ESO Lua File v100011

libraries/utility/zo_callbackobject.lua

[◄ back to folders ]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
ZO_CallbackObject = ZO_Object:Subclass()
function ZO_CallbackObject:New()
    local newObject = ZO_Object.New(self)
    newObject.fireCallbackDepth = 0
    newObject.dirtyEvents = {}
    return newObject
end
local CALLBACK_INDEX = 1
local ARGUMENT_INDEX = 2
local DELETED_INDEX = 3
--Registers a callback to be executed when eventName is triggered.
--You may optionally specify an argument to be passed to the callback.
function ZO_CallbackObject:RegisterCallback(eventName, callback, arg)    
    if(not eventName or not callback) then
        return
    end
    
    --if this is the first callback then create the registry
    if(not self.callbackRegistry) then
        self.callbackRegistry = {}
    end
    
    --create a list to hold callbacks of this type if it doesn't exist
    local registry = self.callbackRegistry[eventName]
    if(not registry) then
        registry = {}
        self.callbackRegistry[eventName] = registry
    end
    
    --store the callback with an optional argument
    --note: the order of the arguments to the table constructor must match the order of the *_INDEX locals above
    table.insert(registry, {callback, arg, false})    
end
function ZO_CallbackObject:UnregisterCallback(eventName, callback)    
    if(not self.callbackRegistry) then
        return
    end
    
    local registry = self.callbackRegistry[eventName]
    
    if(registry) then
        --find the entry
        for i = 1,#registry do
            local callbackInfo = registry[i]
            if(callbackInfo[CALLBACK_INDEX] == callback) then
                callbackInfo[DELETED_INDEX] = true
                self:Clean(eventName)
                return
            end
        end
    end    
end
function ZO_CallbackObject:UnregisterAllCallbacks(eventName)
    if(not self.callbackRegistry) then
        return
    end
    
    local registry = self.callbackRegistry[eventName]
    
    if(registry) then
        --find the entry
        for i = 1,#registry do
            local callbackInfo = registry[i]
            callbackInfo[DELETED_INDEX] = true
        end
        self:Clean(eventName)
    end    
end
--Executes all callbacks registered on this object with this event name
--Accepts the event name, and a list of arguments to be passed to the callbacks
--The return value is from the callbacks, the most recently registered non-nil non-false callback return value is returned
function ZO_CallbackObject:FireCallbacks(eventName, ...)
    local result = nil
    
    if(not self.callbackRegistry or not eventName) then
        return result
    end
    
    local registry = self.callbackRegistry[eventName]
    if(registry) then    
        self.fireCallbackDepth = self.fireCallbackDepth + 1
        local callbackInfoIndex = 1
        while callbackInfoIndex <= #registry do
            --pass the arg as the first parameter if it exists
            local callbackInfo = registry[callbackInfoIndex]
            local argument = callbackInfo[ARGUMENT_INDEX]
            local callback = callbackInfo[CALLBACK_INDEX]
            local deleted = callbackInfo[DELETED_INDEX]
            
            if(not deleted) then
                if(argument) then
                    result = callback(argument, ...) or result
                else
                    result = callback(...) or result
                end
            end
            callbackInfoIndex = callbackInfoIndex + 1
        end
        self.fireCallbackDepth = self.fireCallbackDepth - 1
        self:Clean()
    end
    
    return result
end
function ZO_CallbackObject:Clean(eventName)
    if(eventName) then
        self.dirtyEvents[#self.dirtyEvents + 1] = eventName
    end
    if(self.fireCallbackDepth == 0) then
        while #self.dirtyEvents > 0 do
            local eventName = self.dirtyEvents[#self.dirtyEvents]
            local registry = self.callbackRegistry[eventName]
            if(registry) then    
                local callbackInfoIndex = 1
                while callbackInfoIndex <= #registry do
                    local callbackTable = registry[callbackInfoIndex]
                    if(callbackTable[DELETED_INDEX]) then
                        table.remove(registry, callbackInfoIndex)
                    else
                        callbackInfoIndex = callbackInfoIndex + 1
                    end
                end
                if(#registry == 0) then
                    self.callbackRegistry[eventName] = nil
                end
            end
            self.dirtyEvents[#self.dirtyEvents] = nil
        end
    end
end