RGraph/docs/dynamic.html

   1 <?php ob_start('ob_gzhandler') ?>
   2 <!DOCTYPE html>
   3 <html>
   4 <head>
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   9         * | This file is part of the RGraph package - you can learn more at:             |
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  13         * | This package is licensed under the RGraph license. For all kinds of business |
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  20     -->
  21     <title>RGraph: HTML5 canvas graph library - Retrieving a PNG of your graph</title>
  22
  23     <meta name="keywords" content="rgraph html5 canvas graph docs png image" />
  24     <meta name="description" content="RGraph: HTML5 canvas graph library - Retrieving a PNG representation of your graph" />
  25
  26     <link rel="stylesheet" href="../css/website.css" type="text/css" media="screen" />
  27     <link rel="icon" type="image/png" href="/favicon.png">
  28
  29     <script src="../libraries/RGraph.common.core.js" ></script>
  30     <script src="../libraries/RGraph.common.context.js" ></script>
  31     <script src="../libraries/RGraph.line.js" ></script>
  32     <!--[if IE 8]><script src="../excanvas/excanvas.compressed.js"></script><![endif]-->
  33
  34 </head>
  35 <body>
  36
  37     <!-- Social networking buttons -->
  38     <script src="../libraries/RGraph.common.core.js" ></script>
  39
  40     <script>
  41         function HideTwitterDIV ()
  42         {
  43             document.getElementById("twitter_div").style.opacity = 0;
  44             document.getElementById("twitter_div").style.display = 'none';
  45         }
  46
  47
  48         function ShowTwitterDIV (e)
  49         {
  50             var e   = RGraph.FixEventObject(document.all ? event : e);
  51             var div = document.getElementById("twitter_div");
  52             var img = document.getElementById("twitter_icon");
  53
  54             div.style.display = 'block';
  55             div.style.left    = (RGraph.getCanvasXY(img)[0] + img.offsetWidth - div.offsetWidth + 110) + 'px';
  56             div.style.top     = (RGraph.getCanvasXY(img)[1] - 1) + 'px';
  57
  58             /**
  59             * Fade it in
  60             */
  61             setTimeout('document.getElementById("twitter_div").style.opacity = 0.2;', 25);
  62             setTimeout('document.getElementById("twitter_div").style.opacity = 0.4;', 50);
  63             setTimeout('document.getElementById("twitter_div").style.opacity = 0.6;', 100);
  64             setTimeout('document.getElementById("twitter_div").style.opacity = 0.8;', 125);
  65             setTimeout('document.getElementById("twitter_div").style.opacity = 1.0;', 150);
  66
  67             e.stopPropagation();
  68
  69             return false;
  70         }
  71
  72         /**
  73         * This code installs the event handler that hides the Twitter DIV
  74         */
  75         if (RGraph.isIE8()) {
  76              window.attachEvent('onload', function () {document.body.attachEvent('onclick', HideTwitterDIV);});
  77         } else {
  78             window.addEventListener('click', HideTwitterDIV, false);
  79         }
  80     </script>
  81
  82     <!-- The twitter DIV -->
  83     <div id="twitter_div" style="position: absolute;top: 0;left: 0;background-color: #eee;border: 2px dashed black;box-shadow: 0 0 15px #aaa;-moz-box-shadow: 0 0 15px #aaa;-webkit-box-shadow: 0 0 15px #aaa;padding: 3px;display: none;opacity: 0;z-index: 99;">
  84         <a href="http://twitter.com/home/?status=RGraph%3A+HTML5+canvas+graph+library+based+on+the+HTML5+canvas+tag+http%3A%2F%2Fwww.rgraph.net+%23rgraph+%23html5+%23canvas" target="_blank" title="Share on Twitter" rel="nofollow" style="text-decoration: none">Tweet&nbsp;about&nbsp;RGraph</a><br>
  85         <a href="http://twitter.com/_rgraph" style="text-decoration: none" rel="nofollow" target="_blank">Follow for HTML5 news</a>
  86     </div>
  87
  88     <div id="social_icons" class="warning" style="top: 0; left: 5px; position: absolute">
  89         <script>
  90             // Opera fix
  91             if (navigator.userAgent.indexOf('Opera') == -1) {
  92               document.getElementById("social_icons").style.position = 'fixed';
  93               document.getElementById("twitter_div").style.position = 'fixed';
  94
  95             }
  96         </script>
  97
  98         <b style="display: inline-block; position: relative; top: 1px">Bookmark and share:</b>
  99
 100
 101             <div id="social">
