我试图通过向为列绘制的 SVG 矩形添加渐变来向 Google ColumnChart 添加一些 pizazz。下面的代码将向 iframe svg>defs 添加渐变，并在我目前关心的所有浏览器(Firefox、IE 和 Chrome 的更高版本)中正确替换 rects 的填充属性。
我的问题是，每当我将鼠标悬停在或选择一个栏(或图例)时，颜色都会重置回原始颜色。我是一个 SVG 菜鸟，我一直无法弄清楚如何、在哪里或什么是重置颜色。
所以我的问题是有人知道如何(使用 javascript/jquery)停止、覆盖或以某种方式操纵重置颜色的代码？如果可能，我更愿意保持“交互式”部分完整(工具提示等)。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<title>Google Visualization API Sample</title>
<script type="text/javascript" src="http://www.google.com/jsapi"></script>
<script type="text/javascript">
google.load('visualization', '1', {packages: ['corechart']});
google.load("jquery", "1.7.1");
</script>
<script type="text/javascript">
function drawVisualization() {
// Create and populate the data table.
var data = new google.visualization.DataTable();
var rowData = [['Year', 'North', 'West', 'South'],
['2010', 197, 333, 298 ],
['2011', 167, 261, 381 ]];
var data = google.visualization.arrayToDataTable(rowData);
visualization = new google.visualization.ColumnChart(document.getElementById('visualization'));
google.visualization.events.addListener(visualization, 'ready', function(){
var svgns = "http://www.w3.org/2000/svg";
var gradients = [["red","#C0504D","#E6B8B7"],
["green","#9BBB59","#D8E4BC"],
["blue","#4F81BD","DCE6F1"]];
var svg_defs = $("#visualization iframe").contents().find('defs');
// add gradients to svg defs
for(var i = 0; i < gradients.length; i++){
var grad = $(document.createElementNS(svgns, "linearGradient")).
attr({id:gradients[i][0],x1:"0%",x2:"0%",y1:"0%",y2:"100%"});
var stopTop = $(document.createElementNS(svgns, "stop")).
attr({offset:"0%","stop-color":gradients[i][1]});
var stopBottom = $(document.createElementNS(svgns, "stop")).
attr({offset:"100%","stop-color":gradients[i][2]});
$(grad).append(stopTop).append(stopBottom);
svg_defs.append(grad);
}
// #3366cc, #dc3912, #ff9900 - replace default colors with gradients
$("#visualization iframe").contents().find('rect[fill="#3366cc"]').attr({'fill':'url(#blue)','stroke-width':0.4,'stroke':'#000000'});
$("#visualization iframe").contents().find('rect[fill="#dc3912"]').attr({'fill':'url(#blue)','stroke-width':0.4,'stroke':'#000000'});
$("#visualization iframe").contents().find('rect[fill="#ff9900"]').attr({'fill':'url(#blue)','stroke-width':0.4,'stroke':'#000000'});
});
// Create and draw the visualization.
