绘图管理器未显示在Google地图上

Question

您能否看一下这段代码，让我知道为什么绘图管理器没有显示在地图上？

$(document).ready(function () {
    var map;
    var latlng = new google.maps.LatLng(49.241943, -122.889318);
    var myOptions = {
        zoom: 12,
        center: latlng,
        disableDefaultUI: true,
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };

    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);

    var drawingManager = new google.maps.drawing.DrawingManager({
        drawingMode: google.maps.drawing.OverlayType.MARKER,
        drawingControl: true,
        drawingControlOptions: {
            position: google.maps.ControlPosition.TOP_CENTER,
            drawingModes: [
                google.maps.drawing.OverlayType.MARKER,
                google.maps.drawing.OverlayType.CIRCLE,
                google.maps.drawing.OverlayType.POLYGON,
                google.maps.drawing.OverlayType.POLYLINE,
                google.maps.drawing.OverlayType.RECTANGLE
            ]
        },
        markerOptions: {
            icon: 'images/beachflag.png'
        },
        circleOptions: {
            fillColor: '#ffff00',
            fillOpacity: 1,
            strokeWeight: 5,
            clickable: false,
            editable: true,
            zIndex: 1
        }
    });
    drawingManager.setMap(map);

});

我检查了控制台，并收到以下错误消息：

未捕获的TypeError：无法读取未定义的属性'DrawingManager'

您能告诉我为什么会这样吗？

Answer 1

好的，我知道了

我不得不将Google Map Javascript库更改为

<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false&libraries=drawing"></script>