Problem: System.DllNotFoundException

[Siavash Mortazavi]

Hi, I’m trying to use EyeX SDK and EyeX eye tracker. I have added Tobii.EyeX.Client.Net20.dll and EyeXFramework.dll as references. When I run my application, it does nothing, and when I try to close it, I receive this error message:

An unhandled exception of type ‘System.DllNotFoundException’ occurred in Tobii.EyeX.Client.Net20.dll

Additional information: Unable to load DLL ‘Tobii.EyeX.Client.dll’: The specified module could not be found. (Exception from HRESULT: 0x8007007E)

I have tried different versions of dlls (x86 and x64) and also I have tried to compile my app with different CPU configurations. The problem exist on both Windows 7 64-bit and Windows 8.1 64-bit.

Basically, I would like to access the gaze stream in a WPF application, and update my app based on gaze location. I don’t need to use any WPF-specific feature here.

Can anyone help please?

Thanks,
Sia

[Siavash Mortazavi]

UPDATE: after this line of code in my app gets executed:
var eyeXHost = new EyeXHost();

then, eyeXHost object has this status:
_context: {Tobii.EyeX.Client.Context}
_dataStreams: Count = 1
_deletedDataStreams: Count = 0
_displaySizeStateAccessor: {EyeXFramework.EngineStateAccessor<Tobii.EyeX.Client.Size2>}
_environment: {Tobii.EyeX.Client.Environment}
_eyeTrackingDeviceStatusStateAccessor: {EyeXFramework.EngineStateAccessor<Tobii.EyeX.Framework.EyeTrackingDeviceStatus>}
_screenBoundsStateAccessor: {EyeXFramework.EngineStateAccessor<Tobii.EyeX.Client.Rect>}
_userPresenceStateAccessor: {EyeXFramework.EngineStateAccessor<Tobii.EyeX.Framework.UserPresence>}
_userProfileNameStateAccessor: {EyeXFramework.EngineStateAccessor<string>}
DisplaySize: {INVALID}
EyeTrackingDeviceStatus: {INVALID}
ScreenBounds: {INVALID}
UserPresence: {INVALID}
UserProfileName: {INVALID}

[Siavash Mortazavi]

Can anyone please download my very simple source code and tell me what is the problem?
The main logic happens in TobiiController.cs
https://onedrive.live.com/redir?resid=2681762D21DAF94D%219087

[Siavash Mortazavi]

UPDATE: I have solved the .dll problem, but still the I cannot get any data from eyeXhost object.

[Robert [Tobii]]

Hi Sia,

I looked briefly in your sample code. It looks like one problem is the using statements:

            using (var eyeXHost = new EyeXHost())
            {
                eyeXHost.Start();

                using (var stream = eyeXHost.CreateGazePointDataStream(GazePointDataMode.LightlyFiltered))
                {
                 // ...

This means that the EyeXHost and data stream instances will be disposed right afterwards. You need to save a reference to the EyeXHost and stream object, and only dispose them when you dispose your TobiiController instance.

See MSDN for best practices regarding the using statement and IDisposable:
http://msdn.microsoft.com/en-us/library/fs2xkftw.aspx
http://msdn.microsoft.com/en-us/library/yh598w02.aspx

[Siavash Mortazavi]

Hi @roberttobii

Thank you so much!
You’re right, I was making a stupid mistake! 😀

Best,
Sia

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