本章用貴金屬價格, 黃金、白金、白銀及鈀金的現價當作資料, 另外還會介紹如何控條圖的漸層色, 及控制圖表圖例的位置.
橫條圖範例(貴金屬價格)
橫條圖資料
一開始不免俗的一樣是放置定位點, 並且指定寬度和高度, 你可以直在用style設定, 或是指定一個CSS class給定位點.
<style type="text/css">
.mychart{
width:300px;
height:150px;
}
</style>
<div id="flot-placeholder" class="mychart"></div>
var rawData = [
[1582.3, 0], //Gold
[28.95, 1], //Silver
[1603, 2], //Platinum
[774, 3], //Palladium
[1245, 4], //Rhodium
[85, 5], //Ruthenium
[1025, 6] //Iridium
];
var dataSet = [
{ label: "Precious Metal Price", data: rawData, color: "#AB5800" }
];
var ticks = [
[0, "Gold"], [1, "Silver"], [2, "Platinum"], [3, "Palldium"], [4, "Rhodium"], [5, "Ruthenium"], [6, "Iridium"]
];
橫條圖選項
當你繪製橫條圖時, bars.horizontal必須設定為true, 若沒有設定, 就會變成直條圖. 在此範例裡我們設定了bars.fillColor, 這屬性可以接受的值可以是單一顏色(如rgba(255, 255, 255, 0.8))或是漸層色, 我們用的是後者. Flot裡指定漸層色的方法可以是
{ colors: [ color1, color2, ... ] }
{ colors: [ { opacity: 0.8 }, { opacity: 0.1 } ] }
bars: {
align: "center",
barWidth: 0.5,
horizontal: true,
fillColor: { colors: [{ opacity: 0.5 }, { opacity: 1}] },
lineWidth: 1
}
在此我們為了美化刻度標籤的格式, 我們用了jQuery Number Formatter外掛, 讓x軸的值輸出成貨幣格式, 要改變刻度標籤可以複寫axis.tickFormatter, 此函式傳入了2個參數, tick value和axis object, 並且會傳回字串. 而Number Formatter可以到此下載.
而axis.axisLabel則是設定軸標籤, 此功能也是需要加入外掛程式jquery.flot.axislabels.js才能使用.
以下是軸選項的程式碼
xaxis: {
axisLabel: "Price (USD/oz)",
axisLabelUseCanvas: true,
axisLabelFontSizePixels: 12,
axisLabelFontFamily: 'Verdana, Arial',
axisLabelPadding: 10,
max: 2000,
tickColor: "#5E5E5E",
tickFormatter: function (v, axis) {
return $.formatNumber(v, { format: "#,###", locale: "us" });
},
color:"black"
}
yaxis: {
axisLabel: "Precious Metals",
axisLabelUseCanvas: true,
axisLabelFontSizePixels: 12,
axisLabelFontFamily: 'Verdana, Arial',
axisLabelPadding: 3,
tickColor: "#5E5E5E",
ticks: ticks,
color:"black"
}
legend: {
noColumns: 0,
labelBoxBorderColor: "#858585",
position: "ne"
}
呼叫$.plot完成繪圖
最後把上面建立的dataSet以及options帶入$.plot, 就完成了!
$(document).ready(function () {
$.plot($("#flot-placeholder"), dataSet, options);
$("#flot-placeholder").UseTooltip();
});
本範例完整程式碼
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<script src="/js/lib/jquery-1.8.3.min.js" type='text/javascript'></script>
<!--[if lte IE 8]><script language="javascript" type="text/javascript" src="/js/flot/excanvas.min.js"></script><![endif]-->
<script type="text/javascript" src="/js/flot/jquery.flot.min.js"></script>
<script type="text/javascript" src="/js/flot/jquery.flot.axislabels.js"></script>
<script type="text/javascript" src="/js/flot/jshashtable-2.1.js"></script>
<script type="text/javascript" src="/js/flot/jquery.numberformatter-1.2.3.min.js"></script>
<script type="text/javascript">
//******* Precious Metal Price - HORIZONTAL BAR CHART
var rawData = [[1582.3, 0], [28.95, 1],[1603, 2],[774, 3],[1245, 4], [85, 5],[1025, 6]];
var dataSet = [{ label: "Precious Metal Price", data: rawData, color: "#E8E800" }];
var ticks = [[0, "Gold"], [1, "Silver"], [2, "Platinum"], [3, "Palldium"], [4, "Rhodium"], [5, "Ruthenium"], [6, "Iridium"]];
var options = {
series: {
bars: {
show: true
}
},
bars: {
align: "center",
barWidth: 0.5,
horizontal: true,
fillColor: { colors: [{ opacity: 0.5 }, { opacity: 1}] },
lineWidth: 1
},
xaxis: {
axisLabel: "Price (USD/oz)",
axisLabelUseCanvas: true,
axisLabelFontSizePixels: 12,
axisLabelFontFamily: 'Verdana, Arial',
axisLabelPadding: 10,
max: 2000,
tickColor: "#5E5E5E",
tickFormatter: function (v, axis) {
return $.formatNumber(v, { format: "#,###", locale: "us" });
},
color: "black"
},
yaxis: {
axisLabel: "Precious Metals",
axisLabelUseCanvas: true,
axisLabelFontSizePixels: 12,
axisLabelFontFamily: 'Verdana, Arial',
axisLabelPadding: 3,
tickColor: "#5E5E5E",
ticks: ticks,
color: "black"
},
legend: {
noColumns: 0,
labelBoxBorderColor: "#858585",
position: "ne"
},
grid: {
hoverable: true,
borderWidth: 2,
backgroundColor: { colors: ["#171717", "#4F4F4F"] }
}
};
$(document).ready(function () {
$.plot($("#flot-placeholder"), dataSet, options);
$("#flot-placeholder").UseTooltip();
});
var previousPoint = null, previousLabel = null;
$.fn.UseTooltip = function () {
$(this).bind("plothover", function (event, pos, item) {
if (item) {
if ((previousLabel != item.series.label) ||
(previousPoint != item.dataIndex)) {
previousPoint = item.dataIndex;
previousLabel = item.series.label;
$("#tooltip").remove();
var x = item.datapoint[0];
var y = item.datapoint[1];
var color = item.series.color;
//alert(color)
//console.log(item.series.xaxis.ticks[x].label);
showTooltip(item.pageX,
item.pageY,
color,
"<strong>" + item.series.label + "</strong><br>" + item.series.yaxis.ticks[y].label +
" : <strong>" + $.formatNumber(x, { format: "#,###", locale: "us" }) + "</strong> USD/oz");
}
} else {
$("#tooltip").remove();
previousPoint = null;
}
});
};
function showTooltip(x, y, color, contents) {
$('<div id="tooltip">' + contents + '</div>').css({
position: 'absolute',
display: 'none',
top: y - 10,
left: x + 10,
border: '2px solid ' + color,
padding: '3px',
'font-size': '9px',
'border-radius': '5px',
'background-color': '#fff',
'font-family': 'Verdana, Arial, Helvetica, Tahoma, sans-serif',
opacity: 0.9
}).appendTo("body").fadeIn(200);
}
</script>
</head>
<body>
<div style="width:450px;height:300px;text-align:center;margin:10px">
<div id="flot-placeholder" style="width:100%;height:100%;"></div>
</div>
</body>
</html>