javascript - 谷歌地图类型错误: a is null

Question

我必须在我的网络应用程序中使用谷歌地图。问题是我收到一条错误，提示 TypeError: a is null。这是我在窗口加载时调用谷歌地图的方式:

var lat;
var long;
var map;

function geoloc() {//on window load get the user latitude and longitue and pass the values to   "successPosition" function if user allow the geolocation other wise call   "showError" function to gave static latitude and longitude.   


    if (navigator.geolocation) {
        var optn = {
            enableHighAccuracy: true,
            timeout: 0,
            maximumAge: 0
        };

        navigator.geolocation.getCurrentPosition(successPosition, showError, optn);

    } else {
        alert('Geolocation is not supported in your browser');
    }
}

function successPosition(position) {  //get the latitude and longitude by geolocation function


    lat = position.coords.latitude; 
    long = position.coords.longitude;

    initialize(lat, long);//calling the initialize function
}

function initialize(lat, long) {   //initialize the map 

    var myLatlng = new google.maps.LatLng(lat, long);

    var mapOptions = {//maps options the zoom level and map center
        zoom: 4,
        center: myLatlng

    }

    map = new google.maps.Map(document.getElementById('googleMap'), mapOptions);


    var marker = new google.maps.Marker({//create the marker on the map
        position: myLatlng,
        map: map,
        title: 'Hello World!'
    });
}


function showError() {//pass the values to "initialize" function if the user dosn't allow the geolocation 

    initialize(31.5497, 74.3436);
}
google.maps.event.addDomListener(window, 'load', geoloc);//on window load calls the geoloc function to get the user latitude and longitud 

当我在 Firefox 上运行这个程序时，Firebug 告诉我“TypeError: a is null”。我不知道如何修复它。请帮忙!

Answer 1

我尝试了你的代码，它确实创建了一个谷歌地图。我想知道您在运行脚本之前是否正确包含了 Maps API JavaScript。

<script type="text/javascript"
      src="https://maps.googleapis.com/maps/api/js?key=ENTER-YOUR-UNIQUE-KEY-HERE">
</script>

也许该网站的其他部分存在干扰的错误？