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

下面是一个几乎完整的示例javascript函数,它允许在JSONObject中定义多个标记。

它将只显示在地图边界内的标记。

这很重要,这样你就不用做额外的工作了。

你也可以设置一个标记的限制,这样你就不会显示一个极端数量的标记(如果有可能在你的使用);

如果地图中心的变化不超过500米,就不会显示标记。 这很重要,因为如果用户单击标记并在此过程中意外地拖动了地图,您不希望地图重新加载标记。

我将这个函数附加到地图的空闲事件侦听器,因此标记只在地图空闲时显示,并在不同的事件后重新显示标记。

活动屏幕截图 在信息窗口中显示更多内容的屏幕截图有一个小变化。 粘贴自pastbin.com

<script src=“//pastebin.com/embed_js/uWAbRxfg”></script>

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。

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 &lt;area&gt; 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]
    });
  }
}

已接受的答案,在ES6中重写:

$(document).ready(() => {
  const mapEl = $('#our_map').get(0); // OR document.getElementById('our_map');

  // Display a map on the page
  const map = new google.maps.Map(mapEl, { mapTypeId: 'roadmap' });

  const buildings = [
    {
      title: 'London Eye, London', 
      coordinates: [51.503454, -0.119562],
      info: 'carousel'
    },
    {
      title: 'Palace of Westminster, London', 
      coordinates: [51.499633, -0.124755],
      info: 'palace'
    }
  ];

  placeBuildingsOnMap(buildings, map);
});


const placeBuildingsOnMap = (buildings, map) => {
  // Loop through our array of buildings & place each one on the map  
  const bounds = new google.maps.LatLngBounds();
  buildings.forEach((building) => {
    const position = { lat: building.coordinates[0], lng: building.coordinates[1] }
    // Stretch our bounds to the newly found marker position
    bounds.extend(position);

    const marker = new google.maps.Marker({
      position: position,
      map: map,
      title: building.title
    });

    const infoWindow = new google.maps.InfoWindow();
    // Allow each marker to have an info window
    google.maps.event.addListener(marker, 'click', () => {
      infoWindow.setContent(building.info);
      infoWindow.open(map, marker);
    })

    // Automatically center the map fitting all markers on the screen
    map.fitBounds(bounds);
  })
})

这是我写的另一个版本来节省地图的空间,它将infowindow指针放在标记的实际纬度和长度上,而在显示infowindow时暂时隐藏标记。

它还取消了标准的“标记”分配,并加快了速度 通过直接将新标记分配给标记创建中的标记数组进行处理。但是请注意,标记和信息窗口都添加了额外的属性,所以这种方法有点不合常规……但那是我!

在这些信息窗口问题中从未提到,标准的信息窗口不是放在标记点的lat和lng上,而是放在标记图像的顶部。标记可见性必须隐藏,否则Maps API将再次将信息窗口锚推回标记图像的顶部。

对“标记”数组中的标记的引用在标记声明后立即创建,用于以后可能需要的任何额外处理任务(隐藏/显示,抓取坐标等)。这样就省去了将标记对象赋值给'marker'的额外步骤,然后将'marker'推到标记数组中…在我的书里有很多不必要的处理。

不管怎样,对信息窗口有不同的看法,希望它能帮助你了解和激励你。

    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;
    var markers = [];

    function init(){
      map = new google.maps.Map(document.getElementById('map_canvas'), {
        zoom: 10,
        center: new google.maps.LatLng(-33.92, 151.25),
        mapTypeId: google.maps.MapTypeId.ROADMAP
      });

      var num_markers = locations.length;
      for (var i = 0; i < num_markers; i++) {  
        markers[i] = new google.maps.Marker({
          position: {lat:locations[i][1], lng:locations[i][2]},
          map: map,
          html: locations[i][0],
          id: i,
        });

        google.maps.event.addListener(markers[i], 'click', function(){
          var infowindow = new google.maps.InfoWindow({
            id: this.id,
            content:this.html,
            position:this.getPosition()
          });
          google.maps.event.addListenerOnce(infowindow, 'closeclick', function(){
            markers[this.id].setVisible(true);
          });
          this.setVisible(false);
          infowindow.open(map);
        });
      }
    }

google.maps.event.addDomListener(window, 'load', init);

这是一个工作的JSFiddle

额外的注意 您将注意到在给定的谷歌示例数据中,'locations'数组中的第四个位置是一个数字。在这个例子中,你也可以使用这个值作为标记id来代替当前循环的值,这样…

var num_markers = locations.length;
for (var i = 0; i < num_markers; i++) {  
  markers[i] = new google.maps.Marker({
    position: {lat:locations[i][1], lng:locations[i][2]},
    map: map,
    html: locations[i][0],
    id: locations[i][3],
  });
};

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。