谷歌Maps Api相当新。我有一个数据数组，我想循环遍历并在地图上绘制。看似相当简单，但我发现的所有多标记教程都相当复杂。
让我们以谷歌网站的数据数组为例:
var locations = [
['Bondi Beach', -33.890542, 151.274856, 4],
['Coogee Beach', -33.923036, 151.259052, 5],
['Cronulla Beach', -34.028249, 151.157507, 3],
['Manly Beach', -33.80010128657071, 151.28747820854187, 2],
['Maroubra Beach', -33.950198, 151.259302, 1]
];
我只是想绘制所有这些点，并在单击时弹出一个infoWindow来显示名称。
当前回答
根据Daniel Vassallo的回答，下面是一个以更简单的方式处理闭包问题的版本。
因为所有的标记都有一个单独的InfoWindow，而且JavaScript并不关心你是否给对象添加了额外的属性，你所需要做的就是给标记的属性添加一个InfoWindow，然后调用InfoWindow本身的.open() !
编辑:有了足够的数据，页面加载可能会花费很多时间，因此与其使用标记构造InfoWindow，不如只在需要时进行构造。注意，用于构造InfoWindow的任何数据都必须作为属性(data)追加到Marker。还要注意，在第一次单击事件之后，infoWindow将作为它的标记的属性持久化，因此浏览器不需要不断地重构。
var locations = [
['Bondi Beach', -33.890542, 151.274856, 4],
['Coogee Beach', -33.923036, 151.259052, 5],
['Cronulla Beach', -34.028249, 151.157507, 3],
['Manly Beach', -33.80010128657071, 151.28747820854187, 2],
['Maroubra Beach', -33.950198, 151.259302, 1]
];
var map = new google.maps.Map(document.getElementById('map'), {
center: new google.maps.LatLng(-33.92, 151.25)
});
for (i = 0; i < locations.length; i++) {
marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[i][1], locations[i][2]),
map: map,
data: {
name: locations[i][0]
}
});
marker.addListener('click', function() {
if(!this.infoWindow) {
this.infoWindow = new google.maps.InfoWindow({
content: this.data.name;
});
}
this.infoWindow.open(map,this);
})
}
其他回答
下面是另一个使用唯一标题和infoWindow文本加载多个标记的示例。使用最新的谷歌映射API V3.11进行测试。
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
<title>Multiple Markers Google Maps</title>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
<script
src="https://maps.googleapis.com/maps/api/js?v=3.11&sensor=false"
type="text/javascript"
></script>
<script type="text/javascript">
// check DOM Ready
$(document).ready(function () {
// execute
(function () {
// map options
var options = {
zoom: 5,
center: new google.maps.LatLng(39.909736, -98.522109), // centered US
mapTypeId: google.maps.MapTypeId.TERRAIN,
mapTypeControl: false,
};
// init map
var map = new google.maps.Map(
document.getElementById('map_canvas'),
options
);
// NY and CA sample Lat / Lng
var southWest = new google.maps.LatLng(40.744656, -74.005966);
var northEast = new google.maps.LatLng(34.052234, -118.243685);
var lngSpan = northEast.lng() - southWest.lng();
var latSpan = northEast.lat() - southWest.lat();
// set multiple marker
for (var i = 0; i < 250; i++) {
// init markers
var marker = new google.maps.Marker({
position: new google.maps.LatLng(
southWest.lat() + latSpan * Math.random(),
southWest.lng() + lngSpan * Math.random()
),
map: map,
title: 'Click Me ' + i,
});
// process multiple info windows
(function (marker, i) {
// add click event
google.maps.event.addListener(marker, 'click', function () {
infowindow = new google.maps.InfoWindow({
content: 'Hello, World!!',
});
infowindow.open(map, marker);
});
})(marker, i);
}
})();
});
</script>
</head>
<body>
<div id="map_canvas" style="width: 800px; height: 500px"></div>
</body>
</html>
250个标记的截图:
它将自动随机化Lat/Lng，使其独一无二。如果你想测试500、1000、xxx标记和性能，这个例子将非常有用。
我想我将把这个放在这里，因为它似乎是那些开始使用谷歌地图API的一个流行的着陆点。在客户端呈现多个标记可能是许多映射应用程序性能下降的原因。很难进行基准测试、修复，在某些情况下甚至很难确定存在问题(由于浏览器实现的差异、客户端可用的硬件、移动设备等等)。
开始解决这个问题的最简单方法是使用标记集群解决方案。其基本思想是将地理上相似的位置分组，并显示点的数量。当用户放大地图时，这些组会展开，显示出下面的单个标记。
也许最简单的实现是markerclusterer库。基本实现如下(在库导入之后):
<script type="text/javascript">
function initialize() {
var center = new google.maps.LatLng(37.4419, -122.1419);
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 3,
center: center,
mapTypeId: google.maps.MapTypeId.ROADMAP
});
var markers = [];
for (var i = 0; i < 100; i++) {
