Tuesday, December 18, 2012

Tired eyes? Code on the dark side.

If you have a Mac, press ctrl-alt-command+8 and the screen colours invert.  Great for the eyes.  I wonder how many other obscure useful key combinations are hiding in OSX for me to discover?

I've been trying out IntelliJ IDEA again today and love the new "Darcular" theme that makes is easy on the eyes, especially at night. I do think that, given time, I would come to prefer it over Eclipse.  It seems everybody does.  The basic premise that a comercial product will have less bugs and more features holds true because they have more incentive to keep customers happy.

This week however, I do not have the time to re-learn all the keybindings and figure out where the configuration options are.  Once again I've put it aside till another day... or decade.


Wednesday, December 12, 2012

Google Maps v3 with GWT - Example

For a long time there was no official port of Google Maps v3 to GWT.  This issue, created in June 2010, is still marked as "Started".  Comments on that issue seem to indicate that the problem was due to the difficulty in generating the bindings automatically so it would be easy to keep in sync with the JavaScript API.  The older v2 maps API also did not use overlay types which allows more optimised code to be generated, which v3 does.

Finally in March 2012 an official "prerelease" build was posted to the issue but never properly released.  However, it is very usable and seems quite complete.  One nice thing is that because it is generated automatically from the JavaScript API, it matches up very closely to the official docs.  An obvious exception to this is the central class is name GoogleMap rather than Map for obvious reasons.

I'll write a little about getting started using these maps and include a little demo.  The demo uses your current location (from HTML5 geo location object) and draws a circle on the map where it things you are.  The map is zoomed according to how accurate the reading is so the circle should look about the same size no matter what the accuracy.

Start by getting the jar and putting it in a folder somewhere (not in your WEB-INF) and add it to your class path.  Keep an eye on the downloads page in case a more recent lib is released.  At this point it is for the Maps 3.8.1 API which is a already a little out of date but looking at the changelog, I can't see any great features I'd be missing.

First here is the working demo: (watch out for the dialog asking if it can use your location)


and here is the code... First the module
<module rename-to="mapdemo">
  <inherits name="com.google.gwt.user.User"/>
  <inherits name="com.google.maps.gwt.GoogleMaps"/>
  <entry-point class="com.vercer.mapdemo.client.Mapdemo"/>
  <add-linker name="xsiframe" />
</module>
and the GWT code to create a JS file that can be used "cross site"

public class Mapdemo implements EntryPoint
{
 public void onModuleLoad()
 {
  Geolocation geolocation = Geolocation.getIfSupported();
  if (geolocation == null)
  {
   Window.alert("Your old browser is stuck in the past");
  }
  
  geolocation.getCurrentPosition(new Callback<Position, PositionError>()
  {
   
   @Override
   public void onSuccess(Position result)
   {
    display(result.getCoordinates());
   }
   
   @Override
   public void onFailure(PositionError reason)
   {
    Window.alert(reason.getMessage());
   }
  });
 }

 protected void display(Coordinates coordinates)
 {
  // create a bounds 10 times larger than the accuracy error
  LatLng center = LatLng.create(coordinates.getLatitude(), coordinates.getLongitude());
  LatLng sw = Spherical.computeOffset(center, coordinates.getAccuracy() * 10, 225);
  LatLng ne = Spherical.computeOffset(center, coordinates.getAccuracy() * 10, 45);
  
  LatLngBounds outer = LatLngBounds.create(sw, ne);
  
  // create the map
  MapOptions mapOptions = MapOptions.create();
  mapOptions.setMapTypeId(MapTypeId.HYBRID);
  GoogleMap map = GoogleMap.create(Document.get().getElementById("map"), mapOptions);
  map.fitBounds(outer);
  
  // create a circle the size of the error
  CircleOptions circleOptions = CircleOptions.create();
  circleOptions.setFillOpacity(0.2);
  circleOptions.setFillColor("yellow");
  circleOptions.setStrokeColor("yellow");
  Circle circle = Circle.create(circleOptions);
  circle.setCenter(center);
  circle.setRadius(coordinates.getAccuracy());
  circle.setMap(map);
 }
}

Wednesday, November 28, 2012

Moving domains from 1 and 1 to NameCheap

Every time I think of a new "killer start-up" website idea I rush to domainsbot.com to find that perfect .com domain name that maybe - just maybe - is still unregistered.  Normally I'm disappointed to find that almost every combination of relavent keywords was registered by domain squatters years ago.  I end up with some mediocre name with far too many letters and maybe the odd hyphen or two.  But I register them anyway.

Previously I used 1and1.com because ... well they were cheap - like 8.99 (now 10.99).  But unfortunately there are other costs: my time, my sanity and full rights to use my domain how I need.

Firstly, the user interface for their admin console seems to have been carefully designed to enrage its users.  Trying to do any simple task involves checking boxes and selecting obscure menu items and then waiting... maybe it will happen, maybe it won't.  Cancelling anything is virtually impossible.  Transferring your domain to another host is less fun than putting a hot poker up your pee hole.

But the biggest aggravation is that their DNS system does not let you define a wild card subdomain like *.vercer.com.  When I build a website I like to have several versions live for clients to check out such as test.example.com and demo.example.com.  Also, a cool new feature of Google App Engine (GAE) is that it will map application versions to subdomains automatically.  So if I put a new version live "2012-11-28" I can see it at 2012-11-28.example.com without any extra configuration.

But not with 1and1.com.  Oh no.  In fact they limit you to making 5 subs domains on all of your domains.  If you have 20 domains with them you can still only create 5 subdomains between all of them.  Pathetic really.  They do this to force you to buy a more expensive package that allows you to use your own damn domain name how you bloody well like.  Infuriating.  If only they had a warning on their home page: "We are cheap but we will shaft you eventually"

So I googled about a bit for a good, cheap, popular domain host and came to NameCheap.  I'm pretty happy with that choice so far.  The UI is a bit dated but does everything I need without the hair-pulling-out.

The price is right too - I paid 8.69 USD for each transfer for a year including privacy protection.  That was using some discount code I pinched off the web SWITCH2NC that gives 1 dollar off.

Now I am happily all transferred over to NameCheap and it was a breeze.  Wild card subdomains are F.A.B.

So its cheaper and better.  The end.