Issue with multiple mods replacing delegates of buttons

[linuxgurugamer]

I ran into this problem a month ago, and first spent several hours isolating it down to two specific mods, and then today I spent a number of hours debugging it.  What made it strange was that the two mods both worked perfectly by themselves, it was only when both were installed that the problem showed up.

It was very strange., you can read about the issue here: 

 

The problem of multiple buttons when both Fill-It-Up and Progressive-Colonization are present (and most likely Werner's Checker as well) arises because both mods are replacing the listener of the EditorLogic.fetch.launchBtn.onClick.  Then, when the button is clicked, BOTH replacements are called, 
and then both of them are invoking the EditorLogic.fetch.launchVessel

This isn't a bug in either mod, it's a bug in the implementation since there is no way for a mod to get a delegate of a button which is an unknown method.

While it's possible to remove all listeners, the only one this would work for would be the last mod initialized, since it would remove all others.

Ideally, what should happen is one of the following (for the purposes of this discussion, I'll refer to both mods via abbreviations, and also assume there are only two mods, but this applies to any number of mods):

1. The new UnityAction which each mod adds would be called simultaneously, and then only when both have finished, the original delegate (EditorLogic.fetch.launchVessel) would be called.
2. The first mod initialized would be called first, and when it was done the second mod would be called, and finally the original delegate would be called.
3. A mod will specify a priority when initializing .

This can't be solved by one mod, a solution needs to be implemented and used by all mods which replaces the delegate(s) of this button.

I am working on a solution for this because:

1. I found the problem
2. I have at least two mods affected by this problem

I'm writing a tiny mod which will be used by any other mod to control access to this button and it's delegates:

class ButtonManager
{
    void InitializeListener(UnityEngine.UI.Button button,  UnityAction delegate);
    int AddListener(UnityEngine.UI.Button button,  UnityAction delegate, int priority = 5);
    void RemoveListener(UnityEngine.UI.Button button,  UnityAction delegate);
    void RemoveListener(int listenerId);

    int GetListenerCount(UnityEngine.UI.Button button);
    void RemoveAllListeners(UnityEngine.UI.Button button);

    void InvokeNextDelegate(int currentDelegateId);

    void SetModeSequential();
    void SetModeSimultaneous();
}

The priority will be used to determine the order of listeners to be called.  Higher priorities will be run first.  For the Sequential mode, mods with the same priority will be run in the order initialized.

 

InitializeListener	Initializes the mod to work with the specified button.  The delegate should be the same as what the default it, it will have the lowest priority
AddListener	Adds a delegate to a button with a specified priority.  Returns a listenerId, used below
RemoveListener	Removes a delegate from a button
GetListenerCount	Gets a count of all the listeners
RemoveAllListeners	Removes all except the default listener
InvokeNextDelegate	Tells the mod to call the next delegate on the list
SetModeSequential   SetModeSimultaneous	These two can set or change the mode, sequential will run one delegate at a time, simultaneous will run all of the same priority at the same time, and then the next lower, etc

 

 

 

 

 

 

 

 

 

I hope to have this finished in the next few days, and will first implement it in my mods.

Edited June 6, 2020 by linuxgurugamer