拖拽和页面滚动

trackpad 2 mousewheel 2 zoom 8 scroll 2 page 2

本示例演示单指操作滚动页面，双指或者按住（Cmd or Ctrl）操作才控制地图.

本示例演示页面滚动的习惯操作：在触屏设备上，单个手机操作的时候，只滚动页面。当两个手机一起拖拽的时候，才可以操作地图。对于鼠标或者触摸板，只有按住 (Cmd 或者 Ctrl) 键的时候才会拖动缩放地图，否则会滚动页面。

main.js

import Map from 'ol/Map.js';
import OSM from 'ol/source/OSM.js';
import TileLayer from 'ol/layer/Tile.js';
import View from 'ol/View.js';
import {DragPan, MouseWheelZoom, defaults} from 'ol/interaction.js';
import {platformModifierKeyOnly} from 'ol/events/condition.js';

const map = new Map({
  interactions: defaults({dragPan: false, mouseWheelZoom: false}).extend([
    new DragPan({
      condition: function (event) {
        return this.getPointerCount() === 2 || platformModifierKeyOnly(event);
      },
    }),
    new MouseWheelZoom({
      condition: platformModifierKeyOnly,
    }),
  ]),
  layers: [
    new TileLayer({
      source: new OSM(),
    }),
  ],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 2,
  }),
});

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Panning and page scrolling</title>
    <link rel="stylesheet" href="node_modules/ol/ol.css">
    <style>
      .map {
        width: 100%;
        height: 400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="./resources/elm-pep.js"></script>
    <script type="module" src="main.js"></script>
  </body>
</html>

package.json

{
  "name": "two-finger-pan-scroll",
  "dependencies": {
    "ol": "7.3.0"
  },
  "devDependencies": {
    "vite": "^3.2.3"
  },
  "scripts": {
    "start": "vite",
    "build": "vite build"
  }
}