LoTROInterface - Using Add/Remove callback functions with the localplayer EffectList

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Using Add/Remove callback functions with the localplayer EffectList

I'm working/updating my simple Party Debuff Tracker plugin, and I'm trying to get it to remove the local players "EffectAdded" event from the EffectList. For whatever reason, it does not work, yet will work for all other members of a players fellowship. Here is some relevant code:

Code:

-- player is the current member of the fellowship we are creating events for (loop is in another function)

function EffectTracker:HandleEffects(player)

        self.effectList[player:GetName()] = player:GetEffects(); -- kept for removecallback function

        self.effectAddedHandler = function(sender, args)

                -- outputs data to chat window (code not important to discussion)

        end

        AddCallback(player:GetEffects(), "EffectAdded", self.effectAddedHandler);

end



-- used to make sure party is current

function EffectTracker:UpdateParty()

        self.partyChangedHandler = function(sender, args)

                if localPlayer:GetParty() == nil then

                        RemoveCallback(party, "MemberAdded", self.partyChangedHandler);

                        RemoveCallback(party, "MemberRemoved", self.partyChangedHandler);

                        self:RemoveEffectCallbacks();

                end

                party = localPlayer:GetParty();

                self:TrackEffects();

        end

        AddCallback(localPlayer, "PartyChanged", self.partyChangedHandler);

        AddCallback(localPlayer, "RaidChanged", self.partyChangedHandler);

        if party ~= nil then

                self:TrackEffects();

        end

end



-- this is where the problem is

function EffectTracker:RemoveEffectCallbacks()

        if self.effectList ~= nil then

                for k, v in pairs(self.effectList) do

                -- should remove event functions for the EffectAdded events for all members of the fellowship. It works for every member of the fellowship, but fails to remove the localplayers event.

                        RemoveCallback(v, "EffectAdded", self.effectAddedHandler);

                end

                -- added this to remove that callback that is not removed using RemoveCallback() function

                if localPlayer:GetEffects()["EffectAdded"] ~= nil then

                        localPlayer:GetEffects()["EffectAdded"] = nil;

                end

        end

end

When I added some chat output lines to the RemoveCallback() function, it seems that "if object[event] == callback then" isn't "working" correctly for the EffectList of the local player. I cannot tell why, as the EffectList for other party members works correctly. It seems the table that holds the EffectList changes somewhat from setting the event function to removing it so the "object[event]" points somewhere else, however, the object[event] isn't nil, but I'm not quite sure how to check what exactly it is holding (apparently not the self.effectAddedHandler function). Considering that my workaround won't play safe with other plugins or other EffectAdded events to the local player, this is a somewhat annoying problem. Perhaps I am just missing something but I can't see it right now. If you need clarification please let me know. Thanks for your help!

Just a quick glance shows that you are redefining the self.effectAddedHandler function on every call to EffectTracker:HandleEffects so the table representing the function is not the same after each call. The function should either be defined once and used for everyone or there should be a table of functions with one instance for each player depending on what exactly you are doing with the function. But in any case you definately should not be redefining the function and then expecting it to match when you remove it - in other words, only functions that match an entry in the event table will get removed and since you redefined it, it doesn't match and isn't removed. As implemented, this actually should fail for all but one party member, that being the last one passed to EffectTracker:HandleEffects so I'm not sure how you were testing but if you only tested with a party of two then it would appeared to be working for all but the local player (when in fact it was just working for the last one added).

Basically, to fix this, move the definition of the callback funtions outside of the routine that adds them (you would use the "sender" argument to determine which player triggered the event) or create a table of functions, one for each player, i.e. self.effectAddedHandler[player:GetName()]=function...
Of couse, if you go the route of using a table, then you have to pass the correct instance to the removecallback -
RemoveCallback(v, "EffectAdded", self.effectAddedHandler[k]);

So, option 1 is to move the definition outside :HandleEffects and use the Sender to determine the player that fired the event

Code:

self.effectAddedHandler = function(sender, args)

 -- outputs data to chat window (code not important to discussion)

end

function EffectTracker:HandleEffects(player)

 self.effectList[player:GetName()] = player:GetEffects(); -- kept for removecallback function

 AddCallback(player:GetEffects(), "EffectAdded", self.effectAddedHandler);

end

-- used to make sure party is current

self.partyChangedHandler = function(sender, args)

 if localPlayer:GetParty() == nil then

  RemoveCallback(party, "MemberAdded", self.partyChangedHandler);

  RemoveCallback(party, "MemberRemoved", self.partyChangedHandler);

  self:RemoveEffectCallbacks();

 end

 party = localPlayer:GetParty();

 self:TrackEffects();

end

function EffectTracker:UpdateParty()

 AddCallback(localPlayer, "PartyChanged", self.partyChangedHandler);

 AddCallback(localPlayer, "RaidChanged", self.partyChangedHandler);

 if party ~= nil then

  self:TrackEffects();

 end

end

-- this is where the problem is

function EffectTracker:RemoveEffectCallbacks()

 if self.effectList ~= nil then

  for k, v in pairs(self.effectList) do

                -- should remove event functions for the EffectAdded events for all members of the fellowship. It works for every member of the fellowship, but fails to remove the localplayers event.

