具體腳本語言如下:
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="initial-scale=1.0, user-scalable=no, width=device-width">
<title>熱力圖</title>
<link rel="stylesheet" href="https://cache.amap.com/lbs/static/main1119.css"/>
<script src="https://webapi.amap.com/maps?v=1.4.9&key=您申請的key值"></script>
<script type="text/javascript" src="https://cache.amap.com/lbs/static/addToolbar.js"></script>
<script type="text/javascript" src="//a.amap.com/jsapi_demos/static/resource/heatmapData.js"></script>
</head>
<body>
<div id="container"></div>
<div class="button-group">
<input type="button" class="button" value="顯示熱力圖" onclick="heatmap.show()"/>
<input type="button" class="button" value="關閉熱力圖" onclick="heatmap.hide()"/>
</div>
<script>
var map = new AMap.Map("container", {
resizeEnable: true,
center: [116.418261, 39.921984],
zoom: 11
});
var points=[
{"lng":"116.32497","lat":"39.96696"},
{"lng":"116.616","lat":"40.053016"},
{"lng":"116.34324","lat":"39.95056"},
{"lng":"116.554131","lat":"39.912131"},
{"lng":"116.3483","lat":"39.83151"},
{"lng":"116.36619","lat":"39.75298"}
];
if (!isSupportCanvas()) {
alert('熱力圖僅對支持canvas的瀏覽器適用,您所使用的瀏覽器不能使用熱力圖功能,請換個瀏覽器試試~')
}
//詳細的參數,可以查看heatmap.js的文檔 http://www.patrick-wied.at/static/heatmapjs/docs.html
//參數說明如下:
/* visible 熱力圖是否顯示,默認為true
* opacity 熱力圖的透明度,分別對應heatmap.js的minOpacity和maxOpacity
* radius 勢力圖的每個點的半徑大小
* gradient {JSON} 熱力圖的漸變區間 . gradient如下所示
* {
.2:'rgb(0, 255, 255)',
.5:'rgb(0, 110, 255)',
.8:'rgb(100, 0, 255)'
}
其中 key 表示插值的位置, 0-1
value 為顏色值
*/
var heatmap;
map.plugin(["AMap.Heatmap"], function() {
//初始化heatmap對象
heatmap = new AMap.Heatmap(map, {
radius: 25, //給定半徑
opacity: [0, 0.8]
/*,gradient:{
0.5: 'blue',
0.65: 'rgb(117,211,248)',
0.7: 'rgb(0, 255, 0)',
0.9: '#ffea00',
1.0: 'red'
}*/
});
//設置數據集:該數據為北京部分“公園”數據
heatmap.setDataSet({
data: points,
max: 100
});
});
//判斷瀏覽區是否支持canvas
function isSupportCanvas() {
var elem = document.createElement('canvas');
return !!(elem.getContext && elem.getContext('2d'));
}
</script>
</body>
</html>
大家將上述代碼存在一個html文件中,然后通過網頁打開即可。
其中只需要注意
heatmap.setDataSet({
data: points,
max: 1
}
中的data:后面的points是你自己的數據,即在之前定義的json格式經緯度
var points=[
{"lng":"116.32497","lat":"39.96696"},
{"lng":"116.616","lat":"40.053016"},
{"lng":"116.34324","lat":"39.95056"},
{"lng":"116.554131","lat":"39.912131"},
{"lng":"116.3483","lat":"39.83151"},
{"lng":"116.36619","lat":"39.75298"}
];
還有就是max的值(即最紅區域對應的次數值)選取自己覺得合適的,不然太小會幾乎一片紅色,太大幾乎看不到熱力圖顏色。
在這里給大家福利一個將各種格式轉為json文件的小方法:
https://www.bejson.com/json/col2json/
