mapbox-gl 鼠标事件解读

最新推荐文章于 2025-03-31 22:38:22 发布

aganliang

最新推荐文章于 2025-03-31 22:38:22 发布

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分类专栏： mapbox Node.js 文章标签： js javascript canvas html css

本文链接：https://blog.youkuaiyun.com/aganliang/article/details/117856786

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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Create a draggable point</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v2.3.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v2.3.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<style>
    .coordinates {
        background: rgba(0, 0, 0, 0.5);
        color: #fff;
        position: absolute;
        bottom: 40px;
        left: 10px;
        padding: 5px 10px;
        margin: 0;
        font-size: 11px;
        line-height: 18px;
        border-radius: 3px;
        display: none;
    }
</style>

<div id="map"></div>
<pre id="coordinates" class="coordinates"></pre>

<script>
	mapboxgl.accessToken = 'pk.eyJ1IjoiYWdhbmxpYW5nIiwiYSI6ImNrYndkZ2dqdzBldzQycmxna3RrZ3ZrMDIifQ.mMruQKqeJPDcqpV7HEFSLA';
    var coordinates = document.getElementById('coordinates');
    var map = new mapboxgl.Map({
        container: 'map',
        style: 'mapbox://styles/mapbox/streets-v11',
        center: [0, 0],
        zoom: 2
    });

    var canvas = map.getCanvasContainer();
	console.log(canvas);

    // 定义 source
    var geojson = {
        'type': 'FeatureCollection',
        'features': [
            {
                'type': 'Feature',
                'geometry': {
                    'type': 'Point',
                    'coordinates': [0, 0]
                }
            }
        ]
    };

    // 按住鼠标移动的回调函数
    function onMove(e) {
        var coords = e.lngLat;

        // Set a UI indicator for dragging.
        canvas.style.cursor = 'grabbing';

        // Update the Point feature in `geojson` coordinates
        // and call setData to the source layer `point` on it.
        geojson.features[0].geometry.coordinates = [coords.lng, coords.lat];
        map.getSource('point').setData(geojson);
    }

    // 按住鼠标移动之后，放开的回调函数
    function onUp(e) {
        var coords = e.lngLat;

        // Print the coordinates of where the point had
        // finished being dragged to on the map.
        coordinates.style.display = 'block';
        coordinates.innerHTML =
            'Longitude: ' + coords.lng + '<br />Latitude: ' + coords.lat;
        canvas.style.cursor = '';

        // Unbind mouse/touch events
        map.off('mousemove', onMove);
        map.off('touchmove', onMove);
    }

    // 底图加载之后，addSource, addLayer,
    // 一直监听 mouseenter ,mouseleave, mousedown 事件
    // 监听一次 mouseup 事件
    // 不同事件，canvas.style.cursor 不同设置
    map.on('load', function () {
        // Add a single point to the map.
        map.addSource('point', {
            'type': 'geojson',
            'data': geojson
        });

        map.addLayer({
            'id': 'point',
            'type': 'circle',
            'source': 'point',
            'paint': {
                'circle-radius': 10,
                'circle-color': '#F84C4C' // red color
            }
        });

        // When the cursor enters a feature in
        // the point layer, prepare for dragging.
        map.on('mouseenter', 'point', function () {
            map.setPaintProperty('point', 'circle-color', '#3bb2d0');
            canvas.style.cursor = 'move';
        });

        map.on('mouseleave', 'point', function () {
            map.setPaintProperty('point', 'circle-color', '#3887be');
            canvas.style.cursor = '';
        });

        map.on('mousedown', 'point', function (e) {
            // Prevent the default map drag behavior.
            e.preventDefault();

            canvas.style.cursor = 'grab';

            map.on('mousemove', onMove);
            map.once('mouseup', onUp);
        });

        map.on('touchstart', 'point', function (e) {
            if (e.points.length !== 1) return;

            // Prevent the default map drag behavior.
            e.preventDefault();

            map.on('touchmove', onMove);
            map.once('touchend', onUp);
        });
    });
</script>

</body>
</html>