  RemoveCallback(v, "EffectAdded", self.effectAddedHandler);

  end

                -- added this to remove that callback that is not removed using RemoveCallback() function

  if localPlayer:GetEffects()["EffectAdded"] ~= nil then

  localPlayer:GetEffects()["EffectAdded"] = nil;

  end

 end

end

and option 2 is to use a table of handlers

Code:

self.effectAddedHandler={}

function EffectTracker:HandleEffects(player)

 local playerName=player:GetName()

 self.effectList[playerName] = player:GetEffects(); -- kept for removecallback function

 self.effectAddedHandler[playerName] = function(sender, args)

  -- outputs data to chat window (code not important to discussion)

 end

 AddCallback(player:GetEffects(), "EffectAdded", self.effectAddedHandler[playerName]);

end

-- used to make sure party is current

self.partyChangedHandler = function(sender, args)

 if localPlayer:GetParty() == nil then

  RemoveCallback(party, "MemberAdded", self.partyChangedHandler);

  RemoveCallback(party, "MemberRemoved", self.partyChangedHandler);

  self:RemoveEffectCallbacks();

 end

 party = localPlayer:GetParty();

 self:TrackEffects();

end

function EffectTracker:UpdateParty()

 AddCallback(localPlayer, "PartyChanged", self.partyChangedHandler);

 AddCallback(localPlayer, "RaidChanged", self.partyChangedHandler);

 if party ~= nil then

  self:TrackEffects();

 end

end

-- this is where the problem is

function EffectTracker:RemoveEffectCallbacks()

 if self.effectList ~= nil then

  for k, v in pairs(self.effectList) do

                -- should remove event functions for the EffectAdded events for all members of the fellowship. It works for every member of the fellowship, but fails to remove the localplayers event.

  RemoveCallback(v, "EffectAdded", self.effectAddedHandler[k]);

  end

                -- added this to remove that callback that is not removed using RemoveCallback() function

  if localPlayer:GetEffects()["EffectAdded"] ~= nil then

  localPlayer:GetEffects()["EffectAdded"] = nil;

  end

 end

end

As I first mentioned, this was just a quick glance so there may be other issues but this was the first that I noticed and seemed to cause the symptom you were experiencing. I also didn't test the solution code so there may be typos but the intent should be clear.

Yeah I was only testing with 2 players since it's the easiest way to do it.

And option one is what I was going for. I knew I was overlooking something like that, which is why I posted the question. I miss having a roommate that knows coding because this stuff is solved a lot faster!

Thanks Garan!

Edit: The sender in that event call is the EffectList that calls the event, not the player. How would I go about getting the player that the EffectList is for? Can I add a third parameter to the self.effectAddedHandler to be the player that has the EffectList, or would I have to go with option 2 and use the table?

Quote:

Originally Posted by Stever1388 (Post 8581)

You could add a .Player value to the self.effectList[] table entries to create a link back to the player:
change EffectTracker:HandleEffects to

Code:

function EffectTracker:HandleEffects(player)

 self.effectList[player:GetName()] = player:GetEffects(); -- kept for removecallback function

 self.effectList[player:GetName()].Player=player; -- creates a link back to the player

 AddCallback(player:GetEffects(), "EffectAdded", self.effectAddedHandler);

end

and then in effectAddedHandler you could use sender.Player

Code:

self.effectAddedHandler = function(sender, args)

 -- outputs data to chat window (code not important to discussion)

  --sender.Player references the player for this effect list

end

Thanks for your help. The second option isn't really that tough to implement anyway, so I went ahead with that.

Quote:

Originally Posted by Garan (Post 8582)

You could add a .Player value to the self.effectList[] table entries to create a link back to the player:
change EffectTracker:HandleEffects to

Code:

function EffectTracker:HandleEffects(player)

 self.effectList[player:GetName()] = player:GetEffects(); -- kept for removecallback function

 self.effectList[player:GetName()].Player=player; -- creates a link back to the player

 AddCallback(player:GetEffects(), "EffectAdded", self.effectAddedHandler);

end

and then in effectAddedHandler you could use sender.Player

Code:

self.effectAddedHandler = function(sender, args)

 -- outputs data to chat window (code not important to discussion)

  --sender.Player references the player for this effect list

end

This is an interesting way to do it too. Any real advantage to doing it either way?

Quote:

Originally Posted by Stever1388 (Post 8584)

This is an interesting way to do it too. Any real advantage to doing it either way?

Well, fewer function definitions means a slightly smaller memory footprint but in this case that seems pretty minor. Of course, adding a property to a Turbine generated table runs a minor risk of conflicting with a future Turbine property but that risk is nearly infinitesimal in this case. So, no, there isn't a clear advantage to either solution. I personally would probably use option 1 but that's more a matter of personal preference than actual advantage.