Open topic with navigation

onParameterChange

This callback function gets called whenever a user changes one of the previously added parameter values.

Syntax

onParameterChange(parameterName, parameterValue);

Parameters

parameterName

String value representing the name of the parameter.

parameterValue

String value representing the newly modified value for the parameter.

Remarks

If a study is relying on certain parameters to calculate its values, this method could update study's internal memory variables with newly modified parameter values at the time when they are changed.

For example, this callback is very handy when a study is utilizing setMinRequiredDataValues() method to keep the minimum number of available source data points, and when a particular parameter is tied to that minRequiredDataValue number. See example below:

Example

The following example demonstrates the use of onParameterChange() callback function.

function init()

{

//add parameter "Period" and set it to default value of 10

this.addParameter("Period", 10);

//get the value for parameter "Period", and use that value to indicate the minimum required data value

this.setMinRequiredDataValues(parseInt(getParameter("Period")));

}

function onParameterChange(parameterName, parameterValue)

{

//if parameterName is "Period", then update minimum required data value

if(parameterName == "Period")

this.setMinRequiredDataValues(parseInt(parameterValue));

} 

See Also

setMinRequiredDataValues(), addParameter()

Copyright © 2006-2009 ActiveTick LLC