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	<title>Flot Examples: AJAX</title>

	<link href="../examples.css" rel="stylesheet" type="text/css">

	<!--[if lte IE 8]><script language="javascript" type="text/javascript" src="../../excanvas.min.js"></script><![endif]-->

	<script language="javascript" type="text/javascript" src="../../jquery.js"></script>

	<script language="javascript" type="text/javascript" src="../../jquery.flot.js"></script>

	<script type="text/javascript">



	$(function() {



		var options = {

			lines: {

				show: true

			},

			points: {

				show: true

			},

			xaxis: {

				tickDecimals: 0,

				tickSize: 1

			}

		};



		var data = [];



		$.plot("#placeholder", data, options);



		// Fetch one series, adding to what we already have



		var alreadyFetched = {};



		$("button.fetchSeries").click(function () {



			var button = $(this);



			// Find the URL in the link right next to us, then fetch the data



			var dataurl = button.siblings("a").attr("href");



			function onDataReceived(series) {



				// Extract the first coordinate pair; jQuery has parsed it, so

				// the data is now just an ordinary JavaScript object



				var firstcoordinate = "(" + series.data[0][0] + ", " + series.data[0][1] + ")";

				button.siblings("span").text("Fetched " + series.label + ", first point: " + firstcoordinate);



				// Push the new data onto our existing data array



				if (!alreadyFetched[series.label]) {

					alreadyFetched[series.label] = true;

					data.push(series);

				}



				$.plot("#placeholder", data, options);

			}



			$.ajax({

				url: dataurl,

				type: "GET",

				dataType: "json",

				success: onDataReceived

			});

		});



		// Initiate a recurring data update



		$("button.dataUpdate").click(function () {



			data = [];

			alreadyFetched = {};



			$.plot("#placeholder", data, options);



			var iteration = 0;



			function fetchData() {



				++iteration;



				function onDataReceived(series) {



					// Load all the data in one pass; if we only got partial

					// data we could merge it with what we already have.



					data = [ series ];

					$.plot("#placeholder", data, options);

				}



				// Normally we call the same URL - a script connected to a

				// database - but in this case we only have static example

				// files, so we need to modify the URL.



				$.ajax({

					url: "data-eu-gdp-growth-" + iteration + ".json",

					type: "GET",

					dataType: "json",

					success: onDataReceived

				});



				if (iteration < 5) {

					setTimeout(fetchData, 1000);

				} else {

					data = [];

					alreadyFetched = {};

				}

			}



			setTimeout(fetchData, 1000);

		});



		// Load the first series by default, so we don't have an empty plot



		$("button.fetchSeries:first").click();



		// Add the Flot version string to the footer



		$("#footer").prepend("Flot " + $.plot.version + " &ndash; ");

	});



	</script>

</head>

<body>



	<div id="header">

		<h2>AJAX</h2>

	</div>



	<div id="content">



		<div class="demo-container">

			<div id="placeholder" class="demo-placeholder"></div>

		</div>



		<p>Example of loading data dynamically with AJAX. Percentage change in GDP (source: <a href="http://epp.eurostat.ec.europa.eu/tgm/table.do?tab=table&init=1&plugin=1&language=en&pcode=tsieb020">Eurostat</a>). Click the buttons below:</p>



		<p>The data is fetched over HTTP, in this case directly from text files. Usually the URL would point to some web server handler (e.g. a PHP page or Java/.NET/Python/Ruby on Rails handler) that extracts it from a database and serializes it to JSON.</p>



		<p>

			<button class="fetchSeries">First dataset</button>

			[ <a href="data-eu-gdp-growth.json">see data</a> ]

			<span></span>

		</p>



		<p>

			<button class="fetchSeries">Second dataset</button>

			[ <a href="data-japan-gdp-growth.json">see data</a> ]

			<span></span>

		</p>



		<p>

			<button class="fetchSeries">Third dataset</button>

			[ <a href="data-usa-gdp-growth.json">see data</a> ]

			<span></span>

		</p>



		<p>If you combine AJAX with setTimeout, you can poll the server for new data.</p>



		<p>

			<button class="dataUpdate">Poll for data</button>

		</p>



	</div>



	<div id="footer">

		Copyright &copy; 2007 - 2014 IOLA and Ole Laursen

	</div>



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