| 提交 | 用户 | 时间 | ||
| 58d006 | 1 | # Flot [](https://travis-ci.org/flot/flot) |
| A | 2 | |
| 3 | ## About ## | |
| 4 | ||
| 5 | Flot is a Javascript plotting library for jQuery. | |
| 6 | Read more at the website: <http://www.flotcharts.org/> | |
| 7 | ||
| 8 | Take a look at the the examples in examples/index.html; they should give a good | |
| 9 | impression of what Flot can do, and the source code of the examples is probably | |
| 10 | the fastest way to learn how to use Flot. | |
| 11 | ||
| 12 | ||
| 13 | ## Installation ## | |
| 14 | ||
| 15 | Just include the Javascript file after you've included jQuery. | |
| 16 | ||
| 17 | Generally, all browsers that support the HTML5 canvas tag are | |
| 18 | supported. | |
| 19 | ||
| 20 | For support for Internet Explorer < 9, you can use [Excanvas] | |
| 21 | [excanvas], a canvas emulator; this is used in the examples bundled | |
| 22 | with Flot. You just include the excanvas script like this: | |
| 23 | ||
| 24 | ```html | |
| 25 | <!--[if lte IE 8]><script language="javascript" type="text/javascript" src="excanvas.min.js"></script><![endif]--> | |
| 26 | ``` | |
| 27 | ||
| 28 | If it's not working on your development IE 6.0, check that it has | |
| 29 | support for VML which Excanvas is relying on. It appears that some | |
| 30 | stripped down versions used for test environments on virtual machines | |
| 31 | lack the VML support. | |
| 32 | ||
| 33 | You can also try using [Flashcanvas][flashcanvas], which uses Flash to | |
| 34 | do the emulation. Although Flash can be a bit slower to load than VML, | |
| 35 | if you've got a lot of points, the Flash version can be much faster | |
| 36 | overall. Flot contains some wrapper code for activating Excanvas which | |
| 37 | Flashcanvas is compatible with. | |
| 38 | ||
| 39 | You need at least jQuery 1.2.6, but try at least 1.3.2 for interactive | |
| 40 | charts because of performance improvements in event handling. | |
| 41 | ||
| 42 | ||
| 43 | ## Basic usage ## | |
| 44 | ||
| 45 | Create a placeholder div to put the graph in: | |
| 46 | ||
| 47 | ```html | |
| 48 | <div id="placeholder"></div> | |
| 49 | ``` | |
| 50 | ||
| 51 | You need to set the width and height of this div, otherwise the plot | |
| 52 | library doesn't know how to scale the graph. You can do it inline like | |
| 53 | this: | |
| 54 | ||
| 55 | ```html | |
| 56 | <div id="placeholder" style="width:600px;height:300px"></div> | |
| 57 | ``` | |
| 58 | ||
| 59 | You can also do it with an external stylesheet. Make sure that the | |
| 60 | placeholder isn't within something with a display:none CSS property - | |
| 61 | in that case, Flot has trouble measuring label dimensions which | |
| 62 | results in garbled looks and might have trouble measuring the | |
| 63 | placeholder dimensions which is fatal (it'll throw an exception). | |
| 64 | ||
| 65 | Then when the div is ready in the DOM, which is usually on document | |
| 66 | ready, run the plot function: | |
| 67 | ||
| 68 | ```js | |
| 69 | $.plot($("#placeholder"), data, options); | |
| 70 | ``` | |
| 71 | ||
| 72 | Here, data is an array of data series and options is an object with | |
| 73 | settings if you want to customize the plot. Take a look at the | |
| 74 | examples for some ideas of what to put in or look at the | |
| 75 | [API reference](API.md). Here's a quick example that'll draw a line | |
| 76 | from (0, 0) to (1, 1): | |
| 77 | ||
| 78 | ```js | |
| 79 | $.plot($("#placeholder"), [ [[0, 0], [1, 1]] ], { yaxis: { max: 1 } }); | |
| 80 | ``` | |
| 81 | ||
| 82 | The plot function immediately draws the chart and then returns a plot | |
| 83 | object with a couple of methods. | |
| 84 | ||
| 85 | ||
| 86 | ## What's with the name? ## | |
| 87 | ||
| 88 | First: it's pronounced with a short o, like "plot". Not like "flawed". | |
| 89 | ||
| 90 | So "Flot" rhymes with "plot". | |
| 91 | ||
| 92 | And if you look up "flot" in a Danish-to-English dictionary, some of | |
| 93 | the words that come up are "good-looking", "attractive", "stylish", | |
| 94 | "smart", "impressive", "extravagant". One of the main goals with Flot | |
| 95 | is pretty looks. | |
| 96 | ||
| 97 | ||
| 98 | ## Notes about the examples ## | |
| 99 | ||
| 100 | In order to have a useful, functional example of time-series plots using time | |
| 101 | zones, date.js from [timezone-js][timezone-js] (released under the Apache 2.0 | |
| 102 | license) and the [Olson][olson] time zone database (released to the public | |
| 103 | domain) have been included in the examples directory. They are used in | |
| 104 | examples/axes-time-zones/index.html. | |
| 105 | ||
| 106 | ||
| 107 | [excanvas]: http://code.google.com/p/explorercanvas/ | |
| 108 | [flashcanvas]: http://code.google.com/p/flashcanvas/ | |
| 109 | [timezone-js]: https://github.com/mde/timezone-js | |
| 110 | [olson]: ftp://ftp.iana.org/tz/ | |
