將標記設計為可點擊且易於讀取

您可以啟用點擊事件處理、為螢幕閱讀器新增描述性文字，以及調整標記比例，讓標記更易於讀取。

  • 如果標記可點選 (或拖曳)，就能回應鍵盤和滑鼠的輸入動作。
  • 螢幕閱讀器可閱讀 title 選項中指定的文字，並會在使用者將滑鼠游標懸停在標記上時顯示。
  • 放大標記會降低在所有裝置上 (特別是觸控螢幕裝置) 與標記互動所需的精準度，使用上更為方便。預設標記符合 WCAG AA 最小尺寸標準，但如果開發人員想要遵循 WCAG AAA 目標尺寸標準，就需要放大標記。

請參閱「自訂基本標記」，瞭解如何變更標記比例、新增標題文字等。

以下地圖範例含有五個可點選且可聚焦的標記，這些標記包含標題文字，且已設為 1.5 倍的比例：

如要使用鍵盤瀏覽標記：

  1. 使用 Tab 鍵可將焦點移至第一個標記，如果一張地圖上有多個標記，使用方向鍵即可輪轉切換標記。
  2. 如果標記可點選，按下 Enter 鍵即可執行「點選」動作。如要開啟標記內含的資訊視窗，您可以點選標記，或是按下 Enter 鍵或空格鍵。資訊視窗關閉後，焦點就會回到相關標記。
  3. 再次按下 Tab 鍵，即可繼續在其他地圖控制項之間移動。

將標記設計為可點擊

本節將說明如何讓標記回應點擊事件。如要將標記設計為可點選，請按照下列步驟操作：

  • 將 gmpClickable 屬性設為 true。

TypeScript

const marker = new AdvancedMarkerElement({
    position,
    map,
    title: `${i + 1}. ${title}`,
    content: pin.element,
    gmpClickable: true,
});
index.ts

JavaScript

const marker = new AdvancedMarkerElement({
  position,
  map,
  title: `${i + 1}. ${title}`,
  content: pin.element,
  gmpClickable: true,
});

index.js

  • 新增點擊事件監聽器，回應使用者輸入內容。

TypeScript

// Add a click listener for each marker, and set up the info window.
marker.addListener('click', ({ domEvent, latLng }) => {
    const { target } = domEvent;
    infoWindow.close();
    infoWindow.setContent(marker.title);
    infoWindow.open(marker.map, marker);
});
index.ts

JavaScript

// Add a click listener for each marker, and set up the info window.
marker.addListener("click", ({ domEvent, latLng }) => {
  const { target } = domEvent;

  infoWindow.close();
  infoWindow.setContent(marker.title);
  infoWindow.open(marker.map, marker);
});
index.js

  • 如要將標記復原為不可點選，請呼叫 removeListener 來移除點擊事件監聽器：

    // Remove the listener.
google.maps.event.removeListener(clickListener);

如要進一步改善無障礙功能，請採取下列做法：

  • 使用 AdvancedMarkerElement.title 選項設定標記的說明文字。
  • 使用 PinElement 的 scale 屬性增加標記比例。

完整程式碼範例

查看完整原始碼範例

TypeScript

async function initMap() {
    // Request needed libraries.
    const { Map, InfoWindow } = await google.maps.importLibrary("maps") as google.maps.MapsLibrary;
    const { AdvancedMarkerElement, PinElement } = await google.maps.importLibrary("marker") as google.maps.MarkerLibrary;

    const map = new Map(document.getElementById("map") as HTMLElement, {
        zoom: 12,
        center: { lat: 34.84555, lng: -111.8035 },
        mapId: '4504f8b37365c3d0',
    });

    // Set LatLng and title text for the markers. The first marker (Boynton Pass)
    // receives the initial focus when tab is pressed. Use arrow keys to move
    // between markers; press tab again to cycle through the map controls.
    const tourStops = [
        {
            position: { lat: 34.8791806, lng: -111.8265049 }, 
            title: "Boynton Pass"
        },
        {
            position: { lat: 34.8559195, lng: -111.7988186 }, 
            title: "Airport Mesa"
        },
        {
            position: { lat: 34.832149, lng: -111.7695277 }, 
            title: "Chapel of the Holy Cross"
        },
        {
            position: { lat: 34.823736, lng: -111.8001857 }, 
            title: "Red Rock Crossing"
        },
        {
            position: { lat: 34.800326, lng: -111.7665047 }, 
            title: "Bell Rock"
        },
    ];

