Key Listener

Welcome to the svyKeyListener wiki!

Introduction

svyKeyListener is a simple service to send key strokes from the browser to a callback method executing on the server This allows a developer to handle keystroke events inside the servoy environment. "keylistener" attribute of a component (from Properties view) must be used together with addKeyListener API of the service to get desired effect.

Table of contents

• svyKeyListener API

svyKeyListener API

Method	Params	Return	Description
addKeyListener	callbackKey:string, callback:Function, [clearPreviousCallback:boolean], [delay:boolean], [regexPattern:boolean], [regexReplacement:boolean]		Registers the listener on the components which have the "keylistener" attribute with the given callbackKey value, to call the given callback
removeKeyListener	callbackKey:string	boolean	Removes the listener associated to the given callback key

addKeyListener

Registers the listener on the components which have the "keylistener" attribute with the given callbackKey value, to call the given callback. Params

Type	Name	Description	Required
string	callbackKey	The callback key.	Required
Function	callback	The function will be called and passed [string value, JSEvent event, number keyCode, boolean altKey, boolean ctrlKey, boolean shiftKey, boolean capsLock]	Required
boolean	clearCB	Specifies if the previously added callback associated to this callback key should be removed.	Optional
int	delay	Debouncing for callback function. The callback is fired only when the specified delay (milliseconds) has been pass. If "delay" is not specified, a default delay of 1000 ms will be used."	Optional
String	regexPattern	Javascript regular expression string to modify current value of the component	Optional
String	regexReplacement	The value that is used to replace the regular expression with in the current value of the component	Optional

Returns void

example

On the component(s) you want to register the listener, you need to add a keylistener attribute. Let's assume we add the keylistener attribute with the value test to be used as a callback key:

keylistener attribute

Then, for instance in the onShow method of the form, you need to associate that callback key to a function:

function onShow(firstShow, event) {
	plugins.keyListener.addKeyListener('test', onKey)
}

function onKey(value, event, keyCode, altKey, ctrlKey, shiftKey, capsLock){
        application.output("The new value is "+value);
}

The behavior may be altered using optional parameters:

function onShow(firstShow, event) {
        // the onKey() will be triggered after 500 ms. The 'blue' string from the input value will be 
        // replaced with 'red' string.
	plugins.keyListener.addKeyListener('test', onKey, false, 500, 'blue', 'red');
}

function onKey(value, event, keyCode, altKey, ctrlKey, shiftKey, capsLock){
        application.output("The new value is "+value);
}

removeKeyListener

Removes the listener associated to the given callback key. Returns true if the listener was removed.

Params

Type	Name	Description	Required
string	callbackKey	The callback key.	Required

Returns boolean

example

function onAction(event) {
	if (plugins.keyListener.removeKeyListener('test')) {
           application.output("Removed the key listener associated to the callback key 'test'");
        }
}