var location = yourData.location[i];
var latLng = new google.maps.LatLng(location.latitude,
location.longitude);
var marker = new google.maps.Marker({
position: latLng
});
markers.push(marker);
}
var markerCluster = new MarkerClusterer({map, markers});
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>
标记不是直接添加到映射中，而是添加到数组中。然后将该数组传递给为您处理复杂计算的库，并将其附加到映射。
这些实现不仅极大地提高了客户端性能，而且在许多情况下，它们还会导致更简单、更整洁的UI，更容易在更大范围内消化数据。
谷歌提供了其他实现。
希望这能帮助到那些刚接触映射的人。
下面是一个Reactjs中多个标记的例子。
下面是映射组件
import React from 'react';
import PropTypes from 'prop-types';
import { Map, InfoWindow, Marker, GoogleApiWrapper } from 'google-maps-react';
const MapContainer = (props) => {
const [mapConfigurations, setMapConfigurations] = useState({
showingInfoWindow: false,
activeMarker: {},
selectedPlace: {}
});
var points = [
{ lat: 42.02, lng: -77.01 },
{ lat: 42.03, lng: -77.02 },
{ lat: 41.03, lng: -77.04 },
{ lat: 42.05, lng: -77.02 }
]
const onMarkerClick = (newProps, marker) => {};
if (!props.google) {
return <div>Loading...</div>;
}
return (
<div className="custom-map-container">
<Map
style={{
minWidth: '200px',
minHeight: '140px',
width: '100%',
height: '100%',
position: 'relative'
}}
initialCenter={{
lat: 42.39,
lng: -72.52
}}
google={props.google}
zoom={16}
>
{points.map(coordinates => (
<Marker
position={{ lat: coordinates.lat, lng: coordinates.lng }}
onClick={onMarkerClick}
icon={{
url: 'https://res.cloudinary.com/mybukka/image/upload/c_scale,r_50,w_30,h_30/v1580550858/yaiwq492u1lwuy2lb9ua.png',
anchor: new google.maps.Point(32, 32), // eslint-disable-line
scaledSize: new google.maps.Size(30, 30) // eslint-disable-line
}}
name={name}
/>))}
<InfoWindow
marker={mapConfigurations.activeMarker}
visible={mapConfigurations.showingInfoWindow}
>
<div>
<h1>{mapConfigurations.selectedPlace.name}</h1>
</div>
</InfoWindow>
</Map>
</div>
);
};
export default GoogleApiWrapper({
apiKey: process.env.GOOGLE_API_KEY,
v: '3'
})(MapContainer);
MapContainer.propTypes = {
google: PropTypes.shape({}).isRequired,
};
来自谷歌Map API示例:
function initialize() {
var myOptions = {
zoom: 10,
center: new google.maps.LatLng(-33.9, 151.2),
mapTypeId: google.maps.MapTypeId.ROADMAP
}
var map = new google.maps.Map(document.getElementById("map_canvas"),
myOptions);
setMarkers(map, beaches);
}
/**
* Data for the markers consisting of a name, a LatLng and a zIndex for
* the order in which these markers should display on top of each
* other.
*/
var beaches = [
['Bondi Beach', -33.890542, 151.274856, 4],
['Coogee Beach', -33.923036, 151.259052, 5],
['Cronulla Beach', -34.028249, 151.157507, 3],
['Manly Beach', -33.80010128657071, 151.28747820854187, 2],
['Maroubra Beach', -33.950198, 151.259302, 1]
];
function setMarkers(map, locations) {
// Add markers to the map
// Marker sizes are expressed as a Size of X,Y
// where the origin of the image (0,0) is located
// in the top left of the image.
// Origins, anchor positions and coordinates of the marker
// increase in the X direction to the right and in
// the Y direction down.
var image = new google.maps.MarkerImage('images/beachflag.png',
// This marker is 20 pixels wide by 32 pixels tall.
new google.maps.Size(20, 32),
// The origin for this image is 0,0.
new google.maps.Point(0,0),
// The anchor for this image is the base of the flagpole at 0,32.
new google.maps.Point(0, 32));
var shadow = new google.maps.MarkerImage('images/beachflag_shadow.png',
// The shadow image is larger in the horizontal dimension
// while the position and offset are the same as for the main image.
new google.maps.Size(37, 32),
new google.maps.Point(0,0),
new google.maps.Point(0, 32));
// Shapes define the clickable region of the icon.
