javascript - Google Maps API - 多个 map 的多个标记

Question

我正在创建一个新页面，其中基本上有 2 个带有自己标记的 map 。

我已经使用此处提供的代码设法让第一张 map 正常工作 http://wrightshq.com/playground/placing-multiple-markers-on-a-google-map-using-api-3/效果很好...但是当我尝试复制代码并更改 map Canvas 时，第二张 map 没有加载。

这是我目前的代码:

jQuery(function($) {
    // Asynchronously Load the map API 
    var script = document.createElement('script');
    script.src = "http://maps.googleapis.com/maps/api/js?sensor=false&callback=initialize";
    document.body.appendChild(script);

    // Asynchronously Load the map API 
    var script2 = document.createElement('script');
    script2.src = "http://maps.googleapis.com/maps/api/js?sensor=false&callback=initialize2";
    document.body.appendChild(script2);
});

function initialize() {
    var map;
    var bounds = new google.maps.LatLngBounds();
    var mapOptions = {
        mapTypeId: 'roadmap'
    };

    // Display a map on the page
    map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
    map.setTilt(45);

    // Multiple Markers
    var markers = [
        ['London Eye, London', 51.503454,-0.119562],
        ['Palace of Westminster, London', 51.499633,-0.124755]
    ];

    // Info Window Content
    var infoWindowContent = [
        ['<div class="info_content">' +
        '<h3>London Eye</h3>' +
        '<p>The London Eye is a giant Ferris wheel situated on the banks of the River Thames. The entire structure is 135 metres (443 ft) tall and the wheel has a diameter of 120 metres (394 ft).</p>' +        '</div>'],
        ['<div class="info_content">' +
        '<h3>Palace of Westminster</h3>' +
        '<p>The Palace of Westminster is the meeting place of the House of Commons and the House of Lords, the two houses of the Parliament of the United Kingdom. Commonly known as the Houses of Parliament after its tenants.</p>' +
        '</div>']
    ];

    // Display multiple markers on a map
    var infoWindow = new google.maps.InfoWindow(), marker, i;

    // Loop through our array of markers & place each one on the map  
    for( i = 0; i < markers.length; i++ ) {
        var position = new google.maps.LatLng(markers[i][1], markers[i][2]);
        bounds.extend(position);
        marker = new google.maps.Marker({
            position: position,
            map: map,
            title: markers[i][0]
        });

        // Allow each marker to have an info window    
        google.maps.event.addListener(marker, 'click', (function(marker, i) {
            return function() {
                infoWindow.setContent(infoWindowContent[i][0]);
                infoWindow.open(map, marker);
            }
        })(marker, i));

        // Automatically center the map fitting all markers on the screen
        map.fitBounds(bounds);
    }

    // Override our map zoom level once our fitBounds function runs (Make sure it only runs once)
    var boundsListener = google.maps.event.addListener((map), 'bounds_changed', function(event) {
        this.setZoom(14);
        google.maps.event.removeListener(boundsListener);
    });

}

function initialize2() {
    var map;
    var bounds = new google.maps.LatLngBounds();
    var mapOptions = {
        mapTypeId: 'roadmap'
    };

    // Display a map on the page
    map = new google.maps.Map(document.getElementById("map_canvas2"), mapOptions);
    map.setTilt(45);

    // Multiple Markers
    var markers = [
        ['London Eye, London', 51.503454,-0.119562],
        ['Palace of Westminster, London', 51.499633,-0.124755]
    ];

    // Info Window Content
    var infoWindowContent = [
        ['<div class="info_content">' +
        '<h3>London Eye</h3>' +
        '<p>The London Eye is a giant Ferris wheel situated on the banks of the River Thames. The entire structure is 135 metres (443 ft) tall and the wheel has a diameter of 120 metres (394 ft).</p>' +        '</div>'],
        ['<div class="info_content">' +
        '<h3>Palace of Westminster</h3>' +
        '<p>The Palace of Westminster is the meeting place of the House of Commons and the House of Lords, the two houses of the Parliament of the United Kingdom. Commonly known as the Houses of Parliament after its tenants.</p>' +
        '</div>']
    ];

    // Display multiple markers on a map
    var infoWindow = new google.maps.InfoWindow(), marker, i;

