Thank you for reporting this issue. I have checked the situation and indeed we have missed adding the implementation of this specific class. You can find it in the code for the "Data Filter Custom Editors"
demo. We will update the demo in the near future so that it has all the information needed. Please, check if this implementation suits your project needs and update me if you need any assistance.
Of course, if you have any further questions or concerns, do not hesitate to contact us as well.
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