التعامل مع أحداث الماوس

اختَر النظام الأساسي: iOS JavaScript

نظرة عامة

يمكنك إنشاء طبقة عناصر تستجيب لأحداث mousemove وclick، واستخدِمها لعرض معلومات حول الحدود التي تم النقر عليها. وتشمل هذه المعلومات رقم التعريف والاسم المعروض ونوع الميزة. يوضّح المثال التالي على الخريطة حدود المنطقة الإدارية من المستوى 2، وتحتوي على رمز معالجة الأحداث الذي يُصمِّم المضلّعات استنادًا إلى تفاعل المستخدم (يغير mousemove سُمك الحدود، ويظلّل click لون الخلفية ويتسبب في عرض نافذة معلومات).

تفعيل أحداث طبقات العناصر

اتّخِذ الخطوات التالية لتفعيل الأحداث على إحدى طبقات العناصر:

  1. يمكنك تسجيل طبقة ميزة لإشعارات الأحداث من خلال استدعاء الدالة addListener() في طبقة العناصر لكل حدث تريد تسجيله. في هذا المثال، تحصل الخريطة أيضًا على مستمع.

    TypeScript

    // Add the feature layer.
    //@ts-ignore
    featureLayer = map.getFeatureLayer('ADMINISTRATIVE_AREA_LEVEL_2');
    
    // Add the event listeners for the feature layer.
    featureLayer.addListener('click', handleClick);
    featureLayer.addListener('mousemove', handleMouseMove);
    
    // Map event listener.
    map.addListener('mousemove', () => {
      // If the map gets a mousemove, that means there are no feature layers
      // with listeners registered under the mouse, so we clear the last
      // interacted feature ids.
      if (lastInteractedFeatureIds?.length) {
        lastInteractedFeatureIds = [];
        featureLayer.style = applyStyle;
      }
    });

    JavaScript

    // Add the feature layer.
    //@ts-ignore
    featureLayer = map.getFeatureLayer("ADMINISTRATIVE_AREA_LEVEL_2");
    // Add the event listeners for the feature layer.
    featureLayer.addListener("click", handleClick);
    featureLayer.addListener("mousemove", handleMouseMove);
    // Map event listener.
    map.addListener("mousemove", () => {
      // If the map gets a mousemove, that means there are no feature layers
      // with listeners registered under the mouse, so we clear the last
      // interacted feature ids.
      if (lastInteractedFeatureIds?.length) {
        lastInteractedFeatureIds = [];
        featureLayer.style = applyStyle;
      }
    });

  2. أضِف رمز معالج الأحداث لتصميم المضلّع المحدّد استنادًا إلى نوع التفاعل.

    TypeScript

    function handleClick(/* MouseEvent */ e) {
      lastClickedFeatureIds = e.features.map(f => f.placeId);
      lastInteractedFeatureIds = [];
      featureLayer.style = applyStyle;
      createInfoWindow(e);
    }
    
    function handleMouseMove(/* MouseEvent */ e) {
      lastInteractedFeatureIds = e.features.map(f => f.placeId);
      featureLayer.style = applyStyle;
    }

    JavaScript

    function handleClick(/* MouseEvent */ e) {
      lastClickedFeatureIds = e.features.map((f) => f.placeId);
      lastInteractedFeatureIds = [];
      featureLayer.style = applyStyle;
      createInfoWindow(e);
    }
    
    function handleMouseMove(/* MouseEvent */ e) {
      lastInteractedFeatureIds = e.features.map((f) => f.placeId);
      featureLayer.style = applyStyle;
    }
    

  3. استخدِم دالة نمط الميزة لتطبيق الأنماط. تطبق دالة نمط الميزة الموضحة هنا النمط بشكل مشروط بناءً على نوع التفاعل. يتم هنا تحديد ثلاثة أنماط: أحدها لجعل الحد بخط غامق على mousemove، ونمط لتغيير الخلفية وعرض نافذة معلومات على click، والنمط التلقائي.

