Drag and drop Image by axes attachment

I am creating a gui involving drag and dropping images. I can drag axes and attach images using imshow however the dragging functionality is lost upon attachment. What is the reason for this? With some other online help here is the code I used:

%drawing axes and attaching figure

ax = axes('Parent',tab3,'Position',[.15 .15 .1 .1],'ButtonDownFcn',@dragObject);
handles = guihandles(ax);
img=imread('Cyclindrical.PNG');
imshow(img,'parent',ax,'ButtonDownFcn',@dragObject);

grab and drag functions are as follows:

function dragObject(hObject,eventdata)
        dragging = hObject;
        oldPos = get(gcf,'CurrentPoint');
        disp(oldPos)
    end

      function dropObject(hObject,eventdata)
          if ~isempty(dragging)
              newPos = get(gcf,'CurrentPoint');
              dPos = newPos - oldPos;
              set(dragging,'Position',get(dragging,'Position') + [dPos(1:2) 0 0]);
              dragging = [];
          end
      end

[Skander Ayoub]

Hi Jonathan,

Did you manage to solve your problem ? I am also facing this issue.