visualization.draw(data,{width:600, height:400});
}
google.setOnLoadCallback(drawVisualization);
</script>
</head>
<body style="font-family: Arial;border: 0 none;">
<div id="visualization" style="width: 600px; height: 400px;"></div>
</body>
</html>
更新
因此，在查看 DOM 以查看是否可以找到这些颜色代码的存储位置(并通过查找正在使用它们的函数)时，我确实找到了这些(设置后将执行我想要的操作):
//fill
visualization.qa.l.e[0].Hm.O = "url(#blue)";
visualization.qa.l.e[1].Hm.O = "url(#red)";
visualization.qa.l.e[2].Hm.O = "url(#green)";
// stroke
visualization.qa.l.e[0].Hm.Jb = "#000000";
visualization.qa.l.e[1].Hm.Jb = "#000000";
visualization.qa.l.e[2].Hm.Jb = "#000000";
// fill-opacity
//visualization.qa.l.e[0].Hm.$b = 0.5;
//visualization.qa.l.e[1].Hm.$b = 0.5;
//visualization.qa.l.e[2].Hm.$b = 0.5;
// stroke-width
visualization.qa.l.e[0].Hm.H = 0.4;
visualization.qa.l.e[1].Hm.H = 0.4;
visualization.qa.l.e[2].Hm.H = 0.4;
// stroke-opacity
//visualization.qa.l.e[0].Hm.nc = 0.5;
//visualization.qa.l.e[1].Hm.nc = 0.5;
//visualization.qa.l.e[2].Hm.nc = 0.5;
但这只是一个临时解决方案，因为我确定下一次 Google 更新可视化代码时，这些变量名称会发生变化(我认为有人不会故意选择这些名称，并且使用的压缩器/混淆器可能会选择不同的变量名称)下次 - 但谁知道 - 也许不会)。
因此，如果有人知道不依赖于手动查找和设置变量名称的更持久的方式，我会喜欢它。否则，这可能是我目前最好的选择。
更新2 (2012 年 3 月 1 日)
举个例子。现在移动变量:
//fill
visualization.da.C.d[0].en.S = "url(#blue)";
最佳答案
您可以使用 MutationObserver知道何时对 svg 进行了更改
从 'ready' 移动代码observer 的事件监听器
覆盖重置颜色的代码
如以下代码段所示...
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<title>Google Visualization API Sample</title>
<script type="text/javascript" src="http://www.google.com/jsapi"></script>
<script type="text/javascript">
google.load('visualization', '1', {packages: ['corechart']});
google.load("jquery", "1.7.1");
</script>
<script type="text/javascript">
function drawVisualization() {
// Create and populate the data table.
var data = new google.visualization.DataTable();
var rowData = [['Year', 'North', 'West', 'South'],
['2010', 197, 333, 298 ],
['2011', 167, 261, 381 ]];
var data = google.visualization.arrayToDataTable(rowData);
var chartDiv = document.getElementById('visualization');
visualization = new google.visualization.ColumnChart();
// observe changes to the chart container
var observer = new MutationObserver(function () {
var svgns = "http://www.w3.org/2000/svg";
var gradients = [["red","#C0504D","#E6B8B7"],
["green","#9BBB59","#D8E4BC"],
["blue","#4F81BD","DCE6F1"]];
var svg_defs = $("#visualization iframe").contents().find('defs');
// add gradients to svg defs
for(var i = 0; i < gradients.length; i++){
var grad = $(document.createElementNS(svgns, "linearGradient")).
attr({id:gradients[i][0],x1:"0%",x2:"0%",y1:"0%",y2:"100%"});
var stopTop = $(document.createElementNS(svgns, "stop")).
attr({offset:"0%","stop-color":gradients[i][1]});
var stopBottom = $(document.createElementNS(svgns, "stop")).
attr({offset:"100%","stop-color":gradients[i][2]});
$(grad).append(stopTop).append(stopBottom);
svg_defs.append(grad);
}
// #3366cc, #dc3912, #ff9900 - replace default colors with gradients
$("#visualization iframe").contents().find('rect[fill="#3366cc"]').attr({'fill':'url(#blue)','stroke-width':0.4,'stroke':'#000000'});
$("#visualization iframe").contents().find('rect[fill="#dc3912"]').attr({'fill':'url(#blue)','stroke-width':0.4,'stroke':'#000000'});
$("#visualization iframe").contents().find('rect[fill="#ff9900"]').attr({'fill':'url(#blue)','stroke-width':0.4,'stroke':'#000000'});
});
observer.observe(chartDiv, {
childList: true,
subtree: true
});
// Create and draw the visualization.
visualization.draw(data,{width:600, height:400});
}
google.setOnLoadCallback(drawVisualization);
</script>
</head>
<body style="font-family: Arial;border: 0 none;">
<div id="visualization" style="width: 600px; height: 400px;"></div>
</body>
</html>
关于svg - 向 Google-Visualization ColumnChart 添加渐变，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/9217065/