 102                 <a title="Bookmark with delicious" href="http://delicious.com/save?jump=close&v=4&noui&jump=close&url=http://www.rgraph.net&notes=RGraph%20is%20a%20HTML5%20based%20graph%20library%20supporting%20a%20wide%20range%20of%20different%20graph%20types:Bar,%20Bipolar,%20Donut,%20Funnel,%20Gantt,%20Horizontal%20Bar,%20LED,%20Line,%20Meter,%20Odometer,%20Pie,%20Progress%20Bar,%20Rose,%20RScatter,%20Scatter%20and%20Traditional%20Radar&title=RGraph:%20HTML5%20canvas%20graph%20library%20based%20on%20the%20HTML5%20canvas%20tag" target="_blank">
 103                     <img src="../images/delicious.png" alt="Bookmark with delicious" width="22" height="22" border="0" align="absmiddle" />
 104                 </a>
 105
 106                 <a href="" target="_blank" onmouseover="if (document.getElementById('twitter_div').style.display == 'none') ShowTwitterDIV(event);" onclick="event.stopPropagation(); event.cancelBubble = true; return false">
 107                     <img src="../images/twitter.png" id="twitter_icon" alt="tweet this site" width="22" height="22" border="0" align="absmiddle" />
 108                 </a>
 109
 110
 111 <!--
 112                 <a title="Post to Google Buzz!" href="" onclick="window.open('http://www.google.com/buzz/post?url=http://www.rgraph.net&imageurl=http://www.rgraph.net/images/logo.png', 'google_buzz_window', 'width=800,height=400,top=100,left=100'); return false">
 113                     <img src="../images/buzz.png" width="22" height="22" alt="Post to Google Buzz!" align="absmiddle" style="position: relative; top: -2px; border: 0" border="0"/>
 114                 </a>
 115
 116
 117                 <a title="Share RGraph on Facebook" href="" onclick="window.open('http://www.facebook.com/sharer.php?u=http://www.rgraph.net&t=RGraph:%20HTML5%20canvas%20graph%20library', 'facebook_window', 'width=500,height=300,top=100,left=100'); return false">
 118                     <img src="../images/facebook.png" width="22" height="22" alt="Post to Facebook" align="absmiddle" style="position: relative; top: -2px; border: 0" border="0"/>
 119                 </a>
 120
 121                 <a href="mailto:share@friendfeed.com" title="Share on FriendFeed">
 122                     <img src="../images/friendfeed.png" width="22" height="22" alt="Share on FriendFeed" border="0" align="absmiddle" />
 123                 </a>
 124
 125                 <a href="http://www.stumbleupon.com/submit?url=http://www.rgraph.net" target="_blank" title="Share on StumbleUpon" >
 126                     <img src="../images/stumble.png" alt="Stumble! this site" width="22" height="22" border="0" align="absmiddle" />
 127                 </a>
 128 -->
 129             </div>
 130     </div>
 131     <!-- /Social networking buttons -->
 132
 133
 134 <div id="breadcrumb">
 135     <a href="../index.html">RGraph: HTML5 canvas graph library</a>
 136     >
 137     <a href="index.html">Documentation</a>
 138     >
 139     Updating your graphs dynamically
 140 </div>
 141
 142     <h1>RGraph: HTML5 canvas graph library - Updating your graphs dynamically</h1>
 143
 144     <script>
 145         if (RGraph.isIE8()) {
 146             document.write('<div style="background-color: #fee; border: 2px dashed red; padding: 5px"><b>Important</b><br /><br /> Internet Explorer 8 does not natively support the HTML5 canvas tag, so if you want to see the graphs, you can either:<ul><li>Install <a href="http://code.google.com/chrome/chromeframe/">Google Chrome Frame</a></li><li>Use ExCanvas. This is provided in the RGraph Archive.</li><li>Use another browser entirely. Your choices are Firefox 3.5+, Chrome 2+, Safari 4+ or Opera 10.5+. </li></ul> <b>Note:</b> Internet Explorer 9 fully supports the canvas tag. Click <a href="http://groups.google.com/group/rgraph/browse_thread/thread/c5651ff8c56b8f3c#" target="_blank">here</a> to see some screenshots.</div>');
 147         }
 148     </script>
 149
 150     <canvas id="cvs" width="600" height="250" style="float: right">[No canvas support]</canvas>
 151     <script>
 152         window.onload = function (e)
 153         {
 154             d1 = [];
 155             d2 = [];
 156
 157             // Pre-pad the arrays with 100 null values
 158             for (var i=0; i<400; ++i) {
 159                 d1.push(null);
 160                 d2.push(null);
 161             }
 162
 163             function getGraph(id, d1, d2)
 164             {
 165                 var graph = new RGraph.Line(id, d1, d2);
 166                 graph.Set('chart.xticks', 100);
 167                 graph.Set('chart.gutter', 25);
