html - Show a div as a modal pop up

Question

I have the following div:

<div id="divAlert">
    <div id='divAlertText'>You must select a language.</div>
    <div id='divAlertButton' class='btn blue' onclick="HideAlert();">Ok</div>
</div>

Is this HTML page there are more divs and buttons. I want to show divAlert as a modal pop up.

I know there is something in jQuery, I think, that I can use to show my div with a half transparent black background filling the entire page. But I can't remember its name.

Any advice?

Answer 1

A simple modal pop up div or dialog box can be done by CSS properties and little bit of jQuery.The basic idea is simple:

1. Create a div with semi transparent background & show it on top of your content page on click. 2. Show your pop up div or alert div on top of the semi transparent dimming/hiding div.

So we need three divs:

content(main content of the site). hider(To dim the content). popup_box(the modal div to display).

First let us define the CSS:

    #hider
    {
        position:absolute;
        top: 0%;
        left: 0%;
        width:1600px;
        height:2000px;
        margin-top: -800px; /*set to a negative number 1/2 of your height*/
        margin-left: -500px; /*set to a negative number 1/2 of your width*/
        /*
        z- index must be lower than pop up box
       */
        z-index: 99;
       background-color:Black;
       //for transparency
       opacity:0.6;
    }

    #popup_box  
    {

    position:absolute;
        top: 50%;
        left: 50%;
        width:10em;
        height:10em;
        margin-top: -5em; /*set to a negative number 1/2 of your height*/
        margin-left: -5em; /*set to a negative number 1/2 of your width*/
        border: 1px solid #ccc;
        border:  2px solid black;
        z-index:100; 

    }

It is important that we set our hider div's z-index lower than pop_up box as we want to show popup_box on top.
Here comes the java Script:

        $(document).ready(function () {
        //hide hider and popup_box
        $("#hider").hide();
        $("#popup_box").hide();

        //on click show the hider div and the message
        $("#showpopup").click(function () {
            $("#hider").fadeIn("slow");
            $('#popup_box').fadeIn("slow");
        });
        //on click hide the message and the
        $("#buttonClose").click(function () {

            $("#hider").fadeOut("slow");
            $('#popup_box').fadeOut("slow");
        });

        });

And finally the HTML:

<div id="hider"></div>
<div id="popup_box">
    Message<br />
    <a id="buttonClose">Close</a>
</div>    
<div id="content">
    Page's main content.<br />
    <a id="showpopup">ClickMe</a>
</div>

I have used jquery-1.4.1.min.js www.jquery.com/download and tested the code in Firefox. Hope this helps.