Question

我有一个沿着谷歌地图http://jsfiddle.net/t43kaeyr/移动的标记，但我需要它在地图上移动时绘制路径。

这是创建地图的javascript

var map,marker;

var startPos = [42.42679066670903, -83.29210638999939];
var speed = 150; // km/h

var delay = 100;
// If you set the delay below 1000ms and you go to another tab,
// the setTimeout function will wait to be the active tab again
// before running the code.
// See documentation :
// https://developer.mozilla.org/en-US/docs/Web/API/WindowTimers/setTimeout#Inactive_tabs

function animateMarker(marker, coords, km_h)
{
    var target = 0;
    var km_h = km_h || 50;
    coords.push([startPos[0], startPos[1]]);

    function goToPoint()
    {
        var lat = marker.position.lat();
        var lng = marker.position.lng();
        var step = (km_h * 1000 * delay) / 3600000; // in meters

        var dest = new google.maps.LatLng(
        coords[target][0], coords[target][1]);

        var distance =
        google.maps.geometry.spherical.computeDistanceBetween(
        dest, marker.position); // in meters

        var numStep = distance / step;
        var i = 0;
        var deltaLat = (coords[target][0] - lat) / numStep;
        var deltaLng = (coords[target][1] - lng) / numStep;

        function moveMarker()
        {
            lat += deltaLat;
            lng += deltaLng;
            i += step;

            if (i < distance)
            {
                marker.setPosition(new google.maps.LatLng(lat, lng));
                setTimeout(moveMarker, delay);
            }
            else
            {   marker.setPosition(dest);
                target++;
                if (target == coords.length){ target = 0; }

                setTimeout(goToPoint, delay);
            }
        }
        moveMarker();
    }
    goToPoint();
}

function initialize()
{

    var myOptions = {
        zoom: 16,
        center: new google.maps.LatLng(42.425175091823974, -83.2943058013916),
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);

    marker = new google.maps.Marker({
        position: new google.maps.LatLng(startPos[0], startPos[1]),
        icon: 'assets/images/c.png',
        map: map
    });

    google.maps.event.addListenerOnce(map, 'idle', function()
    {
        animateMarker(marker, [
            // The coordinates of each point you want the marker to go to.
            // You don't need to specify the starting position again.
            [42.42666395645802, -83.29694509506226],
            [42.42300508749226, -83.29679489135742],
            [42.42304468678425, -83.29434871673584],
            [42.424882066428424, -83.2944130897522],
            [42.42495334300206, -83.29203128814697]
        ], speed);
    });

}

initialize();

我尝试绘制路径并正确绘制路径，但对象不再移动。这是代码

var map,marker;

var startPos = [42.42679066670903, -83.29210638999939];
var speed = 150; // km/h

var delay = 100;
// If you set the delay below 1000ms and you go to another tab,
// the setTimeout function will wait to be the active tab again
// before running the code.
// See documentation :
// https://developer.mozilla.org/en-US/docs/Web/API/WindowTimers/setTimeout#Inactive_tabs

function animateMarker(marker, coords, km_h)
{
    var target = 0;
    var km_h = km_h || 50;
    coords.push([startPos[0], startPos[1]]);

    function goToPoint()
    {
        var lat = marker.position.lat();
        var lng = marker.position.lng();
        var step = (km_h * 1000 * delay) / 3600000; // in meters

        var dest = new google.maps.LatLng(
        coords[target][0], coords[target][1]);

        var distance =
        google.maps.geometry.spherical.computeDistanceBetween(
        dest, marker.position); // in meters

        var numStep = distance / step;
        var i = 0;
        var deltaLat = (coords[target][0] - lat) / numStep;
        var deltaLng = (coords[target][1] - lng) / numStep;

        function moveMarker()
        {
            lat += deltaLat;
            lng += deltaLng;
            i += step;

            if (i < distance)
            {
                marker.setPosition(new google.maps.LatLng(lat, lng));
                setTimeout(moveMarker, delay);
            }
            else
            {   marker.setPosition(dest);
                target++;
                if (target == coords.length){ target = 0; }

                setTimeout(goToPoint, delay);
            }
        }
        moveMarker();
    }
    goToPoint();
}

function initialize()
{

    var myOptions = {
        zoom: 16,
        center: new google.maps.LatLng(42.425175091823974, -83.2943058013916),
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);

    marker = new google.maps.Marker({
        position: new google.maps.LatLng(startPos[0], startPos[1]),
        icon: 'assets/images/c.png',
        map: map
    });
    var flightPlanCoordinates = [
    {lat: 42.42666395645802, lng: -83.29694509506226},
    {lat: 42.42300508749226, lng: -83.29679489135742},
    {lat: 42.42304468678425, lng: -83.29434871673584},
    {lat: 42.424882066428424, lng: -83.2944130897522},
    {lat: 42.42495334300206, lng: -83.29203128814697}
  ];

    google.maps.event.addListenerOnce(map, 'idle', function()
    {
        animateMarker(marker, [
            // The coordinates of each point you want the marker to go to.
            // You don't need to specify the starting position again.
            flightPlanCoordinates
        ], speed);
    });
    var flightPath = new google.maps.Polyline({
    path: flightPlanCoordinates,
    geodesic: true,
    strokeColor: '#FF0000',
    strokeOpacity: 1.0,
    strokeWeight: 2
  });

  flightPath.setMap(map);
}

initialize();

如何在地图上移动时让标记绘制路径？

Answer 1

您可能希望使用包含多个点的线创建折线，该线代表标记的每个位置：

提供全局变量：

var map = new google.maps.Map(document.getElementById('map'), {
  zoom: 3,
  center: {lat: 0, lng: -180},
  mapTypeId: google.maps.MapTypeId.TERRAIN
});

var polylineCoords = [];

var path = new google.maps.Polyline({
  path: polylineCoords,
  geodesic: true,
  strokeColor: '#FF0000',
  strokeOpacity: 1.0,
  strokeWeight: 2
});

path.setMap(map);

//To add a Point on the polyline call
function addCoord(lat, lng) {
   var point = new google.maps.LatLng(lat, lng);
   var coords = path.getPath();
   coords.push(point);
}

JSFiddle

绘制路径作为对象在地图上移动

1 个答案: