Unity3d class that inherits from button and add OnHold Event

Question

I made my own class that inherits from button and has an OnHold event. It seems to work ok but I'm wondering if I can improve it or if you can spot any glaring mistakes that I made.

Here is the code:

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using UnityEngine.Events;
[AddComponentMenu("UI/Hold Button")]
public class HoldButton : Button
{
    private bool isBeingPressed;
    private float currTime;
    private static float TimeMax = 2;
    private bool startTimer;
    public ButtonHoldEvent onHold { get; set; }
    public override void OnPointerDown(PointerEventData eventData)
    {
        startTimer = true;
        currTime = 0;
    }
    public override void OnPointerUp(PointerEventData eventData)
    {
        startTimer = false;
        currTime = 0;
        isBeingPressed = false;
    }
    void Update()
    {
      if(startTimer)
        {
            currTime += Time.deltaTime;
            if(currTime >= TimeMax)
            {
                isBeingPressed = true;
            }else
            {
                isBeingPressed = false;
            }
        }
        if (isBeingPressed)
        {
            onHold.Invoke(); 
        }
    }

    public class ButtonHoldEvent : UnityEvent
    {
        public ButtonHoldEvent() : base()
        {

        }
    }
}

Answer 1

There is a few thing you can improve :

• TimeMax is used like a constant here, but is not given the access modifier const.

• Try to group your class members in a meaningful way. It could depend on their function(member of same interface), access-modifier, or what makes sense to you.

  public ButtonHoldEvent onHold { get; set; }
  
  private static float TimeMax = 2;
  
  private bool isBeingPressed;
  private float currTime;
  private bool startTimer;
  

• The name currTime doesn't reflect what it contains. heldDuration is more appropriate. The same applies for TimeMax and should be renamed TriggerTime.

• isPressed is fine, but isHeldDown fits more the theme here.

---

Full code :

[AddComponentMenu("UI/Hold Button")]
public class HoldButton : Button
{
    public ButtonHoldEvent onHold { get; set; }

    private const float TriggerTime = 2;

    private bool isHeldDown;
    private float heldDuration;

    public override void OnPointerDown(PointerEventData eventData)
    {
        isHeldDown = true;
        heldDuration = 0;
    }
    public override void OnPointerUp(PointerEventData eventData)
    {
        isHeldDown = false;
        heldDuration = 0;
    }

    void Update()
    {
        if (!isHeldDown)
        {
            heldDuration += Time.deltaTime;

            if (heldDuration >= TriggerTime)
            {
                onHold.Invoke();

                // uncomment next line, to make `onHold` trigger only once per mouse press-hold
                //isHeldDown = false;
            }
        }
    }

    public class ButtonHoldEvent : UnityEvent
    {
        public ButtonHoldEvent() : base()
        {

        }
    }
}