title: Why does the ButtonDownFcn callback of my axes object stop working after plotting something?
body: <p>I'm creating a set of axes in a figure and assigning a callback for its <code>'ButtonDownFcn'</code> property like so:</p>
  
  <pre><code>HRaxes = axes('Parent', Figure, 'Position', [.05 .60 .9 .35],...
                'XLimMode', 'manual', 'ButtonDownFcn', @HR_ButtonDown);
  </code></pre>
  
  <p>Where the callback function is defined as such:</p>
  
  <pre><code>function HR_ButtonDown(hObject, eventData)
    %# Do some stuff here when the axes is clicked on...
  end
  </code></pre>
  
  <p>The callback works fine until I plot something on the axes like so:</p>
  
  <pre><code>plot(HRaxes, data.HR_X, data.HR_Y, 'b');
  </code></pre>
  
  <p>After which the callback doesn't trigger anymore when I click on the axes. What's going wrong and how can I fix it?</p>