dialog is not displaying with proper height in jquery

Question

I'm appending the jquery dialog to body. I'm setting the height to the dialog.

// Create timeout warning dialog
       $('body').append('<div id="sessionTimeout-dialog" title="' 
                        + opts.title 
                        + '"><p>' 
                        + opts.message 
                        + '</p><span id="sessionTimeout-timer"></span>&nbsp;seconds.</div>');

       $('#sessionTimeout-dialog').dialog({
            autoOpen: false,
            resizable: false,
            minWidth: 0,
            width: 300,
            minHeight: 0,
            height: 400,
            modal: true,
            closeOnEscape: false,
            open: function () {
                //removes the right top close(X) button from the dialog
                $(".ui-dialog-titlebar-close").hide();
                //$(this).dialog('option', 'maxHeight', 500);
            },
            buttons: {
                // Logout button, closes the dialog and takes user to logout URL
                "Log Out Now": function () {
                    $(this).dialog('close');
                    //window.location = 'home.php';
                    window.location = ''+opts.logoutUrl;
                },
                // Stay button, closes dialog
                "Stay Connected": function () {
                    latestActivity = new Date();
                    $(this).dialog('close');
                }
            }
       });

But it still showing the gap before the title of the dialog. Please see the attached output dialog. Need quick help on this.

Answer 1

I was unable to replicate the issue as you described it. I tested with the following:

$(function() {
  var opts = {
    title: "Session Timeout",
    message: "Your session has timed out.",
    logoutUrl: "logout.php"
  };

  function makeDiv(o) {
    if (o == undefined) {
      o = {
        id: "session-timeout-dialog"
      };
    }
    return $("<div>", o).html(opts.message).appendTo("body");
  }

  function makeDialog(tObj) {
    tObj.dialog({
      autoOpen: false,
      classes: {
        "ui-dialog": "no-close"
      },
      resizable: false,
      minWidth: 0,
      width: 300,
      minHeight: 0,
      height: 300,
      modal: true,
      closeOnEscape: false,
      title: opts.title,
      buttons: {
        "Log Out Now": function() {
          $(this).dialog('close');
          window.location = '' + opts.logoutUrl;
        },
        "Stay Connected": function() {
          latestActivity = new Date();
          $(this).dialog('close');
        }
      }
    });
  }

  $("#trigger").click(function() {
    var timeOut = makeDiv();
    makeDialog(timeOut);
    timeOut.dialog("open");
  });
});

.no-close .ui-dialog-titlebar-close {
  display: none;
}

<link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/smoothness/jquery-ui.css">
<script src="//code.jquery.com/jquery-1.12.4.js"></script>
<script src="//code.jquery.com/ui/1.12.1/jquery-ui.js"></script>

<button id="trigger">Trigger Time Out</button>

The height is correct. I suspect, based on your image, that there are other styles being applied that are not shown in your example code. Please Inspect and review all CSS that is applied.

Hope that helps.