title: Unity UI canvas not working with VR
body: <p>I have been trying to get a very simple demo of a native Unity UI canvas working with VR.</p>
  
  <p>I have read the oculus blog post here: <a href="https://developer3.oculus.com/blog/unitys-ui-system-in-vr/" rel="nofollow noreferrer">https://developer3.oculus.com/blog/unitys-ui-system-in-vr/</a> but i need to use the native unity UI as i want to redistribute the code without license worries.I followed this tutorial <a href="https://unity3d.com/learn/tutorials/topics/virtual-reality/interaction-vr?playlist=22946" rel="nofollow noreferrer">https://unity3d.com/learn/tutorials/topics/virtual-reality/interaction-vr?playlist=22946</a> and downloaded the unity vr samples project from the asset store. In this they provide some scripts to place on the camera (VRInput and VREyeRaycaster) and some scripts to place on the target object (VRInteractiveItem and ExampleInteractiveItem).</p>
  
  <p>When i apply the target scripts to a regular GameObject in the scene (e.g. a cube) the raycast works fine and the appropriate calls are made when fire1 is activated. When i try and do this for a canvas object (e.g. a button) - no hit is detected. I have tried placing the two target scripts (VRInteractiveItem and ExampleInteractiveItem) on the canvas, the image containing the button and the button itself and none work. What am i doing wrong? Why would it work on a regular gameobject and not on a UI canvas? I have made sure all my canvas elements have their raycast target boolean property ticked</p>
  
  <p>EDIT:
  It seems to work when i attach a box collider to the UI element, is this required? i thought it should just work with a GraphicsRaycaster attached. but the configuration below doesn't work (when box collider is disabled and graphics raycaster is enabled)</p>
  
  <p><a href="https://i.stack.imgur.com/E20TZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/E20TZ.png" alt="enter image description here"></a></p>
  
  <p>This is what is on my players camera:</p>
  
  <p><a href="https://i.stack.imgur.com/7xmw8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7xmw8.png" alt="enter image description here"></a></p>
  
  <p>I dont have a problem using box colliders if i have to but i wanted to take advantage of the UI buttons changes in highlighted and pressed color properties</p>