How do I check character is grounded?

I have my own platform movement eventsheet. I made it but I can not do one small thing. Each character chas a isgrounded variable this is a bool type variable.

How can I check whether a character in conflict with whether or not ground?

The platform behavior has an "Is on floor" condition that will let you know if your object is on the ground.

I dont want use behaviours.

A want make on floor function in my own platform character controller event sheet.

I will use on collision event if i want making own on floor function? Or something else solution somebody guys?

Probably a detector sprite below the player or using the "overlaps at offset" condition.