The Redline Challenge

For one reason or another we decided to sponsor a pub crawl this weekend. The plan was hatched over some beers at Underbones on Thursday night for a Saturday morning go time. We knew we basically needed three things: a list of bars, some swag (tshirt?), and obviously a website. We decided that the route of the crawl should follow the MBTA Redline so that we could start downtown and then finish in Somerville. This made picking bars pretty simple, gave us some branding, and of course we registered
REDLINECHALLENGE.COM.

We wanted the website to have some informative information, live location updates, and of course pictures of the debauchery. The biggest problem was that neither Daum nor I have location aware phones. To get around this, we decided to update Twitter with our current location along with a “#loc” hashtag and then have the site update based on that. Since we were all ready using Twitter, we decided to use Twitpic to allow us to post pictures to twitter on the fly. Additionally, we took advantage of Verizon Wireless’s email to SMS service and allowed people to contact us via the website. All told, we built the site in about 3 hours and it proved to be pretty useful. People used it to find us on the crawl and to contact us while we were out. Everyone also got a kick of seeing a live photo stream.

What’s next? Clearly, The Greenline Challenge.

Google Calendar API create on alternate calendar

A few months ago we integrated Google calendar into an application that we built for a client. Anyway, today I sat down to customize which calendars certain events were being created on. We’re using the Zend Framework’s GData package to interact with Google Calendar and surprisingly the documentation is pretty lacking.

Specifically, I was looking to create events on a calendar that was not the “primary” calendar for a user. After poking around and experimenting, I finally got things to work.

First, you can retrieve the list of available calendars with:

Next, when creating the events pass in the uri and the events will appear on the alternate calendar.

self::$service->insertEvent($event, $arr[1][“uri”]);

Client side RSS aggregator

One of our clients came to us a few days ago asking us if we could build something to aggregate several RSS feeds and then display it on their site.

Easy enough. Except the caveats were 1) This had to be done on a shoe string budget and 2) We had no permission to script on the server side (only client side scripting allowed kids).

We put our heads together and realized that Yahoo Pipes would provide the functionality to easily combine several RSS feeds, sort them, filter them, ect. And best part? It’s all built and all free. Pipes also provides the functionality to export a pipe as a JSON feed (as opposed to RSS).

So that takes care of problem 1 and almost fixes problem 2. Of course the remaining problem is getting around the cross domain XHR restrictions on the JSON. I did some poking around the Yahoo Pipes documentation and it turns out you can add a _callback parameter to the URL and bang it wraps the JSON in a JS callback!

Issues solved. The final part was to mix in a little jQuery to load the JSON+callback feed into a <script> tag and then display it.

Total lines of code: 27 lines of javascript.

EDIT. Now with code!

Hello Android!

In the last few weeks the battle and buzz over the smart phone market seems to have seriously intensified.

First there was the usual iPhone buzz, news about the Android powered HTC Magic, the Windows Mobile marketplace, and of course the obligatory ridiculousness at Microsoft.

I’d been considering experimenting with a mobile platform for sometime and finally decided to take the plunge. I decided to give Android a whirl primarily because I don’t have easy access to OSX or Visual Studio and my Java is less rusty than my .NET.

Anyway, getting going with Android was deliciously simple – download the SDK+Emulator and Eclipse plugin and you’re off.

After the necessary “Hello World” application I tried to write something a bit more substantive. Personally, one of the coolest facets of mobile development is the ability for applications to be location aware (GPS). Mix this together with some openly available geo tagged data and the result is probably going to be interesting.

With this in mind, the plan became to mash together Android’s GPS coordinates with flickr’s geotagged photos.

Getting access to Android’s location service is fairly straightforward. You basically register to receive updates either when the device moves a certain distance or on some time interval:

The biggest “gotcha” with this is that you NEED to remember to modify the default Application security settings to allow you to access the device’s location. In Eclipse, edit AndroidManifest.xml and add “UsesPermission” for the following: android.permission.ACCESS_MOCK_LOCATION, android.permission.ACCESS_COARSE_LOCATION, android.permission.ACCESS_FINE_LOCATION

So on to part II – using the device’s location to pull down Flickr photos. I’d used the Flickr API before so I knew how to do it but I’d never used it from Java. I tried loading the JAR for the flickrj client library but the Android JVM was having some strange issues with it. I was under the impression you can link to external JARs from Eclipse but I may be wrong (anyone?).

Anyway, the Flickr requests were un-authenticated and pretty straightforward so I decided to use Java’s URL class. Accessing sockets was another “gotcha” – Android requires your application to have the “UsesPermission” android.permission.INTERNET to use sockets. The exception when the permission isn’t set is notably cryptic – “unknown error”.

I decided to download all the Flickr photos to the device so that the UX would be generally smoother. This introduced threading to the project so that the UI wouldn’t freeze up while the photos were downloading. Android threads work just like traditional Java threads and the process was generally painless:

With the photos pulled down the final task was displaying them. After poking around the Android documentation I discovered the Gallery widget. It basically allows you to display a set of items in a list and specify a “renderer” for the gallery. I’m not sure if there is a default way to make it “fisheye” (like on an iPhone) but I rolled a quick n dirty solution for that. I also couldn’t get it to look really sexy but that’s also probably possible.

So that’s about it. Here are some screen shots of the application running in the emulator:

And without further a due here is the code as an Eclipse project.
geoflickr

Anyway, before the bashing starts – I know I’m a terrible Java programmer and that this project isn’t really engineered beautifully. It was just supposed to be a way to get my (and anyone else’s) feet wet with Android. Any comments/thoughts/improvements are of course welcome!

Timelapse Twitter+Election map

This is an update to our Twitter+Election ’08 mashup that was over at Setfive Election HQ

Well as everyone saw last Tuesday night, Obama won the election by a pretty significant margin and has all ready taken steps to announce his transition agenda.

Anyway, at the end of our run, we captured 11021 tweets with the breakdown being 2501 for McCain and 8520 for Obama. Since we had been generating maps all day we decided to take snapshots at 5 minute intervals so that we could watch the progression of the map. The timelapse map is embedded below:

We hope everyone had a good election experiance – we had a lot of fun building this mashup. Now to find the next big thing…