我创建了一个HTML页面，用于搜索2个邮政编码，并在它们之间创建路由。
我用过： Google Map + Direction-用于在地图上显示路线，就像GPS GeoCoding-用于从邮政编码获取位置
问题：当我单击“开始！”时第一次单击该按钮，我的变量未定义，第二次正常。
我的代码可能出什么问题了？
感谢高级， 史蒂夫
代码：
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Displaying Text Directions With setPanel()</title>
<style>
/* Always set the map height explicitly to define the size of the div
* element that contains the map. */
#map {
height: 100%;
}
/* Optional: Makes the sample page fill the window. */
html, body {
height: 100%;
margin: 0;
padding: 0;
}
#floating-panel {
position: absolute;
top: 10px;
left: 25%;
z-index: 5;
background-color: #fff;
padding: 5px;
border: 1px solid #999;
text-align: center;
font-family: 'Roboto','sans-serif';
line-height: 30px;
padding-left: 10px;
}
#right-panel {
font-family: 'Roboto','sans-serif';
line-height: 30px;
padding-left: 10px;
}
#right-panel select, #right-panel input {
font-size: 15px;
}
#right-panel select {
width: 100%;
}
#right-panel i {
font-size: 12px;
}
#right-panel {
height: 100%;
float: right;
width: 390px;
overflow: auto;
}
#map {
margin-right: 400px;
}
#floating-panel {
background: #fff;
padding: 5px;
font-size: 14px;
font-family: Arial;
border: 1px solid #ccc;
box-shadow: 0 2px 2px rgba(33, 33, 33, 0.4);
display: none;
}
@media print {
#map {
height: 500px;
margin: 0;
}
#right-panel {
float: none;
width: auto;
}
}
</style>
<!--async defer-->
<script
src="https://maps.googleapis.com/maps/api/js?key=MY_API_KEY">
</script>
</head>
<body onload="initMap()">
<div id="floating-panel">
<form onsubmit="codeAddress(); return false" action="#">
<strong>Start:</strong>
<input id="start" size="30" type="text" value="403503" />
<br>
<strong>End:</strong>
<input id="end" size="30" type="text" value="788003" />
<input type="submit" value="GO!">
<input type="button" onclick="clear()" value="Clear markers" />
</form>
</div>
<div id="right-panel"></div>
<div id="map"></div>
<script>
var map;
var directionsDisplay;
var directionsService;
var firstAddress;
var secondAddress;
var geocoder;
function initMap() {
directionsDisplay = new google.maps.DirectionsRenderer;
directionsService = new google.maps.DirectionsService;
map = new google.maps.Map(document.getElementById('map'), {
zoom: 7,
center: {lat: 41.85, lng: -87.65}
});
directionsDisplay.setMap(map);
directionsDisplay.setPanel(document.getElementById('right-panel'));
var control = document.getElementById('floating-panel');
control.style.display = 'block';
map.controls[google.maps.ControlPosition.TOP_CENTER].push(control);
/*geocoder = new google.maps.Geocoder();*/
/*var onChangeHandler = function() {
calculateAndDisplayRoute(directionsService, directionsDisplay);
};
document.getElementById('searchBtn').addEventListener('click', onChangeHandler);*/
// document.getElementById('end').addEventListener('change', onChangeHandler);
}
function clear()
{
map.clearOverlays();
firstAddress="";
secondAddress="";
}
function calculateAndDisplayRoute(directionsService, directionsDisplay) {
var start = firstAddress;
var end = secondAddress;
alert('Start:' + firstAddress + ' End: '+secondAddress);
directionsService.route({
origin: start,
destination: end,
travelMode: 'DRIVING'
}, function(response, status) {
if (status === 'OK') {
directionsDisplay.setDirections(response);
} else {
window.alert('Directions request failed due to ' + status);
}
});
}
function codeAddress() {
var zip1 = document.getElementById('start').value;
var zip2 = document.getElementById('end').value;
/*firstAddress="";
secondAddress="";*/
geocoder = new google.maps.Geocoder();
geocoder.geocode( { 'address': zip1}, function(results1, status1) {
if (status1 == google.maps.GeocoderStatus.OK) {
/*map.setCenter(results[0].geometry.location);
if(marker)
marker.setMap(null);
marker = new google.maps.Marker({
map: map,
position: results[0].geometry.location,
draggable: true
});
google.maps.event.addListener(marker, "dragend", function() {
document.getElementById('lat').value = marker.getPosition().lat();
document.getElementById('lng').value = marker.getPosition().lng();
});
document.getElementById('lat').value = marker.getPosition().lat();
document.getElementById('lng').value = marker.getPosition().lng();*/
firstAddress=results1[0].geometry.location;
alert();
} else {
alert('Geocode Zipcode 1 was not successful for the following reason: ' + status);
}
});
geocoder.geocode( { 'address': zip2}, function(results2, status2) {
if (status2 == google.maps.GeocoderStatus.OK) {
/*map.setCenter(results[0].geometry.location);
if(marker)
marker.setMap(null);
marker = new google.maps.Marker({
map: map,
position: results[0].geometry.location,
draggable: true
});
google.maps.event.addListener(marker, "dragend", function() {
document.getElementById('lat').value = marker.getPosition().lat();
document.getElementById('lng').value = marker.getPosition().lng();
});
document.getElementById('lat').value = marker.getPosition().lat();
document.getElementById('lng').value = marker.getPosition().lng();*/
secondAddress=results2[0].geometry.location;
} else {
alert('Geocode Zipcode 2 was not successful for the following reason: ' + status);
}
});
/*directionsDisplay.setMap(map);
directionsDisplay.setPanel(document.getElementById('right-panel'));
var control = document.getElementById('floating-panel');
control.style.display = 'block';
map.controls[google.maps.ControlPosition.TOP_CENTER].push(control);*/
calculateAndDisplayRoute(directionsService, directionsDisplay);
}
</script>
<!--async defer-->
<!--<script
src="https://maps.googleapis.com/maps/api/js?key=MY_API_KEY&callback=initMap">
</script>-->
</body>
</html>
答案 0 :(得分：2)
function codeAddress() {
var zip1 = document.getElementById('start').value;
var zip2 = document.getElementById('end').value;
geocoder = new google.maps.Geocoder();
var promise1 = new Promise(function(res, rej){
geocoder.geocode( { 'address': zip1}, function(results1, status1) {
if (status1 == google.maps.GeocoderStatus.OK) {
resolve(results1[0].geometry.location);
} else {
reject('Geocode Zipcode 1 was not successful for the following reason: ' + status);
}
});
});
var promise2 = new Promise(function(res, rej){
geocoder.geocode( { 'address': zip2}, function(results2, status2) {
if (status2 == google.maps.GeocoderStatus.OK) {
secondAddress=results2[0].geometry.location;
} else {
alert('Geocode Zipcode 2 was not successful for the following reason: ' + status);
}
});
});
Promise.all([promise1, promise2]).then(values = {
firstAddress = values[0];
secondAddress = values[1];
calculateAndDisplayRoute(directionsService, directionsDisplay);
})
}
只是希望Google API始终能够响应您的代码调用。两次调用都可以响应后，它将调用您的最后一个函数