function position_calculate(element)
{
    var valueT = 0, valueL = 0;
    do {
        valueT += element.offsetTop  || 0;
        valueL += element.offsetLeft || 0;
        element = element.offsetParent;
    } while (element);
    return [valueL, valueT];
}

function previewON(contents,content_obj,obj,topmargin,leftmargin)
{
    var pos = position_calculate(obj);
    var previewpanel = document.getElementById(content_obj);
    var plefT = pos[0]-topmargin;
    var ptoP = (pos[1]+17)-leftmargin;
    previewpanel.innerHTML = contents;
    previewpanel.style.left = plefT +'px';
    previewpanel.style.top =  ptoP + 'px';
    previewpanel.style.display = 'block';
}

function previewOFF(content_obj)
{
    var previewpanel = document.getElementById(content_obj);
    previewpanel.style.display = 'none';
}