function cHelpScreen(){                 
    this.init = false;
    this.iPage = 0;
    this.fSpeed = 0.9;
        
    this.show = function(pagina_titel, help_tekst){     
    
        if ( !this.init ) {
            this.oBody = document.getElementsByTagName('body')[0];
            this.oHtml = document.getElementsByTagName('html')[0];  
            this.oContainer = document.getElementById('help_container');
            this.oContainer.style.display = "none";
            this.init = true;
        }
        
        try {                             
            oBody.style.overflow = 'hidden';
        } catch (e){ }
        try {
            oHtml.style.overflow = 'hidden';
        } catch (e){ } 
        
        this.oContainer.style.display = "";
        
        var aHtml = Array();

        this.createContainer(aHtml, 'top');
        
        //aHtml.push('<iframe frameborder="0" scrolling="no" src="' + sBaseUrl + 'GeoStart/help/helpFrame.php?sColor=' + sColor + '" width="579" height="508" ></iframe>');
        aHtml.push('<iframe frameborder="0" scrolling="no" src="http://dhggeo.02.swis.nl/GeoStart/help/helpContent.php?help_tekst=' + help_tekst + '&pagina_titel=' + pagina_titel + '" width="800" height="100" ></iframe>');

        
        this.createContainer(aHtml, 'bottom_custom');
                
        this.oContainer.innerHTML = aHtml.join('');
        
        resizer();              
    }  
           
   
    this.hide = function(){   
        if ( this.oContainer ) {       
            //this.oContainer.style.display = "none"; 
            document.getElementById('mailIframe').style.display = "none";   
            document.getElementById('help_draggable').style.display = "none";   
        }
    }
    
    this.createContainer = function(aHtml, sPart){    
        switch ( sPart ) {
            case 'top':   
//                aHtml.push('<div id="mailIframe" onclick="oHelp.hide();" style="z-index:99997;height:100%;width:100%;background:#555;filter: alpha(opacity=80);opacity: 0.8;position:absolute;top:0;left:0;"></div>');
                aHtml.push('<div id="mailIframe" onclick="oHelp.hide();"></div>');
                aHtml.push('    <div id="help_draggable">');
                aHtml.push('        <a onclick="oHelp.hide();return false;" style="position:absolute;right:8px;top:5px;text-decoration:none;color:#690e0e;cursor:pointer;"><img src="http://dhggeo.02.swis.nl/GeoStart/help/help_ballon/demoWindow_close.png" height="15" width="17"></a>');
                break;
            case 'bottom_custom':
                aHtml.push('</div>');                                           
                break                
            case 'bottom':            
                if ( readCookie('hideHelp') != 'true' ) {
                    var sChecked = " ";
                } else {
                    var sChecked = " checked=checked ";
                }
            
                aHtml.push('        <div id="footer" style="margin:0 10px ;">');
                aHtml.push('            <label for="setcookie" style="vertifcal-align:middle;">');
                aHtml.push('                <input ' + sChecked + ' onchange="cookieHandler();" id="setcookie" type="checkbox" style="vertical-align:middle;"/>');
                aHtml.push('                Dit venster niet meer tonen');
                aHtml.push('            </label><br />');
                aHtml.push('            <span style="font-size:10px;">Om dit venster weer te openen klikt u op de knop \'Help\' op de kaart.</span></div>');
                aHtml.push('    </div>');
                aHtml.push('</div>');
                break;
        }        
    }
}