# InerfaceCast returns null for blueprint classes implementing that interface

**URL:** <https://forums.unrealengine.com/t/inerfacecast-returns-null-for-blueprint-classes-implementing-that-interface/283213>\
**Category:** Feedback & Requests\
**Tags:** unreal-engine, documentation, CPP, Blueprint, question\
**Created:** [May 13, 2014, 8:58am UTC](https://forums.unrealengine.com/t/inerfacecast-returns-null-for-blueprint-classes-implementing-that-interface/283213 "2014-05-13T08:58:01Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![anonymous\_user\_b666e59e](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b666e59e](https://forums.unrealengine.com/u/anonymous_user_b666e59e)\
**Post date:** [May 13, 2014, 5:23pm UTC](https://forums.unrealengine.com/t/inerfacecast-returns-null-for-blueprint-classes-implementing-that-interface/283213/2 "2014-05-13T17:23:21Z")

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Hi . I am little unsure about exactly what you are trying to do in a couple lines of your code sample. In line 36, it looks like you are creating a pointer named `ListenerInterface`, and setting the value to `NULL`. Then, in line 42, you are checking the see if `ListenerInterface` contains a valid value, which it does not since it is still `NULL`, so the following line never triggers.

Is your InterfaceCast in line 39 supposed to be updating the value stored in `ListenerInterface`? If you can clarify what those lines are trying to do, I can look into this a bit more for you.

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