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HoloToolkit - NullReferenceException - cant find the error

edited September 2016 in Questions And Answers

Hi guys,

i'm trying to build a simple app, where you gaze and tap at an object to let it rotate.
Im using Unity, Vuforia and the Holo Toolkit.

If i try my app in Vuforias "playmode", everything works fine. However, if i deploy the project on the HoloLens, Visual Studio just spams this message out (while nothing is happening in the app):

NullReferenceException: Object reference not set to an instance of an object. at HoloToolkit.Unity.GazeManager.Update() at HoloToolkit.Unity.GazeManager.$Invoke15Update(Int64 instance, Int64* args) at UnityEngine.Internal.$MethodUtility.InvokeMethod(Int64 instance, Int64* args, IntPtr method) (Filename: <Unknown> Line: 0)

This is the "Upadte()":

private void Update()
            gazeOrigin = Camera.main.transform.position;
            gazeDirection = Camera.main.transform.forward;

And on this image, you can see my Unity-setup:

Is this a known problem/is there a workarround? Did i miss something?
Help would be appreciated.


1.JPG 142.8K


  • Some object reference is not initialized or set properly.

    Use Debug.Log("your custom messages to check object references") statements to find it.

    Could be in one of the method calls in the Update routine you show.

  • Ok, i found out, that the problem only appears, if i start using Vuforia.

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