How Do I avoid Reference Error by Ordering Initialization order?

🌵 Needle Engine
21

Hello Ken2,

To access EventList on a parent component from a child class in the Needle Engine, you can use methods like getComponentInParent to find the EventList component. Here’s a step-by-step plan and code example:

  1. Define a class that extends Behaviour.
  2. Use the start lifecycle method to access the parent EventList component.
  3. If the EventList is not found, handle accordingly (either by warning or taking alternative action).
import { Behaviour, EventList } from '@needle-tools/engine';
// Import other required modules...

export class ChildComponent extends Behaviour {

    private eventList: EventList | null;

    start() {
        // Attempt to find the EventList component in the parent
        this.eventList = this.gameObject.getComponentInParent(EventList);

        // Check if the EventList was found
        if (!this.eventList) {
            console.error("EventList component not found on the parent.");
            // Handle the absence of the EventList component appropriately
        }
    }
    
    // Other methods...
}

Ensure that the EventList component is indeed on the parent GameObject and that the hierarchy is correctly set up in the Inspector tab. If you keep encountering problems or if you feel there’s a deeper issue with the Inspector not displaying the EventList, you might want to check for any UI bugs or reach out for support with complete details of your setup.

1 messages left GPT 4
thread_i855XB0u1mmXkzHP1pGViL6h
Thanks for your feedback!

22

@Needle Engine Assistant I mean the parent class is not
hierarchical set to Transforms in Unity as transform sturucture then it is from the typescript side that are separated in two class one derives the parent class that has Eventlist as a instance variable.

by user 151660356224286721

23

Here is what I found for you :brain: Discord

24

Are you saying that the EventList is a property of the parent class and you want to access it from the child class in TypeScript? If so, you can utilize TypeScript’s advanced type system and access the parent class’s EventList property from the child class. Here’s an example of how you might do this:

export class ParentComponent extends Behaviour {
    eventList: EventList | null;

    // ...
}

export class ChildComponent extends Behaviour {
    start() {
        // Access the parent object
        const parentObject = this.gameObject.parent;
  
        if (parentObject) {
            // Access the eventList property from the parent object
            const eventList = (parentObject.getComponent(ParentComponent) as ParentComponent).eventList;
            if (eventList) {
                // Use the eventList property as needed
            }
        }
    }
  
    // Other methods...
}

In this example, we access the ParentComponent using this.gameObject.parent. Then, we cast the parent component to ParentComponent to access its eventList property in the ChildComponent. However, if the structure is more complex, you may need to traverse the parent hierarchy or further specify your requirements.

0 messages left GPT 3.5
thread_i855XB0u1mmXkzHP1pGViL6h
Thanks for your feedback!

25

Can you share your code? Is the eventlist public?

26

Hi thanks for reply, I just changed the eventList to function and did the direct referencing and it worked! thank you

by user 151660356224286721