extend UI5 component "onChange" for a Lumira SDK

[hasba]

Hello,

i've searched a lot but couldn't find a solution to my question. i have this standard component:

sap.m.FormattedText

this has no event when the property htmlText has changed.

how can i extend this to have the possibility to react to the changes done i.e. via the function setHtmlText.

i have added one property in the contribution.xml

<property
			id="htmlText"
			title="HTML Text"
			tooltip="Text with placeholders"
			type="String"
			bindable="true"/>

<property id="onHTMLChanged" type="ScriptText" title="On Changed" group="Events" />

What do i have to code in order to use the 2 Functions fireDesignStudioPropertiesChanged and fireDesignStudioEvent?

define([], function() {
	sap.m.FormattedText.extend("com.xxx.formattedtext.Formattedtext", {

		initDesignStudio: function() {


        this.fireDesignStudioPropertiesChanged(["htmlText"]);

        this.fireDesignStudioEvent("onHTMLChanged");