Observer Pattern in Unity (C# Programming Pattern)

Research System Setup (Observer Pattern)

Programming Pattern: Observer Pattern

UI Setup

The ResearchBaseObjectUIData class is a data container that holds UI-related references. (like TextMeshPro Component, or the Icon Image Component)

using UnityEngine;

public class ResearchBaseObjectUI : MonoBehaviour
{

    public ResearchBaseObjectUIData UIData;

    public void Assign(ResearchBaseSO so)
    {
        if (!UIData.IsEmpty())
        {
            UIData.IconImage.sprite = so.Icon;
            UIData.Title.text = so.Name;
            UIData.Description.text = so.Description;
            UIData.Stars.text = "";
        }

        so.OnResearchCompleted += Complete;
    }

    private void Complete()
    {
        UIData.Stars.text += "+";
    }
}

Let’s generate research objects.

At the moment there are only UI assigments. ResearchBaseSO contains research data.

Our Research Controller contains a list of ResearchBaseSO.

Lets spawn an object out of that list. Then store it somewhere. To access the spawned object, store it inside the ResearchController.

ResearchController contains a reference to the Base UI Prefab to instantiate and to assign scriptable objects to each instance:

using System.Collections.Generic;
using UnityEngine;

public class ResearchController : MonoBehaviour
{
    public List<ResearchBaseSO> researchList;
    [SerializeField] private GameObject researchPrefab;

    private void Start()
    {
        foreach (ResearchBaseSO research in researchList)
        {
            Instantiate(researchPrefab);
            researchPrefab.GetComponent<ResearchBaseObjectUI>().Assign(research);
        }
    }

}

Also a list to store spawned objects is required, and a container to display ui objects properly:

using System.Collections.Generic;
using UnityEngine;

public class ResearchController : MonoBehaviour
{
    public List<ResearchBaseSO> researchList;
    [SerializeField] private GameObject researchPrefab;
    [SerializeField] private Transform container;


    private List<ResearchBaseObjectUI> storedResearchObjects = new List<ResearchBaseObjectUI>();

    private void Start()
    {
        foreach (ResearchBaseSO research in researchList)
        {
            ResearchBaseObjectUI instance = Instantiate(researchPrefab, container).GetComponent<ResearchBaseObjectUI>();
            instance.Assign(research);
            storedResearchObjects.Add(instance);
        }
    }

}

voilá – first research item:

Nice. Let’s clean the code. „#region #endregion“ is a nice way to wrap code.