Geolocation

geocontact.page

<apex:page StandardController="Contact" showHeader="true" sidebar="false">

<script>
var pos = {};
function success(position) {
  pos = position.coords;
  console.log(pos);
}

function error(msg) {
 console.log(msg);
}

if (navigator.geolocation) {
  navigator.geolocation.getCurrentPosition(success, error);
} else {
  error('not supported');
}

function setPos() {
	var inputs = document.getElementsByTagName('input');
	for(var x = 0; x < inputs.length; x++) {
		if(inputs[x].id.indexOf('contactlat') >= 0) { inputs[x].value = pos.latitude; }
		if(inputs[x].id.indexOf('contactlong') >= 0) { inputs[x].value = pos.longitude; }
	}
}

</script>

<apex:form >

<apex:pageBlock>
	<apex:pageBlockButtons>
                <apex:commandButton action="{!quicksave}" value="Save"/>
				<button onClick="setPos(); return false;" id="setPosBtn">Set Position</button>
</apex:pageBlockButtons>
<apex:pageBlockSection title="My Contact" columns="2">
	<apex:inputField value="{!Contact.FirstName}" />
	<apex:inputField value="{!Contact.LastName}" />
	<apex:inputField value="{!Contact.Location__Latitude__s}" id="contactlat" />
	<apex:inputField value="{!Contact.Location__Longitude__s}" id="contactlong" />	
</apex:pageBlockSection>
</apex:pageBlock>	
</apex:form>
	
</apex:page>

geolocation.cls

public with sharing class GeoContactController {

	public GeoContactController() {

	}
	
	public GeoContactController(ApexPages.StandardController stdc) {
		
	}
	
	@RemoteAction
	public static List<Contact> getNearbyContacts(Decimal clat, Decimal clong) {
		String q = 'SELECT Name FROM Contact WHERE DISTANCE(Location__c, GEOLOCATION('+String.valueOf(clat)+','+String.valueOf(clong)+'), "mi") < 10';
		List<Contact> contacts = Database.query(q);
		return contacts;
	}

}

I was getting an error with the class above. I had to change line 13 to the following because I was getting errors with the double quotes:

String q = 'SELECT Name FROM Contact WHERE DISTANCE(Location__c, GEOLOCATION('+String.valueOf(clat)+','+String.valueOf(clong)+'), 'mi') < 10';