Q: select from combo box and redraw the chart I have this requirement, i have set of graphs, what i need to do is redraw them for the same data list when i select the chart type from a combo box,  but i have no idea how to achieve this, need some help please? any tutorials on this? better..

A: A simple way would be to create a controller/method that takes the graph ID or name as argument and generates that graph for you on the fly. Then use jQuery to make ajax calls to this controller/method, fetch the generated graph, and replace the existing one on the page.
Example implementation:
<script type="text/javascript">
    $(function(){
        $('select[name=graphList]').change(function(e){
            e.preventDefault();
            var graphID = $(this).val(); //returns the selected option's value

            // make an ajax call to the method/controller to fetch the new graph HTML
            $.ajax({
                // append (new Date()).getTime() to url to prevent session timeout

                url:"http://your_url_here/controller/method/" + graphID + "/" + (new Date()).getTime(),
                    success: function(data){
                            // data should now contain the graph HTML for the new generated graph
                            // simply put this html into the graph div
                            $('#graph').html(data);
                        }
            });
        });
    });
</script>

<!-- HTML example below -->
<select name="graphList">
    <option value="1">Graph 1</option>
    <option value="2">Graph 2</option>
    <option value="3">Graph 3</option>
</select>

<div id="graph">

</div>

