if statement not working

Unity Engine
,
1 
public class PlayerInventory : MonoBehaviour
{
    public int NumberOfBalls { get; private set; }

    public UnityEvent<PlayerInventory> OnBallCollected;

    public OpenDoor openDoor;

    public int ballNumber = 6;

    public void BallCollected()
    {
        NumberOfBalls++;
        OnBallCollected.Invoke(this);
    }
    void Update()
    {
        if (NumberOfBalls == ballNumber)
        {
            openDoor.GetComponent<OpenDoor>().Open();
        }
    }
}

For some reason if (NumberOfBalls == ballNumber) is called even if the NumberOfBalls collected is not equal to ballNumber. So openDoor.GetComponent<OpenDoor>().Open(); keeps getting executed before it should. Any ideas?

2

For some reason? Here’s how you can find that reason!

You must find a way to get the information you need in order to reason about what the problem is.

What is often happening in these cases is one of the following:

  • the code you think is executing is not actually executing at all
  • the code is executing far EARLIER or LATER than you think
  • the code is executing far LESS OFTEN than you think
  • the code is executing far MORE OFTEN than you think
  • the code is executing on another GameObject than you think it is
  • you’re getting an error or warning and you haven’t noticed it in the console window

To help gain more insight into your problem, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

  • is this code even running? which parts are running? how often does it run? what order does it run in?
  • what are the values of the variables involved? Are they initialized? Are the values reasonable?
  • are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

Knowing this information will help you reason about the behavior you are seeing.

If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer or iOS: https://discussions.unity.com/t/700551 or this answer for Android: https://discussions.unity.com/t/699654

Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

https://discussions.unity.com/t/839300/3

1 Like
3

You said it is executed every frame. So we assume you have actually checked that, right? Something like this:

    void Update()
    {
        if (NumberOfBalls == ballNumber)
        {
            Debug.Log("NumberOfBalls: "+NumberOfBalls, gameObject);
            openDoor.GetComponent<OpenDoor>().Open();
        }
    }

If you don’t see this log every frame, it is not executed every frame. We don’t know what that Open method actually does, but keep in mind as soon as the two variables are actually equal, you would call Open every frame as long as the two numbers are equal.

If you only want to call the method once, you could replace your auto property with this one:

private int m_NumberOfBalls;
public int NumberOfBalls
{
    get => m_NumberOfBalls;
    private set
    {
        m_NumberOfBalls = value;
        if (NumberOfBalls == ballNumber)
        {
            openDoor.GetComponent<OpenDoor>().Open();
        }
    }
}

With that you can get rid of the Update method all together

1 Like
4

I think I should’ve explained myself a little better, I was tired, sorry.
Yes, I had checked if it was being executed, I put a debug log inside of the if statement and it wasn’t crossed unless ballNumber and NumberOfBalls were equal. In game, that means a door would open if the player collected ballNumber of balls. Problem is openDoor.GetComponent().Open(); , which is what should open the door, gets triggered regardless of if ballNumber and NumberOfBalls are equal or not. That’s the part that confuses my begginer brain. If you have any questions please ask.

Also, thanks for the second part of the reply, that’s exactly what I was looking for, getting rid of update. Although I’m not sure how to implement your example. If you could copy and paste it in my original script that would be very helpful.
Thanks!

5

Thanks for the extensive reply! Debug.Break() is exactly what I was looking for the other day and I didn’t know how to write it!

6

I solved it by putting the if statement in the OpenDoor script, it’s more of a work around but whatever. I would love to know this:
Also, thanks for the second part of the reply, that’s exactly what I was looking for, getting rid of update. Although I’m not sure how to implement your example. If you could copy and paste it in my original script that would be very helpful.
Thanks!
, it would be quite helpful