    TypeScript

    // Define styles.
    // Stroke and fill with minimum opacity value.
    const styleDefault = {
      strokeColor: '#810FCB',
      strokeOpacity: 1.0,
      strokeWeight: 2.0,
      fillColor: 'white',
      fillOpacity: 0.1,  // Polygons must be visible to receive events.
    };
    // Style for the clicked polygon.
    const styleClicked = {
      ...styleDefault,
      fillColor: '#810FCB',
      fillOpacity: 0.5,
    };
    // Style for polygon on mouse move.
    const styleMouseMove = {
      ...styleDefault,
      strokeWeight: 4.0,
    };
    
    // Apply styles using a feature style function.
    function applyStyle(/* FeatureStyleFunctionOptions */ params) {
      const placeId = params.feature.placeId;
      //@ts-ignore
      if (lastClickedFeatureIds.includes(placeId)) {
        return styleClicked;
      }
      //@ts-ignore
      if (lastInteractedFeatureIds.includes(placeId)) {
        return styleMouseMove;
      }
      return styleDefault;
    }

    JavaScript

    // Define styles.
    // Stroke and fill with minimum opacity value.
    const styleDefault = {
      strokeColor: "#810FCB",
      strokeOpacity: 1.0,
      strokeWeight: 2.0,
      fillColor: "white",
      fillOpacity: 0.1, // Polygons must be visible to receive events.
    };
    // Style for the clicked polygon.
    const styleClicked = {
      ...styleDefault,
      fillColor: "#810FCB",
      fillOpacity: 0.5,
    };
    // Style for polygon on mouse move.
    const styleMouseMove = {
      ...styleDefault,
      strokeWeight: 4.0,
    };
    
    // Apply styles using a feature style function.
    function applyStyle(/* FeatureStyleFunctionOptions */ params) {
      const placeId = params.feature.placeId;
    
      //@ts-ignore
      if (lastClickedFeatureIds.includes(placeId)) {
        return styleClicked;
      }
    
      //@ts-ignore
      if (lastInteractedFeatureIds.includes(placeId)) {
        return styleMouseMove;
      }
      return styleDefault;
    }
    

إكمال نموذج الرمز

TypeScript

let map: google.maps.Map;
let featureLayer;
let infoWindow;
let lastInteractedFeatureIds = [];
let lastClickedFeatureIds = [];

function handleClick(/* MouseEvent */ e) {
  lastClickedFeatureIds = e.features.map(f => f.placeId);
  lastInteractedFeatureIds = [];
  featureLayer.style = applyStyle;
  createInfoWindow(e);
}

function handleMouseMove(/* MouseEvent */ e) {
  lastInteractedFeatureIds = e.features.map(f => f.placeId);
  featureLayer.style = applyStyle;
}

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

  map = new Map(document.getElementById('map') as HTMLElement, {
    center: {lat: 39.23, lng: -105.73},
    zoom: 8,
    // In the cloud console, configure your Map ID with a style that enables the
    // 'Administrative Area Level 2' Data Driven Styling type.
    mapId: 'a3efe1c035bad51b', // Substitute your own map ID.
    mapTypeControl: false,
  });

  // Add the feature layer.
  //@ts-ignore
  featureLayer = map.getFeatureLayer('ADMINISTRATIVE_AREA_LEVEL_2');

  // Add the event listeners for the feature layer.
  featureLayer.addListener('click', handleClick);
  featureLayer.addListener('mousemove', handleMouseMove);

  // Map event listener.
  map.addListener('mousemove', () => {
    // If the map gets a mousemove, that means there are no feature layers
    // with listeners registered under the mouse, so we clear the last
    // interacted feature ids.
    if (lastInteractedFeatureIds?.length) {
      lastInteractedFeatureIds = [];
      featureLayer.style = applyStyle;
    }
  });

  // Create the infowindow.
  infoWindow = new InfoWindow({});
  // Apply style on load, to enable clicking.
  featureLayer.style = applyStyle;
}

// Helper function for the infowindow.
async function createInfoWindow(event) {
  let feature = event.features[0];
  if (!feature.placeId) return;

  // Update the infowindow.
  const place = await feature.fetchPlace();
  let content =
      '<span style="font-size:small">Display name: ' + place.displayName +
      '<br/> Place ID: ' + feature.placeId +
      '<br/> Feature type: ' + feature.featureType + '</span>';

  updateInfoWindow(content, event.latLng);
}

// Define styles.
// Stroke and fill with minimum opacity value.
const styleDefault = {
  strokeColor: '#810FCB',
  strokeOpacity: 1.0,
  strokeWeight: 2.0,
  fillColor: 'white',
  fillOpacity: 0.1,  // Polygons must be visible to receive events.
};
// Style for the clicked polygon.
const styleClicked = {
  ...styleDefault,
  fillColor: '#810FCB',
  fillOpacity: 0.5,
};
// Style for polygon on mouse move.
const styleMouseMove = {
  ...styleDefault,
  strokeWeight: 4.0,
};

