var openDivs = [];
function toggleDiv ( id, level ) {
    var div = document.getElementById( id );
    if ( div.style.display == "block" )
        div.style.display = "none";
    else {
        if ( openDivs[level] ) openDivs[ level ].style.display = "none";
        openDivs[ level || 0 ] = div;
        div.style.display = "block";
    }
}
function toggleAll ( checkbox, id ) {
    var divs = document.getElementById( "containerDiv" 
).getElementsByTagName( "div" );
    var display = checkbox.checked ? "block" : "none";
    for ( var i=0; i < divs.length; i++ )
        divs[ i ].style.display = display; }