How can I call a event from actor blueprint in level blue print

Here is the thing:
I create a custom event in a actor blueprint call “change color” to change the color of box.
Here is my material and actor bp setting

And I want this process could happen when press “B” button.
Here is my level setting(But it doesn’t work)

How can I do that? Do I missing something?

Is there a reason you want to use the lvl-BP?

I would recommend you to check this tutorial out:

UE4 - Tutorial - Dynamic Materials in BluePrints! (Request!) - YouTube


And This Link:


Did you set your inputs? If you connect the B event to a ‘Print String’ does that actually print something? If not, set ‘Auto Receive Input’ in Class Defaults to ‘Player 0’.

However, as the other answer points out, that functionality doesn’t really belong in the level blueprint.

Specify your material when creating the Dynamic Material Instance.