自訂 Google 地圖：自訂圖例

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瞭解如何透過本教學課程在 Google 地圖上建立圖例。圖例一般用來說明地圖上的符號和標記。您可以使用自訂控制項的定位功能建立圖例。

下方地圖包含圖例，提供地圖上三種不同自訂標記的相關資訊。

下方是您在本教學課程中建立地圖和圖例時所需的完整程式碼。

TypeScript

let map: google.maps.Map;

function initMap(): void {
  map = new google.maps.Map(document.getElementById("map") as HTMLElement, {
    zoom: 16,
    center: new google.maps.LatLng(-33.91722, 151.23064),
    mapTypeId: "roadmap",
  });

  const iconBase = "https://maps.google.com/mapfiles/kml/shapes/";
  const icons: Record<string, any> = {
    parking: {
      name: "Parking",
      icon: iconBase + "parking_lot_maps.png",
    },
    library: {
      name: "Library",
      icon: iconBase + "library_maps.png",
    },
    info: {
      name: "Info",
      icon: iconBase + "info-i_maps.png",
    },
  };

  const features = [
    {
      position: new google.maps.LatLng(-33.91721, 151.2263),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91539, 151.2282),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91747, 151.22912),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.9191, 151.22907),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91725, 151.23011),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91872, 151.23089),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91784, 151.23094),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91682, 151.23149),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.9179, 151.23463),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91666, 151.23468),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.916988, 151.23364),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91662347903106, 151.22879464019775),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.916365282092855, 151.22937399734496),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91665018901448, 151.2282474695587),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.919543720969806, 151.23112279762267),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91608037421864, 151.23288232673644),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91851096391805, 151.2344058214569),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91818154739766, 151.2346203981781),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91727341958453, 151.23348314155578),
      type: "library",
    },
  ];

  features.forEach((feature) => {
    new google.maps.Marker({
      position: feature.position,
      icon: icons[feature.type].icon,
      map: map,
    });
  });

  const legend = document.getElementById("legend") as HTMLElement;

  for (const key in icons) {
    const type = icons[key];
    const name = type.name;
    const icon = type.icon;
    const div = document.createElement("div");

    div.innerHTML = '<img src="' + icon + '"> ' + name;
    legend.appendChild(div);
  }

  map.controls[google.maps.ControlPosition.RIGHT_BOTTOM].push(legend);
}

declare global {
  interface Window {
    initMap: () => void;
  }
}
window.initMap = initMap;
index.ts

JavaScript

let map;

function initMap() {
  map = new google.maps.Map(document.getElementById("map"), {
    zoom: 16,
    center: new google.maps.LatLng(-33.91722, 151.23064),
    mapTypeId: "roadmap",
  });

  const iconBase = "https://maps.google.com/mapfiles/kml/shapes/";
  const icons = {
    parking: {
      name: "Parking",
      icon: iconBase + "parking_lot_maps.png",
    },
    library: {
      name: "Library",
      icon: iconBase + "library_maps.png",
    },
    info: {
      name: "Info",
      icon: iconBase + "info-i_maps.png",
    },
  };
  const features = [
    {
      position: new google.maps.LatLng(-33.91721, 151.2263),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91539, 151.2282),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91747, 151.22912),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.9191, 151.22907),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91725, 151.23011),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91872, 151.23089),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91784, 151.23094),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91682, 151.23149),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.9179, 151.23463),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91666, 151.23468),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.916988, 151.23364),
      type: "info",
    },
    {
      position: new google.maps.LatLng(-33.91662347903106, 151.22879464019775),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.916365282092855, 151.22937399734496),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91665018901448, 151.2282474695587),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.919543720969806, 151.23112279762267),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91608037421864, 151.23288232673644),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91851096391805, 151.2344058214569),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91818154739766, 151.2346203981781),
      type: "parking",
    },
    {
      position: new google.maps.LatLng(-33.91727341958453, 151.23348314155578),
      type: "library",
    },
  ];

  features.forEach((feature) => {
    new google.maps.Marker({
      position: feature.position,
      icon: icons[feature.type].icon,
      map: map,
    });
  });

  const legend = document.getElementById("legend");

  for (const key in icons) {
    const type = icons[key];
    const name = type.name;
    const icon = type.icon;
    const div = document.createElement("div");

    div.innerHTML = '<img src="' + icon + '"> ' + name;
    legend.appendChild(div);
  }

  map.controls[google.maps.ControlPosition.RIGHT_BOTTOM].push(legend);
}

window.initMap = initMap;
index.js

CSS

/* 
 * 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;
}

#legend {
  font-family: Arial, sans-serif;
  background: #fff;
  padding: 10px;
  margin: 10px;
  border: 3px solid #000;
}

#legend h3 {
  margin-top: 0;
}

#legend img {
  vertical-align: middle;
}

style.css

HTML

<html>
  <head>
    <title>Custom Legend</title>

    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script type="module" src="./index.js"></script>
  </head>
  <body>
    <div id="map"></div>
    <div id="legend"><h3>Legend</h3></div>

    <!-- 
      The `defer` attribute causes the script to execute after the full HTML
      document has been parsed. For non-blocking uses, avoiding race conditions,
      and consistent behavior across browsers, consider loading using Promises. See
      https://developers.google.com/maps/documentation/javascript/load-maps-js-api
      for more information.
      -->
    <script
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg&callback=initMap&v=weekly"
      defer
    ></script>
  </body>
</html>
index.html

測試範例

以下各節說明建立圖例的主要步驟。

建立圖例容器

下表說明自訂圖例的程式碼。

程式碼與說明 
<div id="legend"><h3>Legend</h3></div>
建立 div 來存放內容。
在 div 中加入第三 (3) 層標題。		 
map.controls[google.maps.ControlPosition.RIGHT_BOTTOM].push
(document.getElementById('legend'));
新增控制項位置，將 div 放置在地圖右下角。
請參閱更多控制項位置選項。		 
<style>
  #legend {
    font-family: Arial, sans-serif;
    background: #fff;
    padding: 10px;
    margin: 10px;
    border: 3px solid #000;
  }
</style>
使用 CSS 設定圖例控制項的樣式。

新增圖例內容

使用現有的標記樣式定義來填入圖例。

var legend = document.getElementById('legend');
for (var style in styles) {
  var name = style.name;
  var icon = style.icon;
  var div = document.createElement('div');
  div.innerHTML = '<img src="' + icon + '"> ' + name;
  legend.appendChild(div);
}