3.3.1碰撞回调报错？

Creator 3.x
#1

用3.3.1做2d
按照官方文档 来写的。
debug.ts:102 TypeError: Cannot read properties of null (reading ‘on’)

let collider = this.node.getComponent(Collider);

    collider.on("onTriggerStay", this.onTrigger,this);

private onTrigger(event: ITriggerEvent) {

    console.log(event.type, event);

}
#2

let collider = this.node.getComponent(Collider2D);
2d的碰撞体和3d的碰撞体的类名字要区分好

#3

还是不行。 Collider2D 的on函数 定义参数是
cocos_core_event_eventify_EventType
但是他的值 是
export type cocos_core_event_eventify_EventType = string | number;
用字符串
var collider = this.node.getComponent(Collider2D);

    collider.on("onTriggerEnter", this.onTriggerEnter, this);

    collider.on("onTriggerStay", this.onTriggerStay, this);

    collider.on("onTriggerExit", this.onTriggerExit, this);

    collider.on("onCollisionEnter", this.onCollisionEnter, this);

    collider.on("onCollisionStay", this.onCollisionStay, this);

    collider.on("onCollisionExit", this.onCollisionExit, this);

没有产生回调，
用number 0-10 也没有产生回调。