本文说明如何为地图和地图物件加入 Context menu,当您在地图上按滑鼠右键即显示该位置的经纬度。
为了加入 Context menu,首先需要订阅 ContextMenuEvent。 ContextMenuEvent 具有特殊的 items 属性,可以用来存取清单项目。 每个清单项目都是H.util.ContextItem 类别的实例。
JavaScript
function addContextMenus(map) { // 订阅 "contextmenu" 事件 map.addEventListener('contextmenu', function (e) { if (e.target !== map) { return; } var coord = map.screenToGeo(e.viewportX, e.viewportY);// 加入清单项目 item e.items.push(// 建立清单项目 item 显示经纬度 new H.util.ContextItem({ label: [ Math.abs(coord.lat.toFixed(4)) + ((coord.lat > 0) ? 'N' : 'S'), Math.abs(coord.lng.toFixed(4)) + ((coord.lng > 0) ? 'E' : 'W') ].join(' ') }), ); });}/** * map 初始化相关代码: */// Step 1: 初始化 platformvar platform = new H.service.Platform({ apikey: apikey});var defaultLayers = platform.createDefaultLayers();// Step 2: 初始化 mapvar map = new H.Map(document.getElementById('map'), defaultLayers.vector.normal.map, { center: {lat:25.03746, lng:121.564558}, zoom: 9, pixelRatio: window.devicePixelRatio || 1});// Step 3: 建立地图互动性var behavior = new H.mapevents.Behavior(new H.mapevents.MapEvents(map));// Step 4: 建立预设 UI 元件var ui = H.ui.UI.createDefault(map, defaultLayers);addContextMenus(map);
HTML
<!DOCTYPE html><html> <head> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=yes"> <meta http-equiv="Content-type" content="text/html;charset=UTF-8"> <title>Context menu</title> <link rel="stylesheet" type="text/css" href="https://js.api.here.com/v3/3.1/mapsjs-ui.css" /> <link rel="stylesheet" type="text/css" href="demo.css" /> <link rel="stylesheet" type="text/css" href="styles.css" /> <link rel="stylesheet" type="text/css" href="../template.css" /> <script type="text/javascript" src='../test-credentials.js'></script> <script type="text/javascript" src='../js-examples-rendering-helpers/iframe-height.js'></script> <script type="text/javascript" src="https://js.api.here.com/v3/3.1/mapsjs-core.js"></script> <script type="text/javascript" src="https://js.api.here.com/v3/3.1/mapsjs-service.js"></script> <script type="text/javascript" src="https://js.api.here.com/v3/3.1/mapsjs-ui.js"></script> <script type="text/javascript" src="https://js.api.here.com/v3/3.1/mapsjs-mapevents.js"></script> </head> <body id="markers-on-the-map"> <div id="map"></div> <script type="text/javascript" src='demo.js'></script> </body></html>
CSS
#map { width: 95%; height: 450px; background: grey;}#panel { width: 100%; height: 400px;}
执行结果