leaflet聚合图功能(附源码下载)

前言

leaflet 入门开发系列环境知识点了解：

• leaflet api文档介绍，详细介绍 leaflet 每个类的函数以及属性等等
• leaflet 在线例子
• leaflet 插件，leaflet 的插件库，非常有用

内容概览

leaflet聚合图功能
源代码demo下载

效果图如下：

本篇主要参考leaflet官网聚合效果插件Leaflet.markercluster:https://github.com/Leaflet/Leaflet.markercluster
这个聚合插件具体使用看github地址，那里有详细说明以及例子。

• 模拟数据geojson格式如下：

var geojson = {"type":"FeatureCollection", "features": [
{"type":"Feature","geometry":{"type":"Point","coordinates":[113.16305738210656,23.13667404697526]},"properties":{"Name_CHN":"赤岗塔","StationNum":1,"Status":1}},
{"type":"Feature","geometry":{"type":"Point","coordinates":[113.18383377370634,23.100037587172096]},"properties":{"Name_CHN":"海心沙","StationNum":2,"Status":1}},
……
]};

• 放大地图到一定级别，根据模拟数据的属性值Status不同，对应不同类型的图标：

//根据Status类型不同加载不同图标
var img = './img/projectPoint_HGX.png';
switch(properties.Status) {
case 1:
img = './img/projectPoint_HGX.png';
break;
case 2:
img = './img/projectPoint_JSZT.png';
break;
case 3:
img = './img/projectPoint_XMXZ.png';
break;
case 4:
img = './img/projectPoint_XMZS.png';
break;
}
var myIcon = L.icon({
iconUrl: img,
iconSize: [25, 25],
});
var marker = L.marker(new L.LatLng(coordinate[1], coordinate[0]), {
properties: properties,
icon: myIcon,
});

• 部分核心代码，完整的见源码demo下载

var map = L.map('map');
L.tileLayer('http://map.geoq.cn/ArcGIS/rest/services/ChinaOnlineStreetPurplishBlue/MapServer/tile/{z}/{y}/{x}').addTo(map);
map.setView(L.latLng(22.95186415, 113.90271877), 9); //设置缩放级别及中心点
 
//聚合图
var projectPointLayer = L.markerClusterGroup({
showCoverageOnHover: false,
zoomToBoundsOnClick: true,
chunkedLoading: true,
maxClusterRadius: 40, //默认80
}).addTo(map);
 
if (geojson) {
addProjectClusterLayers(geojson, projectPointLayer);
projectPointLayer.on("click", function (e) {
e.layer.unbindPopup();
var elements = getProjectPopupContent(
e.layer.options.properties
);
e.layer.bindPopup(elements[0]).openPopup(e.latlng);
});
}
 
/*
* 点单击内容函数
*/
function getProjectPopupContent(item) {
const { toPopupItemStr } = this;
const me = this;
// 内容及单击事件
const elements = $(
`

${toPopupItemStr("名称", item.Name_CHN)}
${toPopupItemStr("站口个数", item.StationNum)}
详情 
`
);
return elements;
}
 
// 转为popup项
function toPopupItemStr(name, value){
return value ? `${name}：${value}
` : "";
};
 
/*
* 加载聚合图层
*/
function addProjectClusterLayers(geojson, clusterlayer) {
var markerList = [];
if (geojson.features.length > 0) {
for (var i = 0; i < geojson.features.length; i++) {
if (geojson.features[i].geometry) {
var properties = geojson.features[i].properties;
var coordinate = geojson.features[i].geometry.coordinates;
//根据Status类型不同加载不同图标
var img = './img/projectPoint_HGX.png';
switch(properties.Status) {
case 1:
img = './img/projectPoint_HGX.png';
break;
case 2:
img = './img/projectPoint_JSZT.png';
break;
case 3:
img = './img/projectPoint_XMXZ.png';
break;
case 4:
img = './img/projectPoint_XMZS.png';
break;
}
var myIcon = L.icon({
iconUrl: img,
iconSize: [25, 25],
});
var marker = L.marker(new L.LatLng(coordinate[1], coordinate[0]), {
properties: properties,
icon: myIcon,
});
markerList.push(marker);
}
}
}
clusterlayer.addLayers(markerList);
};

完整demo源码见小专栏文章尾部：小专栏

文章尾部提供源代码下载，对本专栏感兴趣的话，可以关注一波