Turning on a UnityUI Menu triggers OnEnable\OnDisable methods multiple times

LostTrainDude

[Unity v2019.4.26f1 - AC v1.73.7]

Hi Chris!

While trying to create a more complex UI, using Unity UIs as a Menu source, I noticed that when the Menu first gets turned on, the OnEnable\OnDisable scripts attached to my Panels get triggered in (to me) unexpected ways.

I successfully reproduced the issue in AC's 2D Demo, by converting the Pause menu to a Unity UI one and using the PauseUI prefab provided in the AdventureCreator/UI/ folder and attaching the following simple script to its Panel GameObject.

private void OnEnable()
{
    Debug.Log("TestPauseUIPanel --- OnEnable");
}

void Start()
{
    Debug.Log("TestPauseUIPanel --- Start");
}

private void OnDisable()
{
    Debug.Log("TestPauseUIPanel --- OnDisable");
}

When I hit the Input Key to toggle the Menu, this is what happens in the Console:

This doesn't happen all the time, but surely it does when the Menu is turned on for the first time.

I found this out while trying to create a "navigable top bar" UI that:

• when enabled, turns on a default menu
• lets you switch between "tabs"
• when disabled, would also turn off whatever "tab" was on at the moment.

Am I doing anything wrong? I hope I provided enough information!

As always, thanks a lot in advance.

ChrisIceBox

There are times when AC needs to enable/disable a UI menu within a single frame - its initial spawning being one of them.

If you're trying to run code when a particular menu is being turned on/off, hook into the OnMenuTurnOn/Off events:

public Canvas canvas;

private void OnEnable ()
{
    EventManager.OnMenuTurnOn += OnMenuTurnOn;
    EventManager.OnMenuTurnOff += OnMenuTurnOff;
}

private void OnDisable ()
{
    EventManager.OnMenuTurnOn -= OnMenuTurnOn;
    EventManager.OnMenuTurnOff -= OnMenuTurnOff;
}

private void OnMenuTurnOn (AC.Menu menu, bool isInstant)
{
    if (menu.RuntimeCanvas == canvas)
    {
        // This menu was turned on
    }
}

private void OnMenuTurnOff (AC.Menu menu, bool isInstant)
{
    if (menu.RuntimeCanvas == canvas)
    {
        // This menu was turned off
    }
}

LostTrainDude

Thanks a lot, Chris! I'll convert my code to just use EventManager events.