Question

If the Google Earth app is installed on an iPad (with iOS 4.2 or 5.0.1) a URL scheme link to comgoogleearth:// from an HTML document in Safari or a PDF in GoodReader will open the application.

Is there a way to provide a parameter to specify a location either as a search or as a file in .kml or .kmz? I have tried various syntax without any luck so far.

I already know how to open the location in the Google Maps application – using an http://maps.google.com/ link with appropriate search parameters that is “hijacked” to the Maps app instead of the web site.

I would like to do the same sort of thing with Google Earth if possible.

Answer 1

Not directly no, to date the Apple application protocol for Google Earth doesn’t support any kind of query.

NSString *stringURL = @"comgoogleearth://";
NSURL *url = [NSURL URLWithString:stringURL];
[[UIApplication sharedApplication] openURL:url]

However you could achieve the functionality you require indirectly with a CGI script on a publicly accessible server pretty easily.

1) Create a CGI script that will accept a given latitude and longitude and create a simple KmlPlacemark with the given location.

for example, in PHP:

<?php
// Get the latitude and longitude from the query
if(is_numeric($_GET["lng"]) && is_numeric($_GET["lat"])) {
  $lng = $_GET["lng"];
  $lat = $_GET["lat"];
} else {
  exit();
}

// Creates an array of strings to hold the lines of the KML file.
$kml = array('<?xml version="1.0" encoding="UTF-8"?>');
$kml[] = '<kml xmlns="http://earth.google.com/kml/2.1">';
$kml[] = ' <Document>';
$kml[] = '   <Placemark id="">';
$kml[] = '   <Point>';
$kml[] = '   <coordinates>' . $lng . ','  . $lat . '</coordinates>';
$kml[] = '   </Point>';
$kml[] = '   </Placemark>';
$kml[] = ' </Document>';
$kml[] = '</kml>';
$kmlOutput = join("\n", $kml);
header('Content-type: application/vnd.google-earth.kml+xml');
echo $kmlOutput;
?>

2) Call the Apple application protocol for Google Earth using a url to the CGI script we created that supplies the required coordinates. e.g.

comgoogleearth://www.yourserver.com/kmlScript.php?lng=53.2&lat=34.34

When the URL is loaded the Google Earth app will fly to the location.

This method can be used to generate a location from a search (geocoding) with a slight modification easily.

The only limitation to this is that the IOS device must be able to access the server holding the CGI script (won’t work off-line)