TriggerEvent: Difference between revisions

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===Returns===
===Returns===
* Returns '''nil''' if the arguments are invalid or the event could not be found.   
* Returns '''nil''' if the arguments are invalid or the event could not be found.   
* Returns '''true''' if the event was triggered successfully, and was not cancelled using [[cancelEvent]].
* Returns '''true''' if the event was triggered successfully, and ''was not'' cancelled using [[cancelEvent]].
* Returns '''false''' if the event was triggered successfully, and was successfully cancelled using [[cancelEvent]].
* Returns '''false''' if the event was triggered successfully, and ''was'' cancelled using [[cancelEvent]].


==Example==  
==Example==  

Revision as of 23:02, 6 December 2007

This function will trigger a named event on a specific element in the element tree. See event system for more information on how the event system works.

You should avoid triggering events on the root element unless you really need to. Doing this triggers the event on every element in the element tree, which is potentially very CPU intensive. Use as specific (i.e. low down the tree) element as you can.

Syntax

bool triggerEvent ( string eventName, element baseElement, [ var argument1, ... ] )    

Required Arguments

  • eventName: The name of the event you wish to trigger
  • baseElement: The element you wish to trigger the event on. See event system for information on how this works.

Optional Arguments

NOTE: When using optional arguments, you might need to supply all arguments before the one you wish to use. For more information on optional arguments, see optional arguments.

  • argument1: The first argument that the event handler expects should be added after the baseElement variable.
    • NOTE: This function can have more than one of these arguments specified, once for each argument the event handler is expecting.

Returns

  • Returns nil if the arguments are invalid or the event could not be found.
  • Returns true if the event was triggered successfully, and was not cancelled using cancelEvent.
  • Returns false if the event was triggered successfully, and was cancelled using cancelEvent.

Example

If you define a new custom event as follows:

-- Get the root map element
rootElement = getRootElement ()

-- Add a new event called onSpecialEvent
addEvent ( "onSpecialEvent", "text" )
-- Define our handler function
function specialEventHandler ( text )
	outputChatBox ( text )
end
-- Add the event handler
addEventHandler ( "onSpecialEvent", rootElement, specialEventHandler )

You can then trigger this event later on using:

triggerEvent ( "onSpecialEvent", rootElement, "test" )

See Also