property tristate

This property sets or returns the tristate value of this box. This is used for boxes like checkboxes that may have a "in-between" state rather than just an on and off state.

function OnClickCheckButton()
{
    // Determine if checkbox is checked or not.
    var box = shell.currentEventTargetBox;
    if (box)
    {
        shell.print("Tristate = " + box.tristate);
        shell.print("Toggled = " + box.toggled);
    }
}