title: How do i end an ongoing mouseevent in fabricjs
body: <p>i am trying to achieve a collision detection with fabricjs. 
  In the <a href="http://codepen.io/anon/pen/PwQbRQ" rel="nofollow">example</a> i'm providing, the blue ball should not be able to cross the red line. The collision detection works fine, but i cant figure out how to end the dragging once the collision takes place. </p>
  
  <p>I tryed to change the balls options (i commented it out in the example) but all changes, including:    </p>
  
  <pre><code>canvas.deactivateAllWithDispatch();  
  </code></pre>
  
  <p>are for the next mouse event, but doesnt affect the currently running one.
  How do i end the currently ongoing mouse event?</p>
  
  <p>example:
  <a href="http://codepen.io/anon/pen/PwQbRQ" rel="nofollow">http://codepen.io/anon/pen/PwQbRQ</a></p>