OnLongClickListener（）不在适配器类中启动

Question

在我的android PagerAdapter课程中，我定义了一个OnLongClickListener。但它在运行时无法正常工作。我无法在这里找到问题，任何帮助都会受到赞赏

码

public class FullScreenImageAdapter extends PagerAdapter {

    private Activity _activity;
    private ArrayList<String> _imagePaths;
    private LayoutInflater inflater;

    // constructor
    public FullScreenImageAdapter(Activity activity,
            ArrayList<String> imagePaths) {
        this._activity = activity;
        this._imagePaths = imagePaths;
    }

    @Override
    public int getCount() {
        return this._imagePaths.size();
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view == ((RelativeLayout) object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        TouchImageView imgDisplay;
        Button btnClose;

        inflater = (LayoutInflater) _activity
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View viewLayout = inflater.inflate(R.layout.layout_fullscreen_image, container,
                false);

        imgDisplay = (TouchImageView) viewLayout.findViewById(R.id.imgDisplay);
        btnClose = (Button) viewLayout.findViewById(R.id.btnClose);

        imgDisplay.setOnLongClickListener(new View.OnLongClickListener() {

            @Override
            public boolean onLongClick(View v) {
                // TODO Auto-generated method stub
                System.exit(0);
                return true;
            }
        });
        ImageLoader2 imageLoader = new ImageLoader2(_activity);       
        imageLoader.DisplayImage(_imagePaths.get(position), imgDisplay);

        // close button click event
        btnClose.setOnClickListener(new View.OnClickListener() {            
            @Override
            public void onClick(View v) {
                _activity.finish();
            }
        }); 

        ((ViewPager) container).addView(viewLayout);

        return viewLayout;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        ((ViewPager) container).removeView((RelativeLayout) object);

    }


}