There is nothing to share. There is no need to "find" anything. Buttons cannot be "active" or "normal". They can have the input focus or not.
Perhaps you mean the "checked" state of control. The behavior you described corresponds to the set of
radio buttons, not "regular" buttons:
http://www.w3.org/TR/html-markup/input.radio.html[
^].
<form ...>
<input type="radio" value="1">1 Day</input>
<input type="radio" value="5">5 Days</input>
<!--
<input type="radio" value="max" checked="checked">Max</input>
</form>
—SA