    // Loop through our array of markers & place each one on the map  
    for( i = 0; i < markers.length; i++ ) {
        var position = new google.maps.LatLng(markers[i][1], markers[i][2]);
        bounds.extend(position);
        marker = new google.maps.Marker({
            position: position,
            map: map,
            title: markers[i][0]
        });

        // Allow each marker to have an info window    
        google.maps.event.addListener(marker, 'click', (function(marker, i) {
            return function() {
                infoWindow.setContent(infoWindowContent[i][0]);
                infoWindow.open(map, marker);
            }
        })(marker, i));

        // Automatically center the map fitting all markers on the screen
        map.fitBounds(bounds);
    }

    // Override our map zoom level once our fitBounds function runs (Make sure it only runs once)
    var boundsListener = google.maps.event.addListener((map), 'bounds_changed', function(event) {
        this.setZoom(14);
        google.maps.event.removeListener(boundsListener);
    });

}
</script>

有没有人设法做到这一点？

Answer 1

问题是您要加载 Maps API JS 文件两次，使用

var script = document.createElement('script');
script.src = "http://maps.googleapis.com/maps/api/js?sensor=false&callback=initialize";
document.body.appendChild(script);

// Asynchronously Load the map API 
var script2 = document.createElement('script');
script2.src = "http://maps.googleapis.com/maps/api/js?sensor=false&callback=initialize2";
document.body.appendChild(script2);

您不需要这样做，只需加载一次。

然后您的两个函数 initialize 和 initialize2 几乎相同，除了您的 map Canvas 的名称。这违背了使用函数的意义。摆脱 initialize2。

将您当前在初始化中获得的内容移动到它自己的函数中；我们称它为 createMap。创建一个新的初始化函数，通过 map 回调参数调用，调用此 createMap 函数两次，使用您需要的任何参数来设置它们之间的差异。

像这样:

jQuery(function($) {
    // Asynchronously Load the map API 
    var script = document.createElement('script');
    script.src = "http://maps.googleapis.com/maps/api/js?callback=initialize";
    document.body.appendChild(script);
});

function initialize() {
    createMap('map_canvas');
    createMap('map_canvas2');
}

function createMap(mapCanvas) {
    var map;
    var bounds = new google.maps.LatLngBounds();
    var mapOptions = {
        mapTypeId: 'roadmap'
    };

    // Display a map on the page
    map = new google.maps.Map(document.getElementById(mapCanvas), mapOptions);
    map.setTilt(45);

    // Multiple Markers
    var markers = [
        ['London Eye, London', 51.503454,-0.119562],
        ['Palace of Westminster, London', 51.499633,-0.124755]
    ];

    // Info Window Content
    var infoWindowContent = [
        ['<div class="info_content">' +
        '<h3>London Eye</h3>' +
        '<p>The London Eye is a giant Ferris wheel situated on the banks of the River Thames. The entire structure is 135 metres (443 ft) tall and the wheel has a diameter of 120 metres (394 ft).</p>' +        '</div>'],
        ['<div class="info_content">' +
        '<h3>Palace of Westminster</h3>' +
        '<p>The Palace of Westminster is the meeting place of the House of Commons and the House of Lords, the two houses of the Parliament of the United Kingdom. Commonly known as the Houses of Parliament after its tenants.</p>' +
        '</div>']
    ];

    // Display multiple markers on a map
    var infoWindow = new google.maps.InfoWindow(), marker, i;

    // Loop through our array of markers & place each one on the map  
    for( i = 0; i < markers.length; i++ ) {
        var position = new google.maps.LatLng(markers[i][1], markers[i][2]);
        bounds.extend(position);
        marker = new google.maps.Marker({
            position: position,
            map: map,
            title: markers[i][0]
        });

        // Allow each marker to have an info window    
        marker.addListener('click', (function(marker, i) {
            return function() {
                infoWindow.setContent(infoWindowContent[i][0]);
                infoWindow.open(map, marker);
            }
        })(marker, i));

        // Automatically center the map fitting all markers on the screen
        map.fitBounds(bounds);
    }

    // Override our map zoom level once our fitBounds function runs (Make sure it only runs once)
    var boundsListener = map.addListener(('bounds_changed', function() {
        this.setZoom(14);
        google.maps.event.removeListener(boundsListener);
    });
}

假设每个 map 都有不同的标记，您可能想在初始化函数中设置标记，并将其作为附加参数传递给 createMap 函数。