var watchID;
var geo; // for the geolocation object
var map; // for the google map object
var mapMarker; // the google map marker object
var markers;
// position options
var MAXIMUM_AGE = 200; // miliseconds
var TIMEOUT = 300000;
var HIGHACCURACY = true;
function getGeoLocation() {
try {
if( !! navigator.geolocation ) return navigator.geolocation;
else return undefined;
} catch(e) {
return undefined;
}
}
function show_map(position) {
var lat = position.coords.latitude;
var lon = position.coords.longitude;
var latlng = new google.maps.LatLng(lat, lon);
ajax_post(lat,lon);
if(map) {
map.panTo(latlng);
mapMarker.setPosition(latlng);
} else {
var myOptions = {
zoom: 18,
center: latlng,
// mapTypeID --
// ROADMAP displays the default road map view
// SATELLITE displays Google Earth satellite images
// HYBRID displays a mixture of normal and satellite views
// TERRAIN displays a physical map based on terrain information.
mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
map.setTilt(0); // turns off the annoying default 45-deg view
mapMarker = new google.maps.Marker({
position: latlng,
title:"You are here."
});
mapMarker.setMap(map);
alert ('in elses statement after map');
}
}
function geo_error(error) {
stopWatching();
switch(error.code) {
case error.TIMEOUT:
alert('Geolocation Timeout');
break;
case error.POSITION_UNAVAILABLE:
alert('Geolocation Position unavailable');
break;
case error.PERMISSION_DENIED:
alert('Geolocation Permission denied');
break;
default:
alert('Geolocation returned an unknown error code: ' + error.code);
}
}
function stopWatching() {
if(watchID) geo.clearWatch(watchID);
watchID = null;
alert ('Hey You Said Stop Watching');
}
function startWatching() {
watchID = geo.watchPosition(show_map, geo_error, {
enableHighAccuracy: HIGHACCURACY,
maximumAge: MAXIMUM_AGE,
timeout: TIMEOUT
});
}
function startmap() {
if((geo = getGeoLocation())) {
startWatching();
} else {
alert('Geolocation not supported.')
}
}
function ajax_post(lat,lon){
// Create our XMLHttpRequest object
var hr = new XMLHttpRequest();
// Create some variables we need to send to our PHP file
var url = "send/mypostion.php";
var vars = "postlat="+lat+"&postlon="+lon;
hr.open("POST", url, true);
// Set content type header information for sending url encoded variables in the request
hr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
// Access the onreadystatechange event for the XMLHttpRequest object
hr.onreadystatechange = function() {
if(hr.readyState == 4 && hr.status == 200) {
// a string looking like: "32.6986, -117.101" (from a comment)
var return_data = hr.responseText;
// alert(return_data);
}
}
// Send the data to PHP now... and wait for response to update the status div
hr.send(vars); // Actually execute the request
}
所以我有这个函数 get_userlat() ，当它被调用时，它应该使用 ajax 从服务器获取用户 lattiude，但是当我调用这个函数时，它调用时不会做任何事情。我正在尝试创建一个跟踪代码，以便您在输入他们的密码和用户电子邮件时能够跟踪您的朋友。我的数据库有用户 lat 和 lng。
function get_userlat(){
// Create our XMLHttpRequest object
var hr = new XMLHttpRequest();
// Create some variables we need to send to our PHP file
var url = "send/getfriendspostion.php";
var vars = "postemail="+prompt("What is your friends email")+"&postpin="+prompt("What is your friends pin number");
hr.open("POST", url, true);
// Set content type header information for sending url encoded variables in the request
hr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
// Access the onreadystatechange event for the XMLHttpRequest object
hr.onreadystatechange = function() {
if(hr.readyState == 4 && hr.status == 200) {
var return_data = hr.responseText;
//addMarker(return_data);
addMarker(return_data);
return return_data;
}
}
// Send the data to PHP now... and wait for response to update the status div
hr.send(vars); // Actually execute the request
}
function addMarker(location) {
var markers=new google.maps.Marker({
position:location,
});
markers.setMap(map);
}