How to handle collission end in arcade physics

Hello. I have a problem : i dont know how to handle collision end in arcade physics. I need to show icon, when player overlap with game object, so i tried this :

create() {
        this.objCollide = true;

update() {

It works, but when i collide with obj, icon starts flicker, because update set alpha 0, but then after millisecond set alpha 1. I dont like this flicker effect. So how i can do something like that : this.physics.add.overlapEnd(this.player,this.obj) ?