    // Create an info window to share between markers.
    const infoWindow = new InfoWindow();

    // Create the markers.
    tourStops.forEach(({position, title}, i) => {
        const pin = new PinElement({
            glyph: `${i + 1}`,
            scale: 1.5,
        });
        const marker = new AdvancedMarkerElement({
            position,
            map,
            title: `${i + 1}. ${title}`,
            content: pin.element,
            gmpClickable: true,
        });
        // Add a click listener for each marker, and set up the info window.
        marker.addListener('click', ({ domEvent, latLng }) => {
            const { target } = domEvent;
            infoWindow.close();
            infoWindow.setContent(marker.title);
            infoWindow.open(marker.map, marker);
        });
    });
}

initMap();
index.ts

JavaScript

async function initMap() {
  // Request needed libraries.
  const { Map, InfoWindow } = await google.maps.importLibrary("maps");
  const { AdvancedMarkerElement, PinElement } = await google.maps.importLibrary(
    "marker",
  );
  const map = new Map(document.getElementById("map"), {
    zoom: 12,
    center: { lat: 34.84555, lng: -111.8035 },
    mapId: "4504f8b37365c3d0",
  });
  // Set LatLng and title text for the markers. The first marker (Boynton Pass)
  // receives the initial focus when tab is pressed. Use arrow keys to move
  // between markers; press tab again to cycle through the map controls.
  const tourStops = [
    {
      position: { lat: 34.8791806, lng: -111.8265049 },
      title: "Boynton Pass",
    },
    {
      position: { lat: 34.8559195, lng: -111.7988186 },
      title: "Airport Mesa",
    },
    {
      position: { lat: 34.832149, lng: -111.7695277 },
      title: "Chapel of the Holy Cross",
    },
    {
      position: { lat: 34.823736, lng: -111.8001857 },
      title: "Red Rock Crossing",
    },
    {
      position: { lat: 34.800326, lng: -111.7665047 },
      title: "Bell Rock",
    },
  ];
  // Create an info window to share between markers.
  const infoWindow = new InfoWindow();

  // Create the markers.
  tourStops.forEach(({ position, title }, i) => {
    const pin = new PinElement({
      glyph: `${i + 1}`,
      scale: 1.5,
    });
    const marker = new AdvancedMarkerElement({
      position,
      map,
      title: `${i + 1}. ${title}`,
      content: pin.element,
      gmpClickable: true,
    });

    // Add a click listener for each marker, and set up the info window.
    marker.addListener("click", ({ domEvent, latLng }) => {
      const { target } = domEvent;

      infoWindow.close();
      infoWindow.setContent(marker.title);
      infoWindow.open(marker.map, marker);
    });
  });
}

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;
}

style.css

HTML

<html>
  <head>
    <title>Advanced Marker Accessibility</title>

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

    <!-- prettier-ignore -->
    <script>(g=>{var h,a,k,p="The Google Maps JavaScript API",c="google",l="importLibrary",q="__ib__",m=document,b=window;b=b[c]||(b[c]={});var d=b.maps||(b.maps={}),r=new Set,e=new URLSearchParams,u=()=>h||(h=new Promise(async(f,n)=>{await (a=m.createElement("script"));e.set("libraries",[...r]+"");for(k in g)e.set(k.replace(/[A-Z]/g,t=>"_"+t[0].toLowerCase()),g[k]);e.set("callback",c+".maps."+q);a.src=`https://maps.${c}apis.com/maps/api/js?`+e;d[q]=f;a.onerror=()=>h=n(Error(p+" could not load."));a.nonce=m.querySelector("script[nonce]")?.nonce||"";m.head.append(a)}));d[l]?console.warn(p+" only loads once. Ignoring:",g):d[l]=(f,...n)=>r.add(f)&&u().then(()=>d[l](f,...n))})
        ({key: "AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg", v: "beta"});</script>
  </body>
</html>
index.html

測試範例