// The type defines an HTML <area> element 'poly' which
// traces out a polygon as a series of X,Y points. The final
// coordinate closes the poly by connecting to the first
// coordinate.
var shape = {
coord: [1, 1, 1, 20, 18, 20, 18 , 1],
type: 'poly'
};
for (var i = 0; i < locations.length; i++) {
var beach = locations[i];
var myLatLng = new google.maps.LatLng(beach[1], beach[2]);
var marker = new google.maps.Marker({
position: myLatLng,
map: map,
shadow: shadow,
icon: image,
shape: shape,
title: beach[0],
zIndex: beach[3]
});
}
}
在程序中添加标记非常简单。你只需要添加以下代码:
var marker = new google.maps.Marker({
position: myLatLng,
map: map,
title: 'Hello World!'
});
当你构造一个标记时，下面的字段是特别重要和经常设置的:
position(必选)指定标识标记初始位置的LatLng。检索LatLng的一种方法是使用地理编码服务。 map(可选)指定放置标记的map。如果在构建标记时没有指定映射，则会创建标记，但不会附加到(或显示在)映射上。稍后可以通过调用标记的setMap()方法添加标记。
注意，在本例中，标题字段设置了将作为工具提示显示的标记标题。
您可以在这里查阅谷歌api文档。
这是在地图中设置一个标记的完整示例。注意，你必须用你的谷歌API密钥替换YOUR_API_KEY:
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Simple markers</title>
<style>
/* Always set the map height explicitly to define the size of the div
* element that contains the map. */
#map {
height: 100%;
}
/* Optional: Makes the sample page fill the window. */
html, body {
height: 100%;
margin: 0;
padding: 0;
}
</style>
</head>
<body>
<div id="map"></div>
<script>
function initMap() {
var myLatLng = {lat: -25.363, lng: 131.044};
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 4,
center: myLatLng
});
var marker = new google.maps.Marker({
position: myLatLng,
map: map,
title: 'Hello World!'
});
}
</script>
<script async defer
src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initMap">
</script>
现在，如果你想在map中绘制数组的标记，你应该这样做:
var locations = [
['Bondi Beach', -33.890542, 151.274856, 4],
['Coogee Beach', -33.923036, 151.259052, 5],
['Cronulla Beach', -34.028249, 151.157507, 3],
['Manly Beach', -33.80010128657071, 151.28747820854187, 2],
['Maroubra Beach', -33.950198, 151.259302, 1]
];
function initMap() {
var myLatLng = {lat: -33.90, lng: 151.16};
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 10,
center: myLatLng
});
var count;
for (count = 0; count < locations.length; count++) {
new google.maps.Marker({
position: new google.maps.LatLng(locations[count][1], locations[count][2]),
map: map,
title: locations[count][0]
});
}
}
这个例子给出了如下结果:
你也可以在你的pin中添加一个infoWindow。你只需要这段代码:
var marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[count][1], locations[count][2]),
map: map
});
marker.info = new google.maps.InfoWindow({
content: 'Hello World!'
});
你可以在这里找到谷歌关于infoWindows的文档。
现在，我们可以在标记像这样“点击”时打开infoWindow:
var marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[count][1], locations[count][2]),
map: map
});
marker.info = new google.maps.InfoWindow({
content: locations [count][0]
});
google.maps.event.addListener(marker, 'click', function() {
// this = marker
var marker_map = this.getMap();
this.info.open(marker_map, this);
// Note: If you call open() without passing a marker, the InfoWindow will use the position specified upon construction through the InfoWindowOptions object literal.
});
注意，您可以在谷歌developer中获得一些关于Listener的文档。
最后，如果用户点击它，我们可以在标记中绘制一个infoWindow。这是我的完整代码:
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Info windows</title>
<style>
/* Always set the map height explicitly to define the size of the div
* element that contains the map. */
#map {
height: 100%;
}
/* Optional: Makes the sample page fill the window. */
html, body {
height: 100%;
margin: 0;
padding: 0;
}
</style>
</head>
<body>
<div id="map"></div>
<script>
var locations = [
['Bondi Beach', -33.890542, 151.274856, 4],
['Coogee Beach', -33.923036, 151.259052, 5],
['Cronulla Beach', -34.028249, 151.157507, 3],
['Manly Beach', -33.80010128657071, 151.28747820854187, 2],
['Maroubra Beach', -33.950198, 151.259302, 1]
];
// When the user clicks the marker, an info window opens.
function initMap() {
var myLatLng = {lat: -33.90, lng: 151.16};
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 10,
center: myLatLng
});
var count=0;
for (count = 0; count < locations.length; count++) {
var marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[count][1], locations[count][2]),
map: map
});
marker.info = new google.maps.InfoWindow({
content: locations [count][0]
});
google.maps.event.addListener(marker, 'click', function() {
// this = marker
var marker_map = this.getMap();
this.info.open(marker_map, this);
// Note: If you call open() without passing a marker, the InfoWindow will use the position specified upon construction through the InfoWindowOptions object literal.
});
}
}
</script>
<script async defer
src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initMap">
</script>
</body>
</html>
通常，你会得到这样的结果:
