Reload chart data via JSON with Highcharts

Question

I am trying to reload the data for a Highcharts chart via JSON based on a button click elsewhere in the page. Initially I would like to display a default set of data (spending by category) but then load new data based on user input (spending by month, for example). The easiest way I can think of to output the JSON from the server is by passing a GET request to the PHP page, for example $.get('/dough/includes/live-chart.php?mode=month', retrieving this value from the button's ID attribute.

Here is what I have so far to retrieve the default data (spending by category). Need to find how to load completely different data into the pie chart, based on user input, on demand:

$(document).ready(function() {
            //This is an example of how I would retrieve the value for the button
            $(".clickMe").click(function() {
                var clickID = $(this).attr("id");
            });
            var options = {
                chart: {
                    renderTo: 'graph-container',
                    margin: [10, 175, 40, 40]
                },
                title: {
                    text: 'Spending by Category'
                },
                plotArea: {
                    shadow: null,
                    borderWidth: null,
                    backgroundColor: null
                },
                tooltip: {
                    formatter: function() {
                        return '<b>'+ this.point.name +'</b>: $'+ this.y;
                    }
                },
                credits: {
                    enabled: false
                },
                plotOptions: {
                    pie: {
                        allowPointSelect: true,
                        cursor: 'pointer',
                        dataLabels: {
                            enabled: true,
                            formatter: function() {
                                if (this.y > 5) return '$' + this.y;
                            },
                            color: 'white',
                            style: {
                                font: '13px Trebuchet MS, Verdana, sans-serif'
                            }
                        }
                    }
                },
                legend: {
                    layout: 'vertical',
                    style: {
                        left: 'auto',
                        bottom: 'auto',
                        right: '50px',
                        top: '100px'
                    }
                },
                series: [{
                    type: 'pie',
                    name: 'Spending',
                    data: []
                }]
            };
            $.get('/dough/includes/live-chart.php', function(data) {
            var lines = data.split('\n');
            $.each(lines, function(lineNo, line) {
                var items = line.split(',');
                var data = {};
                $.each(items, function(itemNo, item) {
                    if (itemNo === 0) {
                        data.name = item;
                    } else {
                        data.y = parseFloat(item);
                    }
                });
                options.series[0].data.push(data);
            });
            // Create the chart
            var chart = new Highcharts.Chart(options);
        });
        });

Any help would be greatly appreciated

EDIT

Here is the updated Javascript thanks to Robodude. John, you have me on the right track here - thanks! I'm now getting stuck with how to replace the data on the chart from the AJAX request. I must admit that the code following the $.get() is most likely from sample code, I do not fully understand what is going on when it is run - perhaps there is a better way to format the data?

I was able to make some progress in that the chart now loads new data but it is added on top of what is already there. I suspect that the culprit is this line:

options.series[0].data.push(data);

I tried options.series[0].setData(data); but nothing happens. On the bright side, the AJAX request works flawlessly based on the value of the select menu and there are no Javascript errors. Here is the code in question, sans chart options:

$.get('/dough/includes/live-chart.php?mode=cat', function(data) {
            var lines = data.split('\n');
            $.each(lines, function(lineNo, line) {
                var items = line.split(',');
                var data = {};
                $.each(items, function(itemNo, item) {
                    if (itemNo === 0) {
                        data.name = item;
                    } else {
                        data.y = parseFloat(item);
                    }
                });
                options.series[0].data.push(data);
            });
            // Create the chart
            var chart = new Highcharts.Chart(options);
        });
        $("#loadChart").click(function() {
            var loadChartData = $("#chartCat").val();
                $.get('/dough/includes/live-chart.php?mode=' + loadChartData, function(data) {
                var lines = data.split('\n');
                $.each(lines, function(lineNo, line) {
                    var items = line.split(',');
                    var data = {};
                    $.each(items, function(itemNo, item) {
                        if (itemNo === 0) {
                            data.name = item;
                        } else {
                            data.y = parseFloat(item);
                        }
                    });
                    options.series[0].data.push(data);
                });
                // Create the chart
                var chart = new Highcharts.Chart(options);
            });
        });
    });

EDIT 2 This is the format that the chart is pulling from - very simple, category name and value with \n after each.

Coffee, 4.08
Dining Out, 5.05
Dining: ODU, 5.97
Dining: Work, 38.41
Entertainment, 4.14
Gas, 79.65
Groceries, 228.23
Household, 11.21
Misc, 12.20
Snacks, 20.27

Answer 1

The other answers didn't work for me. I found the answer in their documentation:

http://api.highcharts.com/highcharts#Series

Using this method (see JSFiddle example):

var chart = new Highcharts.Chart({
    chart: {
        renderTo: 'container'
    },

    series: [{
        data: [29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4]        
    }]
});

// the button action
$('#button').click(function() {
    chart.series[0].setData([129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4, 29.9, 71.5, 106.4] );
});