// Apply styles using a feature style function.
function applyStyle(/* FeatureStyleFunctionOptions */ params) {
  const placeId = params.feature.placeId;
  //@ts-ignore
  if (lastClickedFeatureIds.includes(placeId)) {
    return styleClicked;
  }
  //@ts-ignore
  if (lastInteractedFeatureIds.includes(placeId)) {
    return styleMouseMove;
  }
  return styleDefault;
}

// Helper function to create an info window.
function updateInfoWindow(content, center) {
  infoWindow.setContent(content);
  infoWindow.setPosition(center);
  infoWindow.open({
    map,
    shouldFocus: false,
  });
}

initMap();

JavaScript

let map;
let featureLayer;
let infoWindow;
let lastInteractedFeatureIds = [];
let lastClickedFeatureIds = [];

function handleClick(/* MouseEvent */ e) {
  lastClickedFeatureIds = e.features.map((f) => f.placeId);
  lastInteractedFeatureIds = [];
  featureLayer.style = applyStyle;
  createInfoWindow(e);
}

function handleMouseMove(/* MouseEvent */ e) {
  lastInteractedFeatureIds = e.features.map((f) => f.placeId);
  featureLayer.style = applyStyle;
}

async function initMap() {
  // Request needed libraries.
  const { Map, InfoWindow } = await google.maps.importLibrary("maps");

  map = new Map(document.getElementById("map"), {
    center: { lat: 39.23, lng: -105.73 },
    zoom: 8,
    // In the cloud console, configure your Map ID with a style that enables the
    // 'Administrative Area Level 2' Data Driven Styling type.
    mapId: "a3efe1c035bad51b",
    mapTypeControl: false,
  });
  // Add the feature layer.
  //@ts-ignore
  featureLayer = map.getFeatureLayer("ADMINISTRATIVE_AREA_LEVEL_2");
  // Add the event listeners for the feature layer.
  featureLayer.addListener("click", handleClick);
  featureLayer.addListener("mousemove", handleMouseMove);
  // Map event listener.
  map.addListener("mousemove", () => {
    // If the map gets a mousemove, that means there are no feature layers
    // with listeners registered under the mouse, so we clear the last
    // interacted feature ids.
    if (lastInteractedFeatureIds?.length) {
      lastInteractedFeatureIds = [];
      featureLayer.style = applyStyle;
    }
  });
  // Create the infowindow.
  infoWindow = new InfoWindow({});
  // Apply style on load, to enable clicking.
  featureLayer.style = applyStyle;
}

// Helper function for the infowindow.
async function createInfoWindow(event) {
  let feature = event.features[0];

  if (!feature.placeId) return;

  // Update the infowindow.
  const place = await feature.fetchPlace();
  let content =
    '<span style="font-size:small">Display name: ' +
    place.displayName +
    "<br/> Place ID: " +
    feature.placeId +
    "<br/> Feature type: " +
    feature.featureType +
    "</span>";

  updateInfoWindow(content, event.latLng);
}

// Define styles.
// Stroke and fill with minimum opacity value.
const styleDefault = {
  strokeColor: "#810FCB",
  strokeOpacity: 1.0,
  strokeWeight: 2.0,
  fillColor: "white",
  fillOpacity: 0.1, // Polygons must be visible to receive events.
};
// Style for the clicked polygon.
const styleClicked = {
  ...styleDefault,
  fillColor: "#810FCB",
  fillOpacity: 0.5,
};
// Style for polygon on mouse move.
const styleMouseMove = {
  ...styleDefault,
  strokeWeight: 4.0,
};

// Apply styles using a feature style function.
function applyStyle(/* FeatureStyleFunctionOptions */ params) {
  const placeId = params.feature.placeId;

  //@ts-ignore
  if (lastClickedFeatureIds.includes(placeId)) {
    return styleClicked;
  }

  //@ts-ignore
  if (lastInteractedFeatureIds.includes(placeId)) {
    return styleMouseMove;
  }
  return styleDefault;
}

// Helper function to create an info window.
function updateInfoWindow(content, center) {
  infoWindow.setContent(content);
  infoWindow.setPosition(center);
  infoWindow.open({
    map,
    shouldFocus: false,
  });
}

initMap();

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;
}

HTML

<html>
  <head>
    <title>Handle Region Boundary Click Event</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>

    <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: "weekly"});</script>
  </body>
</html>

تجربة النموذج

اطّلِع على مزيد من المعلومات عن الأحداث.