GUI: draw 2 point

Hi everyone!

I'm developing a GUI, and now I have a problem. When I push DRAW button I want to click two times on the image in the figure (loaded before) to drawing two point.

This is my code:

-----

 function pushbutton1_Callback(hObject, eventdata, handles)
 set(gcf, 'windowbuttondownfcn', @Draw0);

-----

 function Draw0(src,evnt)
 global x0 y0 
 pt = get(gca, 'CurrentPoint');
 x0 = pt(1, 1);
 y0 = pt(1, 2);

 hold on
 plot(x0,y0,'o','MarkerEdgeColor','k',...
               'MarkerFaceColor','r',...
               'MarkerSize',8)

----

When I execute my GUI and I press the button I can draw infinity points!! How can I do this? How can I interrupt the function? A function to draw just a point is right too...

Thanks a lot in advance.

Thanks in advance

Answer 1

[Matt Kindig]

One way to do it is to reset the callback 'windowbuttondownfcn' after two clicks. Something like this:

function pushbutton1_Callback(hObject, eventdata, handles)
  global numClicks
  numClicks = 0;
set(gcf, 'windowbuttondownfcn', @Draw0);

-----

 function Draw0(src,evnt)
 global x0 y0 numClicks
 pt = get(gca, 'CurrentPoint');
 x0 = pt(1, 1);
 y0 = pt(1, 2);
 numClicks=  numClicks+1;

 hold on
 plot(x0,y0,'o','MarkerEdgeColor','k',...
               'MarkerFaceColor','r',...
               'MarkerSize',8)
  if numClicks > 2,
    set(src, 'windowbuttondownfcn', '');
end

[Pinco]

It works perfectly!!!

Thank you very very very much!!