 168                 graph.Set('chart.background.barcolor1', 'white');
 169                 graph.Set('chart.background.barcolor2', 'white');
 170                 graph.Set('chart.title.xaxis', 'Time >>>');
 171                 graph.Set('chart.title.yaxis', 'Bandwidth (MB/s)');
 172                 graph.Set('chart.title', 'Bandwidth used by servers 1 and 2');
 173                 graph.Set('chart.filled', true);
 174                 graph.Set('chart.fillstyle', ['#daf1fa', '#faa']);
 175                 graph.Set('chart.colors', ['rgb(169, 222, 244)', 'red']);
 176                 graph.Set('chart.linewidth', 1);
 177                 //graph.Set('chart.ylabels.inside', true);
 178                 graph.Set('chart.yaxispos', 'right');
 179                 graph.Set('chart.ymax', 20);
 180                 graph.Set('chart.xticks', 25);
 181
 182                 return graph;
 183             }
 184
 185             function drawGraph ()
 186             {
 187                 RGraph.Clear(document.getElementById("cvs"));
 188
 189                 var graph = getGraph('cvs', d1, d2);
 190                 graph.Draw();
 191
 192                 // Add some data to the data arrays
 193                 var r1 = RGraph.random(7, 9);
 194                 var r2 = RGraph.random(7, 10);
 195
 196                 d1.push(r1);
 197                 d2.push(r2);
 198
 199                 if (d1.length > 400) {
 200                     d1 = RGraph.array_shift(d1);
 201                     d2 = RGraph.array_shift(d2);
 202                 }
 203
 204                 if (document.all && RGraph.isIE8()) {
 205                     alert('[MSIE] Sorry, Internet Explorer 8 is not fast enough to support animated charts');
 206                 } else {
 207                     setTimeout(drawGraph,15);
 208                 }
 209             }
 210
 211             drawGraph();
 212         }
 213     </script>
 214
 215     <p>
 216         The example on the right shows a  line chart that automatically updates itself every 250 milliseconds. An ideal
 217         use for this could be showing a networks bandwidth usage, or a servers load value.
 218     </p>
 219
 220     <p>
 221         This particular example shows a stacked line chart with two data series, though if you're showing load/stress values, a
 222         non-filled chart might be a better choice.
 223     </p>
 224
 225     <p>
 226         To get up-to-date data from your server you could simply have the page refresh itself, storing the data on the server,
 227         or use <a href="index.html#ajax">AJAX</a> if you want the data stored client-side.
 228     </p>
 229
 230     <p>
 231         Be careful of the data types you use to pass the data to RGraph - you should use numbers to represent values, not strings.
 232     </p>
 233
 234     <br clear="all" />
 235
 236     <pre class="code">
 237 &lt;canvas id="cvs" width="600" height="250"&gt;[No canvas support]&lt;/canvas&gt;
 238
 239 &lt;script&gt;
 240     d1 = [];
 241     d2 = [];
 242
 243     // Pre-pad the arrays with 100 null values
 244     for (var i=0; i< 100; ++i) {
 245         d1.push(null);
 246         d2.push(null);
 247     }
 248
 249     function getGraph(id, d1, d2)
 250     {
 251         var graph = new RGraph.Line(id, d1, d2);
 252         graph.Set('chart.gutter', 25);
 253         graph.Set('chart.background.barcolor1', 'white');
 254         graph.Set('chart.background.barcolor2', 'white');
 255         graph.Set('chart.title.xaxis', 'Time');
 256         graph.Set('chart.filled', true);
 257         graph.Set('chart.fillstyle', ['#daf1fa', '#faa']);
 258         graph.Set('chart.colors', ['rgb(169, 222, 244)', 'red']);
 259         graph.Set('chart.linewidth', 3);
 260         graph.Set('chart.ymax', 20);
 261         graph.Set('chart.xticks', 25);
 262
 263         return graph;
 264     }
 265
 266     function drawGraph (e)
 267     {
 268         // Clear the canvas and redraw the graph
 269         RGraph.Clear(document.getElementById("cvs"));
 270         var graph = getGraph('cvs', d1, d2);
 271         graph.Draw();
 272
 273         // Add some data to the data arrays
 274         d1.push(RGraph.random(5, 10));
 275         d2.push(RGraph.random(5, 10));
 276
 277         // Get rid of the first values of the arrays
 278         if (d1.length > 100) {
 279             d1 = RGraph.array_shift(d1);
 280             d2 = RGraph.array_shift(d2);
 281         }
 282
 283         setTimeout(drawGraph,250);
 284     }
 285
 286     drawGraph();
 287 &lt;/script&gt;
 288 </pre>
 289
 290 </body>
 291 </html>