Type Function Library timer.* Return value Table Revision Release 2022.3683 Keywords timer, delay, performWithDelay See also timer timer.pause() timer.cancel()
Calls a specified function after a delay. This function returns a table that can be used with other timer functions. For example, the returned table can be passed to timer.cancel() to cancel the invocation of the specified listener.
Timers will be automatically paused when the application is suspended and resume when the application is resumed. However, to avoid unwanted behaviours, it is strongly advised to handle your timers manually. Thus, if you have running timers that are not paused and resumed (in code) upon suspension of the app, you should handle this task by calling timer.pause() and timer.resume() on all applicable timers.
Timers will not be automatically cancelled when changing a scene. Thus, if you have running timers that are not cancelled, you must handle this manually by calling timer.cancel() on all applicable timers.
timer.performWithDelay( delay, listener [, iterations] [, tag] )
Number. The delay in milliseconds, for example, 1000
= 1 second. Note that timers cannot execute faster than the runtime framerate of the app. For example, if the framerate of the app is 60
frames per second, as defined in the config.lua
file (guide), the shortest delay for a timer is approximately 16.667
milliseconds 1000
/60
= ~16.667
)
Listener. The listener to invoke after the delay. This may be either a function listener or a table listener. If a table listener, it must have a timer method because timer events are sent to the listener.
Number. Optionally specify the number of times listener
is to be invoked. By default, it is 1
; pass 0
or -1
if you want the timer to loop forever.
String. Optionally assign a tag
to the timer. You can pause, resume or cancel all timers that share the same tag
with a single function call. Note: Using tag
requires Solar2D 2020.3611
or a newer build.
local function listener( event ) print( "listener called" ) end timer.performWithDelay( 1000, listener )
local listener = {} function listener:timer( event ) print( "listener called" ) end timer.performWithDelay( 1000, listener )
-- Lua closure method local function spawnBall( randomPosition ) ballPosition = display.newCircle( 100, 100, 20 ) ballPosition.x = randomPosition end -- Obtain a random number for the spawned object's x position local randomPosition = 100 + math.random(200) -- Wrap "spawnBall" and "randomPosition" inside a closure local myClosure = function() return spawnBall( randomPosition ) end timer.performWithDelay( 2000, myClosure, 1 )
-- Variable handle method local function onTimer( event ) -- Access "params" table by pointing to "event.source" (the timer handle) local params = event.source.params print( params.myParam1 ) print( params.myParam2 ) end -- Assign the timer to a variable "tm" local tm = timer.performWithDelay( 1000, onTimer ) -- Assign a table of parameters to the "tm" handle tm.params = { myParam1 = "Parameter1", myParam2 = "Parameter2" }
If you want to add new functionality or modify existing ones, you can download or fork the source code from GitHub and include in your project(See Using External Modules).