber;
    }

    public CvCapture vCapture()
    {
        grabber = opencv_highgui.cvCreateFileCapture(vidInput);
          opencv_highgui.cvSetCaptureProperty(grabber,
                  opencv_highgui.CV_CAP_PROP_FRAME_HEIGHT, 720);
          opencv_highgui.cvSetCaptureProperty(grabber,
                  opencv_highgui.CV_CAP_PROP_FRAME_WIDTH, 1280);

          return grabber;
    }

The problem that I have is that, when I click any of the two buttons nothing happens/ when I click on webcam button no webcam loads up? I'm not sure what I should add to fix this?
Any help please.
Thank you!