Resize elements by dragging divider handler

Question

I want to be able to drag a divider up and down to resize the divs above and below the divider on a fixed page height. These divs could be in a table, although they need not

Answer 1

Here is another alternative to Nick's version, it automatically moves the horizontal handler to the top and to zero as a nice effect. Also, it adjusts the height size of both sections mutually.

$('.horizontal_handler').draggable({

        axis: 'y', 
        containment: 'parent',
        helper: 'clone', 
        drag: function (event, ui) { 

            var height = ui.offset.top - 220 // 220 : initial top margin to the previousDiv
            , referenceHeight = nextDivHeight + previousDivHeight  //500 px initial height size
            , previousSection = $(this).prev()
            , nextSection = $(this).next();

            if ((nextSection.height() === 0) && (referenceHeight - height < 0)){
                return;
            }

            previousSection.height(height); 
            nextSection.height(referenceHeight - height ) ;


            if (nextSection.height()< 20){
                    previousSection.height( height+ nextSection.height() );
                    nextSection.height(0);
                }

            if (previousSection.height()< 20){
                    nextSection.height(referenceHeight - height - previousSection.height() );
                    previousSection.height(0); 
                }
        } 
    });