这是我的剧本,我目前的传单很糟糕,加载我的标记需要花费大量时间,但我一次只玩200-500似乎无法找到原因。
将标记从API中提取并存储到数组中,然后在点击地图上的某个部分时将其绘制到地图上,在实时演示中查看自己,它可以正常工作直到加载标记然后在缩放时开始滞后很多
如果有人为我提供解决方案,我将非常感激,因为我打算拥有比现在更多的标记。
var postcode;
var police_api_dates = [
"&date=2017-03",
];
var completed_requests = 0;
var police_api_base_url = "https://data.police.uk/api/crimes-street/all-crime?poly=";
var crimes = [];
var count = 0;
var mymap = L.map('map').setView([53.7983587, -1.6191674], 11);
mymap.createPane('labels');
mymap.getPane('labels').style.zIndex = 650;
mymap.getPane('labels').style.pointerEvents = 'none';
var positron = L.tileLayer('http://{s}.basemaps.cartocdn.com/light_nolabels/{z}/{x}/{y}.png', {
attribution: '©OpenStreetMap, ©CartoDB'
}).addTo(mymap);
var positronLabels = L.tileLayer('http://{s}.basemaps.cartocdn.com/light_only_labels/{z}/{x}/{y}.png', {
attribution: '©OpenStreetMap, ©CartoDB',
pane: 'labels'
}).addTo(mymap);
L.tileLayer('https://api.mapbox.com/styles/v1/adam97x/cjavcj1680vgz2sqshn70q5pg/tiles/256/{z}/{x}/{y}?access_token=pk.eyJ1IjoiYWRhbTk3eCIsImEiOiJjamF2Y2k1NmswYzhuMnZtazlpNXU2NDExIn0.RifBBI5nelL-4d21mkn7Wg', {
maxZoom: 18,
attribution: 'Map data © <a href="http://openstreetmap.org">OpenStreetMap</a> contributors, ' +
'<a href="http://creativecommons.org/licenses/by-sa/2.0/">CC-BY-SA</a>, ' +
'Imagery © <a href="http://mapbox.com">Mapbox</a>',
id: 'mapbox.streets'
}).addTo(mymap);
// control that shows state info on hover
var info = L.control();
info.onAdd = function (mymap) {
this._div = L.DomUtil.create('div', 'info');
this.update();
return this._div;
};
info.update = function (properties) {
this._div.innerHTML = '<h4>Highlighted Postcode</h4>' + (properties ?
'<b> Postcode: ' + properties.Name
: 'Hover over a state');
};
info.addTo(mymap);
function style(feature) {
return {
fillColor: 'grey',
weight: 2,
opacity: 1,
color: 'white',
dashArray: '3',
fillOpacity: 0.5
};
}
L.geoJson(statesdata, {style: style}).addTo(mymap);
function highlightFeature(e) {
var layer = e.target;
layer.setStyle({
weight: 5,
opacity: 1,
color: '#000',
dashArray: '',
fillOpacity: 0.7
});
if (!L.Browser.ie && !L.Browser.opera && !L.Browser.edge) {
layer.bringToFront();
}
info.update(layer.feature.properties);
postcode = layer.feature.properties.Name.substr(2)-1;
console.log(postcode);
}
/*global statesdata*/
var geojson;
function resetHighlight(e) {
geojson.resetStyle(e.target);
info.update();
}
function zoomFeature(e) {
mymap.fitBounds(e.target.getBounds());
var colonString = statesdata
.features[postcode]
.geometry
.coordinates[0]
.map(pair => pair.reverse().join())
.join(':');
for (var a = 0; a < 1; a++){
var request = police_api_base_url + colonString + police_api_dates[a]
get_JSON(request, JSON_callback);
}
}
function onEachFeature(feature, layer) {
layer.on({
mouseover: highlightFeature,
mouseout: resetHighlight,
click: zoomFeature
});
}
geojson = L.geoJson(statesdata, {
style: style,
onEachFeature: onEachFeature
}).addTo(mymap);
geojson.eachLayer(function (layer) {
layer.bindPopup(layer.feature.properties.Name);
});
function JSON_callback(data){
completed_requests++;
var data_len = data.length;
if (data[0] != undefined){
for (var i = 0; i < data_len; i++){
cat = data[i]["category"];
lat = data[i]["location"]["latitude"];
lng = data[i]["location"]["longitude"];
if (cat in crimes) {
crimes[cat]++;
} else {
crimes[cat] = 1;
}
create_marker(lat, lng);
}
}
if (completed_requests == 1){
console.log("Requests done");
console.log(crimes);
}
}
function create_crime_markers(lat, lng, cat){
show_by_id("num_of_crimes_load_img");
show_by_id("popular_crime_load_img");
completed_requests = 0;
num_of_crimes = 0;
crimes = {};;
for (var a = 0; a < 1; a++){
var request = police_api_base_url + lat + "&lng=" + lng + police_api_dates[a]
get_JSON(request, JSON_callback);
}
}
var current_lat_lng = [];
function create_marker(lat, lng, title){
current_lat_lng.push(lat, lng, cat);
chunksize = 3;
var chunks = [];
current_lat_lng.forEach((item)=>{
if(!chunks.length || chunks[chunks.length-1].length == chunksize)
chunks.push([]);
chunks[chunks.length-1].push(item);
});
var markers = L.markerClusterGroup({
chunkedloading: true,
spiderfyOnMaxZoom: true,
showCoverageOnHover: false,
zoomToBoundsOnClick: true,
spiderfyDistanceMultiplier: 2.4
});
var markerList = [];
for (var f = 0; f < chunks.length; f++) {
var marker = new L.circleMarker([chunks[f][0],chunks[f][1]])
markerList.push(marker);
}
markers.addLayers(markerList);
mymap.addLayer(markers);
}
&#13;
body { margin:0; padding:0; }
#map { position:absolute; top:0; bottom:0; width:100%; }
.info { padding: 6px 8px; font: 14px/16px Arial, Helvetica, sans-serif; background: white; background: rgba(255,255,255,0.8); box-shadow: 0 0 15px rgba(0,0,0,0.2); border-radius: 5px; } .info h4 { margin: 0 0 5px; color: #777; }
&#13;
<html>
<head>
<meta charset=utf-8 />
<title>KML Data</title>
<meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
<link rel="stylesheet" href="https://unpkg.com/leaflet@1.2.0/dist/leaflet.css" />
<link rel="stylesheet" href="https://unpkg.com/leaflet.markercluster@1.2.0/dist/MarkerCluster.Default.css" />
<script src="https://unpkg.com/leaflet@1.2.0/dist/leaflet.js"></script>
<script type="text/javascript" src="https://project-adam97.c9users.io/asset/bd.js"></script>
<script src="https://project-adam97.c9users.io/asset/requests.js"></script>
</head>
<body>
<script> src='https://api.mapbox.com/mapbox.js/plugins/leaflet-omnivore/v0.2.0/leaflet-omnivore.min.js'></script>
<script src="https://unpkg.com/leaflet.markercluster@1.2.0/dist/leaflet.markercluster.js"></script>
<div id='map'></div>
</body>
</html>
&#13;