function drawMessages() {
    $("#draw").css('background-image','url(../images/ajax-loader.gif)');
    $.get("/update:Chat:getMessagesHtml", function(data) {
        $("#draw").html(data);
        setPositionOfContent();
        $("#draw").css('background-image','none');        
    });
    setTimeout('drawMessages()',2000);  
}

function alertMessage() {
    mess = document.getElementById('tbox').value;
    if(mess == "") {
        alert("zpráva je prázdná");     
    } else {
        $.post("/update:Chat:addMessage/bid:", {message: mess} , function(data) {drawMessages();});
        document.getElementById('tbox').value = "";        
    }
}

function setPositionOfContent() {
    var tableHeight = $('#sizer').innerHeight();
    var frameHeight = $('#draw').innerHeight();
    var rozdil = (tableHeight-frameHeight);
    
    
    if(rozdil >= 1) {
        $('#cho').css('margin-top','-' + rozdil + 'px');
    } else {
        rozdil = -rozdil;
        $('#cho').css('margin-top',rozdil + 'px');    
    }
}