Keep a jQuery dialog in a div

Question

I am trying to create a number of jQuery dialogs but I would like to constrain their positions to inside a parent div. I am using the following code to create them (on a side note the oppacity option is not working either...):

var d= $('<div title="Title goes here"></div>').dialog({
            autoOpen: true,
            closeOnEscape: false,
            draggable: true,
            resizable: false,
            width: dx,
            height: dy
        });

        d.draggable('option', 'containment', 'parent');
        d.draggable('option', 'opacity', 0.45);

        $('#controlContent').append(d.parent());

Answer 1

A bit more helpful and complete version of above solution.

It even limits the resizing outside of the div too!

And the JavaScript is fully commented.

// Public Domain
// Feel free to use any of the JavaScript, HTML, and CSS for any commercial or private projects. No attribution required.
// I'm not responsible if you blow anything up with this code (or anything else you could possibly do with this code).

jQuery(function($) 
{ 
    // When the document is ready run the code inside the brackets.
    $("button").button(); // Makes the button fancy (ie. jquery-ui styled)
    $("#dialog").dialog(
    { 
        // Set the settings for the jquery-ui dialog here.
        autoOpen: false, // Don't open the dialog instantly. Let an event such as a button press open it. Optional.
        position: { my: "center", at: "center", of: "#constrained_div" } // Set the position to center of the div.
    }).parent().resizable(
    { 
        // Settings that will execute when resized.
        containment: "#constrained_div" // Constrains the resizing to the div.
    }).draggable(
    { 
        // Settings that execute when the dialog is dragged. If parent isn't used the text content will have dragging enabled.
        containment: "#constrained_div", // The element the dialog is constrained to.
        opacity: 0.70 // Fancy opacity. Optional.
    });

    $("#button").click(function() 
    { 
        // When our fancy button is pressed the stuff inside the brackets will be executed.
        $("#dialog").dialog("open"); // Opens the dialog.
    });
});

http://jsfiddle.net/emilhem/rymEh/33/