flipflop cannot apply second material

Hey all
In my level blueprint I have set up a set of actions to make the squares change after being fired. In the last round of the program, the material will be rotated in turn. But the problem is that when I run the program, the program runs with a join, the material call “blue” cannot be displayed. Can I be Where can I do something wrong? Please help me.

Looks fine to me, are you sure the custom event change color is correct?

I am sorry to see it now. My “change color” setting is like this. Is there anything missing in my blueprint? I am a newbie.

289987-102.png

You don’t have a material selected…

I chose the material still does not work.

Did you manually change the Element index ? By default it is set to 0, check your mesh to be sure the good element is selected.

Yes, you also have to pass the material as a parameter to the custom event…

Oh and probably cast to the class you get to identify your static mesh component, too.

Yes I do,but the problem is that when I use “flipflop”, I can’t apply two materials at the same time.I refer to the article Set material - More than 1 element index? - Blueprint Visual Scripting - Unreal Engine Forums but still can’t execute

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