Adobe Animate ActionScript 3 Error 1009 for a MovieClip - actionscript-3

Question

I am writing code to have enemies detect collision with the player. In my Enemy class I have the following:
import flash.display.MovieClip;
import flash.events.Event;
public class Enemy extends MovieClip {
var Player: MovieClip;
public function Enemy() {
this.addEventListener(Event.ENTER_FRAME, EnemyUpdate);
}
function setPlayer(_Player: MovieClip) {
Player = _Player;
}
function EnemyUpdate(_event: Event) {
var enemyHit: Boolean = this.hitTestObject(Player.Character.Legs);
if (enemyHit) {
trace("OUCH!!");
}
}
}
In my Main Class, I attempt to send the Player MovieClip to the Enemy Class script using the following:
public function Main() {
enemy.setPlayer(player);
}
The MovieClip enemy has the Enemy script attached to it. When I run the program, the Player variable is null. How do I get the Player to recognize the Player MovieClip?

Answer 1

This happens because you set your player after an Enemy had been instantiated. In Enemy constructor you have EnterFrame listener. To fix the error change your code as follows:
public function Enemy() {
// empty constructor, you can remove it if there is no other logic in it
}
function setPlayer(_Player: MovieClip) {
Player = _Player;
// the Player variable is not null anymore.
this.addEventListener(Event.ENTER_FRAME, EnemyUpdate);
}