View this example full screen.
var map;
var directionsDisplay;
var directionsService;
var stepDisplay;
var markerArray = [];
function initialize() {
// Instantiate a directions service.
directionsService = new google.maps.DirectionsService();
// Create a map and center it on Manhattan.
var manhattan = new google.maps.LatLng(40.7711329, -73.9741874);
var mapOptions = {
zoom: 13,
center: manhattan
}
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
// Create a renderer for directions and bind it to the map.
var rendererOptions = {
map: map
}
directionsDisplay = new google.maps.DirectionsRenderer(rendererOptions)
// Instantiate an info window to hold step text.
stepDisplay = new google.maps.InfoWindow();
}
function calcRoute() {
// First, remove any existing markers from the map.
for (var i = 0; i < markerArray.length; i++) {
markerArray[i].setMap(null);
}
// Now, clear the array itself.
markerArray = [];
// Retrieve the start and end locations and create
// a DirectionsRequest using WALKING directions.
var start = document.getElementById('start').value;
var end = document.getElementById('end').value;
var request = {
origin: start,
destination: end,
travelMode: google.maps.TravelMode.WALKING
};
// Route the directions and pass the response to a
// function to create markers for each step.
directionsService.route(request, function(response, status) {
if (status == google.maps.DirectionsStatus.OK) {
var warnings = document.getElementById('warnings_panel');
warnings.innerHTML = '<b>' + response.routes[0].warnings + '</b>';
directionsDisplay.setDirections(response);
showSteps(response);
}
});
}
function showSteps(directionResult) {
// For each step, place a marker, and add the text to the marker's
// info window. Also attach the marker to an array so we
// can keep track of it and remove it when calculating new
// routes.
var myRoute = directionResult.routes[0].legs[0];
for (var i = 0; i < myRoute.steps.length; i++) {
var marker = new google.maps.Marker({
position: myRoute.steps[i].start_location,
map: map
});
attachInstructionText(marker, myRoute.steps[i].instructions);
markerArray[i] = marker;
}
}
function attachInstructionText(marker, text) {
google.maps.event.addListener(marker, 'click', function() {
// Open an info window when the marker is clicked on,
// containing the text of the step.
stepDisplay.setContent(text);
stepDisplay.open(map, marker);
});
}
google.maps.event.addDomListener(window, 'load', initialize);
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Directions service (complex)</title>
<style>
html, body, #map-canvas {
height: 100%;
margin: 0px;
padding: 0px
}
#panel {
position: absolute;
top: 5px;
left: 50%;
margin-left: -180px;
z-index: 5;
background-color: #fff;
padding: 5px;
border: 1px solid #999;
}
</style>
<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>
<script>
var map;
var directionsDisplay;
var directionsService;
var stepDisplay;
var markerArray = [];
function initialize() {
// Instantiate a directions service.
directionsService = new google.maps.DirectionsService();
// Create a map and center it on Manhattan.
var manhattan = new google.maps.LatLng(40.7711329, -73.9741874);
var mapOptions = {
zoom: 13,
center: manhattan
}
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
// Create a renderer for directions and bind it to the map.
var rendererOptions = {
map: map
}
directionsDisplay = new google.maps.DirectionsRenderer(rendererOptions)
// Instantiate an info window to hold step text.
stepDisplay = new google.maps.InfoWindow();
}
function calcRoute() {
// First, remove any existing markers from the map.
for (var i = 0; i < markerArray.length; i++) {
markerArray[i].setMap(null);
}
// Now, clear the array itself.
markerArray = [];
// Retrieve the start and end locations and create
// a DirectionsRequest using WALKING directions.
var start = document.getElementById('start').value;
var end = document.getElementById('end').value;
var request = {
origin: start,
destination: end,
travelMode: google.maps.TravelMode.WALKING
};
// Route the directions and pass the response to a
// function to create markers for each step.
directionsService.route(request, function(response, status) {
if (status == google.maps.DirectionsStatus.OK) {
var warnings = document.getElementById('warnings_panel');
warnings.innerHTML = '<b>' + response.routes[0].warnings + '</b>';
directionsDisplay.setDirections(response);
showSteps(response);
}
});
}
function showSteps(directionResult) {
// For each step, place a marker, and add the text to the marker's
// info window. Also attach the marker to an array so we
// can keep track of it and remove it when calculating new
// routes.
var myRoute = directionResult.routes[0].legs[0];
for (var i = 0; i < myRoute.steps.length; i++) {
var marker = new google.maps.Marker({
position: myRoute.steps[i].start_location,
map: map
});
attachInstructionText(marker, myRoute.steps[i].instructions);
markerArray[i] = marker;
}
}
function attachInstructionText(marker, text) {
google.maps.event.addListener(marker, 'click', function() {
// Open an info window when the marker is clicked on,
// containing the text of the step.
stepDisplay.setContent(text);
stepDisplay.open(map, marker);
});
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>
</head>
<body>
<div id="panel">
<b>Start: </b>
<select id="start">
<option value="penn station, new york, ny">Penn Station</option>
<option value="grand central station, new york, ny">Grand Central Station</option>
<option value="625 8th Avenue, New York, NY, 10018">Port Authority Bus Terminal</option>
<option value="staten island ferry terminal, new york, ny">Staten Island Ferry Terminal</option>
<option value="101 E 125th Street, New York, NY">Harlem - 125th St Station</option>
</select>
<b>End: </b>
<select id="end" onchange="calcRoute();">
<option value="260 Broadway New York NY 10007">City Hall</option>
<option value="W 49th St & 5th Ave, New York, NY 10020">Rockefeller Center</option>
<option value="moma, New York, NY">MOMA</option>
<option value="350 5th Ave, New York, NY, 10118">Empire State Building</option>
<option value="253 West 125th Street, New York, NY">Apollo Theater</option>
<option value="1 Wall St, New York, NY">Wall St</option>
</select>
</div>
<div id="map-canvas"></div>
<div id="warnings_panel" style="width:100%;height:10%;text-align:center"></div>
</body>
</html>