Mr millchick: Created page with "Category:Lua '''function''' createTimer(''owner'' OPTIONAL, ''enabled'' OPTIONAL) : '''Timer''' '''function''' createTimer(''interval'', ''callback'', ''...'' OPTIONAL) :..."

2025-10-25T05:12:37Z

Created page with "Category:Lua '''function''' createTimer(''owner'' OPTIONAL, ''enabled'' OPTIONAL) : '''Timer''' '''function''' createTimer(''interval'', ''callback'', ''...'' OPTIONAL) :..."

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[[Category:Lua]]
'''function''' createTimer(''owner'' OPTIONAL, ''enabled'' OPTIONAL) : '''Timer'''

'''function''' createTimer(''interval'', ''callback'', ''...'' OPTIONAL) : '''Timer'''

Creates a [[Lua:Class:Timer|Timer]] object that fires repeatedly or once at specified intervals.

* '''Returns:''' A [[Lua:Class:Timer|Timer]] UserData object
* '''Modes:''' Two distinct calling modes with different behaviors

== Two Calling Modes ==

'''Mode 1: Persistent Timer''' - Creates a recurring timer that continues until destroyed or disabled
createTimer(owner, enabled)

'''Mode 2: One-Shot Timer''' - Creates a timer that fires once and auto-destroys
createTimer(interval, callback, ...)

== Function Parameters ==

=== Mode 1: Persistent Timer ===

{|width="85%" cellpadding="10%" cellpadding="5%" cellspacing="0" border="0"
!align="left"|Parameter
!align="left"|Type
!style="width: 80%;" align="left"|Description
|-
|owner
|Component or nil
|'''Optional.''' Parent component that owns this timer. When the owner is destroyed, the timer is destroyed too. Pass '''nil''' or omit for standalone timer. Default: '''nil'''
|-
|enabled
|boolean
|'''Optional.''' Whether the timer starts active immediately. Default: '''true'''
|}

=== Mode 2: One-Shot Timer ===

{|width="85%" cellpadding="10%" cellpadding="5%" cellspacing="0" border="0"
!align="left"|Parameter
!align="left"|Type
!style="width: 80%;" align="left"|Description
|-
|interval
|integer
|Timer delay in '''milliseconds''' before callback fires once
|-
|callback
|function
|Function to execute when the timer fires. Receives any additional varargs as parameters
|-
|...
|'''varargs'''
|'''Optional.''' Additional arguments to pass to the callback function
|}

== Usage Examples ==

=== Persistent Timer Examples ===

'''Basic recurring timer (runs every second):'''
local timer = createTimer()
timer.Interval = 1000 -- 1 second
timer.OnTimer = function()
print("Tick: " .. os.date("%H:%M:%S"))
end

'''Timer with owner (destroyed when form closes):'''
local form = createForm()
local timer = createTimer(form)
timer.Interval = 500
timer.OnTimer = function()
form.Caption = "Time: " .. os.date("%H:%M:%S")
end

'''Timer owned by main form (auto-cleanup when CE closes):'''
local timer = createTimer(getMainForm())
timer.Interval = 1000
timer.OnTimer = function()
print("Running until CE closes")
end

'''Create disabled timer and enable later:'''
local timer = createTimer(nil, false)
timer.Interval = 2000
timer.OnTimer = function()
print("2 seconds passed")
end
-- Enable when needed
timer.Enabled = true

'''Manual cleanup when done:'''
local timer = createTimer()
timer.Interval = 100
local count = 0
timer.OnTimer = function()
count = count + 1
print("Count: " .. count)
if count >= 10 then
timer.Enabled = false
timer.destroy()
print("Timer stopped and destroyed")
end
end

'''Toggle timer on/off:'''
local timer = createTimer()
timer.Interval = 1000
timer.Enabled = false
timer.OnTimer = function()
print("Active!")
end

-- Start
timer.Enabled = true
-- Stop
timer.Enabled = false

=== One-Shot Timer Examples ===

'''Simple delay (auto-destroys after firing):'''
createTimer(2000, function()
print("Executed after 2 seconds")
end)

'''One-shot timer with parameters:'''
local name = "Player"
local health = 100

createTimer(1500, function(playerName, hp)
print(playerName .. " health: " .. hp)
end, name, health)

'''Delayed execution in sequence:'''
print("Starting...")
createTimer(1000, function()
print("Step 1: After 1 second")
end)
createTimer(2000, function()
print("Step 2: After 2 seconds")
end)
createTimer(3000, function()
print("Step 3: After 3 seconds")
end)

