How to make newly added hotrect clickable?

[bobaer]

Hi there, I’ve been able to modify the stats_menu.xml to display the primary needs for Fallout 3 as meters like they do in F:NV.
I can mouseover them and they work great this way, but I would like to add the possibility to actually select them by clicking or by using the keyboard (the same way you can do it with the RAD button for example).
However, it seems to be not that easy to do that. Has someone experience with this kind of modding? Is there another XML file where you can define these buttons to be clickable or would you have to create a FOSE plugin to achieve this?

Anyway, I would be really thankful for any hints.

Here’s a screenshot you can hopefully see what I mean:

If it’s relevant for that matter, here’s the part of the XML code that represents the H2O (DUR) button:

			<hotrect name="stats_H2O_button">
				<id> 46 </id>
				<include src="super_text_box.xml"/>
				<string> <copy src="io" trait="_StatsH2OAbbrev" /> </string>
				<clicksound> UIMenuOK </clicksound>
				<mouseoversound> UIPipBoyHighlight </mouseoversound>
				<visible> <copy src="io" trait="_NeedsVisible" /> </visible>
				<_x> <copy src="sibling" trait="_x"/> </_x>
				<_y> <copy src="sibling" trait="_y"/> <add src="sibling" trait="height"/> </_y>
				<_fixedwidth> <copy src="sibling" trait="_fixedwidth"/> </_fixedwidth>
				<_horbuf> <copy src="sibling" trait="_horbuf"/> </_horbuf>
				<_verbuf> <copy src="sibling" trait="_verbuf"/> </_verbuf>
				<listindex> 4 </listindex>
				<_VUI+Emphasis>
					<copy src="child(VUI+Stat)" trait="alpha" />
					<sub> 255 </sub>
					<onlyif src="io" trait="_VUI+StatusInfo" />
				</_VUI+Emphasis>
				<text name="VUI+Stat">
					<_value> <copy src="io" trait="_H2O" /> <max> 0.1 </max> </_value>
					<string> <copy src="me" trait="_value" /> </string>
					<x> <copy src="parent" trait="x" /> <add src="parent" trait="width" /> <add> 10 </add> </x>
					<y> <copy src="parent" trait="_VUI+TextY" /> </y>
					<alpha>
						<copy> 255 </copy> <!--VUI+ disable brightness-based magnitude when _VUI+StatusInfo = 0 -->
						<onlyifnot src="io" trait="_VUI+StatusInfo" />
						<add>
							<copy src="me" trait="_value" /> <div> 3 </div> <add> 180 </add>
							<onlyif src="io" trait="_VUI+StatusInfo" />
						</add>
					</alpha>
					<brightness> <copy src="me" trait="alpha" /> </brightness>
					<visible> <not src="stats_effects_container" trait="visible"/> </visible> <!--VUI+ Vicious Wastes stats must always be visible because I can't do keyboard nav on them -->
					<font> <copy src="io" trait="font" /> </font>
				</text>
			</hotrect>

Thanks!

Edited May 9 by bobaer
clarification