我试图更新flot库，以便在我们的Web应用程序中创建图表。更新后，图例不再显示。我在options.legend对象中使用了labelFormatter。
API文档https://github.com/flot/flot/blob/master/API.md#customizing-the-legend中的示例
为每个图例项目创建一个链接：<a href="#' + label + '">' + label + '</a>在版本3.0.0中仍然有效。
但是在0.8.3版本中，我们曾经有一个复选框和一个标签：
<input type='checkbox'></input><label>" + label + "</label>。
而且这不再出现。它位于html文档的DOM元素中，但其大小似乎为零。
自今年1月（2019年）以来，似乎有很多新的发行版本：https://github.com/flot/flot/releases
我尝试了2.1.1、3.0.0和3.0.2。它们都表现出相同的行为。
这是来自http://www.flotcharts.org/flot/examples/series-toggle/index.html的flot“切换系列”示例，对其进行了稍加修改，使其具有lableFormatter，该lableFormatter在图例中提供了一个复选框和一个标签。
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Flot Examples: Toggling Series</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 datasets = {
"usa": {
label: "USA",
data: [[1988, 483994], [1989, 479060], [1990, 457648], [1991, 401949], [1992, 424705], [1993, 402375], [1994, 377867], [1995, 357382], [1996, 337946], [1997, 336185], [1998, 328611], [1999, 329421], [2000, 342172], [2001, 344932], [2002, 387303], [2003, 440813], [2004, 480451], [2005, 504638], [2006, 528692]]
},
"russia": {
label: "Russia",
data: [[1988, 218000], [1989, 203000], [1990, 171000], [1992, 42500], [1993, 37600], [1994, 36600], [1995, 21700], [1996, 19200], [1997, 21300], [1998, 13600], [1999, 14000], [2000, 19100], [2001, 21300], [2002, 23600], [2003, 25100], [2004, 26100], [2005, 31100], [2006, 34700]]
},
"uk": {
label: "UK",
data: [[1988, 62982], [1989, 62027], [1990, 60696], [1991, 62348], [1992, 58560], [1993, 56393], [1994, 54579], [1995, 50818], [1996, 50554], [1997, 48276], [1998, 47691], [1999, 47529], [2000, 47778], [2001, 48760], [2002, 50949], [2003, 57452], [2004, 60234], [2005, 60076], [2006, 59213]]
},
"germany": {
label: "Germany",
data: [[1988, 55627], [1989, 55475], [1990, 58464], [1991, 55134], [1992, 52436], [1993, 47139], [1994, 43962], [1995, 43238], [1996, 42395], [1997, 40854], [1998, 40993], [1999, 41822], [2000, 41147], [2001, 40474], [2002, 40604], [2003, 40044], [2004, 38816], [2005, 38060], [2006, 36984]]
},
"denmark": {
label: "Denmark",
data: [[1988, 3813], [1989, 3719], [1990, 3722], [1991, 3789], [1992, 3720], [1993, 3730], [1994, 3636], [1995, 3598], [1996, 3610], [1997, 3655], [1998, 3695], [1999, 3673], [2000, 3553], [2001, 3774], [2002, 3728], [2003, 3618], [2004, 3638], [2005, 3467], [2006, 3770]]
},
"sweden": {
label: "Sweden",
data: [[1988, 6402], [1989, 6474], [1990, 6605], [1991, 6209], [1992, 6035], [1993, 6020], [1994, 6000], [1995, 6018], [1996, 3958], [1997, 5780], [1998, 5954], [1999, 6178], [2000, 6411], [2001, 5993], [2002, 5833], [2003, 5791], [2004, 5450], [2005, 5521], [2006, 5271]]
},
"norway": {
label: "Norway",
data: [[1988, 4382], [1989, 4498], [1990, 4535], [1991, 4398], [1992, 4766], [1993, 4441], [1994, 4670], [1995, 4217], [1996, 4275], [1997, 4203], [1998, 4482], [1999, 4506], [2000, 4358], [2001, 4385], [2002, 5269], [2003, 5066], [2004, 5194], [2005, 4887], [2006, 4891]]
}
};
// hard-code color indices to prevent them from shifting as
// countries are turned on/off
var i = 0;
$.each(datasets, function(key, val) {
val.color = i;
++i;
});
// insert checkboxes
var choiceContainer = $("#choices");
$.each(datasets, function(key, val) {
choiceContainer.append("<br/><input type='checkbox' name='" + key +
"' checked='checked' id='id" + key + "'></input>" +
"<label for='id" + key + "'>"
+ val.label + "</label>");
});
choiceContainer.find("input").click(plotAccordingToChoices);
function plotAccordingToChoices() {
var data = [];
choiceContainer.find("input:checked").each(function () {
var key = $(this).attr("name");
if (key && datasets[key]) {
data.push(datasets[key]);
}
});
if (data.length > 0) {
$.plot("#placeholder", data, {
legend: {
show: true,
labelFormatter: function(label, series) {
/* series is the series object for the label */
return "<input type='checkbox'></input><label>" + label + "</label>"
//return '<a href="#' + label + '">' + label + '</a>';
}
},
yaxis: {
min: 0
},
xaxis: {
tickDecimals: 0
}
});
}
}
plotAccordingToChoices();
// Add the Flot version string to the footer
$("#footer").prepend("Flot " + $.plot.version + " – ");
});
</script>
</head>
<body>
<div id="header">
<h2>Toggling Series</h2>
</div>
<div id="content">
<div class="demo-container">
<div id="placeholder" class="demo-placeholder" style="float:left; width:675px;"></div>
<p id="choices" style="float:right; width:135px;"></p>
</div>
<p>This example shows military budgets for various countries in constant (2005) million US dollars (source: <a href="http://www.sipri.org/">SIPRI</a>).</p>
<p>Since all data is available client-side, it's pretty easy to make the plot interactive. Try turning countries on and off with the checkboxes next to the plot.</p>
</div>
<div id="footer">
Copyright © 2007 - 2014 IOLA and Ole Laursen
</div>
</body>
</html>
图例项目在flot 0.8.3中正确显示，但在2.1.1或更高版本中不可见。
flot的最新发行版中似乎还有更多更改，这只是最明显的更改之一。有谁知道在这些新版本中如何处理该labelFormatter？ 谢谢！