'''One-shot timer with closure:'''
local function showMessage(msg)
createTimer(1000, function()
print("Delayed message: " .. msg)
end)
end

showMessage("Hello World")

'''Delayed form update:'''
local form = createForm()
form.Caption = "Loading..."

createTimer(2000, function()
form.Caption = "Ready!"
end)

=== Advanced Timer Patterns ===

'''Countdown timer:'''
local countdown = 10
local timer = createTimer()
timer.Interval = 1000
timer.OnTimer = function()
print("Countdown: " .. countdown)
countdown = countdown - 1
if countdown < 0 then
timer.Enabled = false
timer.destroy()
print("Countdown complete!")
end
end

'''Periodic memory check:'''
local timer = createTimer()
timer.Interval = 500
timer.OnTimer = function()
local addr = getAddress("player.health")
if addr then
local health = readInteger(addr)
if health < 50 then
print("Warning: Low health!")
end
end
end

'''Auto-refresh display:'''
local form = createForm()
local label = createLabel(form)
label.Caption = ""

local timer = createTimer(form)
timer.Interval = 100
timer.OnTimer = function()
local addr = getAddress("game.score")
if addr then
label.Caption = "Score: " .. readInteger(addr)
end
end

'''Rate-limited action:'''
local canExecute = true
local timer = createTimer(nil, false)
timer.Interval = 1000
timer.OnTimer = function()
canExecute = true
timer.Enabled = false
end

function performAction()
if canExecute then
print("Action executed!")
canExecute = false
timer.Enabled = true
else
print("Please wait...")
end
end

== Persistent vs One-Shot Comparison ==

{|width="85%" cellpadding="5%" cellspacing="0" border="1"
!style="width: 30%;" align="left"|Feature
!align="left"|Persistent Timer
!align="left"|One-Shot Timer
|-
|'''Creation'''
|createTimer() or createTimer(owner, enabled)
|createTimer(interval, callback, ...)
|-
|'''Behavior'''
|Fires repeatedly until disabled
|Fires once and auto-destroys
|-
|'''Cleanup'''
|Must call destroy() manually
|Destroys itself automatically
|-
|'''Control'''
|Can enable/disable with .Enabled
|Cannot control after creation
|-
|'''Callback Setup'''
|Set .OnTimer property after creation
|Callback passed during creation
|-
|'''Typical Use'''
|Monitoring, periodic updates, UI refresh
|Delays, deferred execution, timeouts
|}

== Notes ==

* '''Interval''' is in milliseconds (1000 = 1 second)
* Timers inherit from [[Lua:Class:Component|Component]] class
* '''One-shot timers''' automatically free themselves - do not call destroy()
* '''Persistent timers''' must be destroyed manually or by owner
* Use '''getMainForm()''' as owner to auto-destroy timer when CE closes
* Timer callbacks execute in the main CE thread
* Setting '''Enabled = false''' pauses the timer without destroying it
* Timer accuracy depends on system load (~15ms resolution on Windows)

== Common Mistakes ==

'''Don't store one-shot timer reference:'''
-- WRONG: One-shot timer will self-destruct
local t = createTimer(1000, function() print("Hi") end)
-- t becomes invalid after firing

-- RIGHT: Just create and forget
createTimer(1000, function() print("Hi") end)

'''Don't forget to destroy persistent timers:'''
-- WRONG: Memory leak if timer never destroyed
function startMonitoring()
local t = createTimer()
t.Interval = 1000
t.OnTimer = function() print("Check") end
end

-- RIGHT: Store reference and destroy when done
local monitorTimer = nil
function startMonitoring()
monitorTimer = createTimer()
monitorTimer.Interval = 1000
monitorTimer.OnTimer = function() print("Check") end
end
function stopMonitoring()
if monitorTimer then
monitorTimer.destroy()
monitorTimer = nil
end
end

{{LuaSeeAlso}}

=== Related Functions ===
* [[Lua:sleep|sleep]] - Blocking delay alternative
* [[Lua:createThread|createThread]] - Non-blocking threading

=== Related Classes ===
* [[Lua:Class:Timer|Timer]] - Timer class documentation
* [[Lua:Class:Component|Component]] - Base class for Timer

Lua:createTimer - Revision history

Mr millchick: Created page with "Category:Lua '''function''' createTimer(''owner'' OPTIONAL, ''enabled'' OPTIONAL) : '''Timer''' '''function''' createTimer(''interval'', ''callback'', ''...'' OPTIONAL) :..."