Alloy - Possible to change event of button in different controller?

If I have a view defined like this:

<View>
    <View id="vwHeaderBar">
        <Button id="btnHeaderLeft" title="Back" onClick="act_btnHeaderLeft">
    </View>
    <View id="vwHeaderContent">
    </View>
</View>

Can I then change that onClick event for the button within another controller's view loaded into the vwHeaderContent view?

Most views I'll load into this just need the same action, which just closes the window. But one view I need it to do a few actions before the close.

I'd rather not have to define this button in each individual view, even if it's just for an exception case, since I don't want to have to manage the general layout in multiple places.

Is there a simple way of doing something like this?

I suppose I could loop over the children of my overall window until I find the button and try to override it that way, but if there is something obvious I'm missing, I'd appreciate a hint!