grouping draggable objects with jquery-ui draggable

Question

I want to use jquery draggable/droppable to let the user select a group of objects (each one has a checkbox in the corner) and then drag all the selected objects as a group.

Answer 1

What I've done for this is created a function that you give the slave / master elements to, which creates a bind() function for the master (I'm only allowing a drag from the master in this case, you can work around this I'm sure), which makes the slave follow it around using standard jQuery css.

    function overlap(slave,master) {
        $('a#groupTheseBlocks').click(function(){
            master.bind('drag', groupBlocks);
            slave.draggable('disable');

            // remember where the slave is in relation to the master
            sLeftRef = (slave.offset().left - master.offset().left);
            sTopRef = (slave.offset().top - master.offset().top);
        });


        function groupBlocks() {
            var left = master.offset().left;
            var top = master.offset().top;

            slave.draggable('disable');
            slave.css('left', (left + sLeftRef) + 'px');
            slave.css('top', (top + sTopRef) + 'px');

        } 
    }

I guess I'll post more to this once I have a working example. As it stands this is working for me. What is missing is a way to call overlap(slave, master) with the elements you want to group together. I'm doing this in a really specific way. You can clever a way to do it, I'm sure.