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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, mapTypeId: google.maps.MapTypeId.ROADMAP, 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_point, 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> <link href="/maps/documentation/javascript/examples/default.css" rel="stylesheet"> <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, mapTypeId: google.maps.MapTypeId.ROADMAP, 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_point, 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>