Been a long time since I have updated this little project of mine. Yep, just checked, its been almost a year since.

Oddly enough this is one of my projects I actually use on a daily basis at home and work. Im not sure why I haven’t updated it since as there have been some rather gaping bugs in it which have been very annoying but apparently not annoying enough to encourage myself to fix them or to stop using it.

Anyways, I have finally decided to fix some of the most anoying issues namely:

• It no longer crashes when the network is lost
• It now correctly reports the amount of physical memory used

Theres no auto-updating feature built into the tool so if you are looking for the upgrade head over to the google code page to grab it: http://code.google.com/p/win7-taskbar-mon/downloads/list

Wow! Just noticed that over 2000 people have downloaded the first version, didn’t think it was that popular!

Oh yes, I have also uploaded the latest source for this version: http://code.google.com/p/win7-taskbar-mon/source/checkout

Enjoy!

In this post I talk about the challenge of device discovery and networking in the Inputtie app.

Zero Configure Networking

I knew I wanted Inputtie to be as simple to get running as simply starting it up. For this to happen Inputtie would need to discover all other devices on the network also running Inputtie. So how to do this?

Well, as it happened I had been reading at the time about Apple’s Bonjour which was designed to do just what I needed. It is a combination of a multi-cast and DNS lookup service that allows it to detect other Bonjour capable devices on the network. Sounds perfect.

So I got to work on implementing their Java API. After many trials and tribulations I eventually had it working.. kinda. It was detecting other devices sure, but every now and then it would sporadically disconnect from the network. I couldn’t for the life of me work out why. I posted on forums and even tried to read the reams of source to see what was going on but alas to no avail.

After much deliberation I decided to look for another solution to the problem of Zero Conf. networking. Next up were a whole host of other attempts. I tried JmDNS which is was supposedly very similar to Bonjour. I also experimented with JGroups. I had limited success with all of them and in the end only really succeeded in wasting several months worth of development time.

The Solution

In the end the solution (and the one currently employed in Inputtie) was the simplest. After months of messing around with these libraries I had learnt quite abit about how they performed their magic. At the heart of it they either used multi-cast or broadcasting to announce a device on a network. Broadcasting can be thought of as a sort of sonar pulse. The broadcasting computer sends a message on a specific IP address then another device listens for the message and proceeds to open a Socket for a more private form of communication. From Wikipedia:

A broadcast address is a logical address at which all devices connected to a multiple-access communications network are enabled to receive datagrams. A message sent to a broadcast address is typically received by all network-attached hosts, rather than by a specific host.

I decided that if these libraries could use broadcasting for discovery then so could I and if I wrote it myself I could keep it simple. So I set to work coding an example in Java. In no time at all I had it running and surprisingly it worked! Sure it wasnt as robust as the established libraries, it didn’t handle devices disconnecting from the network, different network subnets or IPv6 but it was simple and at least it worked!

Broadcasting in Adobe AIR

As I mentioned in a previous post Inputtie went through many re-writes during development from its original form in Java through C++, C Sharp and finally Adobe AIR. With the latest (it was still in beta when I started development) version of Adobe AIR 2.0 several new APIs were made available for use, one of them being new classes designed specifically for peer to peer (P2P) networking. With these new APIs I believed I should be able to implement network broadcasting much in the same was I was doing in Java. Unfortunately however it seemed that Adobe was restricting the use of broadcast to their new P2P service Cirrus.

There was however another crucial API released with AIR 2.0; the NativeProcess API. With this a developer is able to easily execute and communicate with a program written in another language. What this meant for Inputtie was that I could write the user interface in AIR and then use NativeProcess to call Java code that would perform actions not available in AIR, such as Broadcasting. (incidentally it also is a great way to do multi-threading in Air )

So the current solution in Inputtie is to use NativeProcess from AIR to communicate with a small headless (no user-interface) Java process that does the broadcasting and listening for broadcasts. Once the Java process detects an incoming broadcast it passes the information back to AIR.

EDIT: If anyone is interested in seeing the source to my previous (failed) attempt just drop me a comment or an email and I would be happy to share.

A while back, I had an idea for a very simple application that would sit in your taskbar and give you at-a-glance performance info about your system, similar to iStat Pro for OSX. This weekend I finally had time to clean up the code up for release.

The problem is that while looking for a couple of images for the app I happened to stumble across Taskbar Meters, which is pretty much the exact same idea I had. Looks like he has made a better job out of it that me too

Ah well, I have decided to release my version of the app nonetheless:

You can open the app multiple times and set each one to monitor a different value:

I have also decided to post the source up on google code: http://code.google.com/p/win7-taskbar-mon/

Anyways you can grab version 0.1 here: http://win7-taskbar-mon.googlecode.com/files/Windows7_Taskbar_Monitor_v0.1.zip

Screenshot

DLL
http://www.mikecann.co.uk/Files/GoToDefinition.dll

Source
http://www.mikecann.co.uk/Files/GoToDefinition_source.zip

Post
http://www.flashdevelop.org/community/viewtopic.php?f=4&t=4722

EDIT:
It appears that the same functionality is built as standard into FD with the use of the F4 key. Oh well, you can still use this as a shortcut

Its an excellent upgrade and brings some extra features that were lacking in my very basic version.

Copy / Paste of his update:

Liked the plugin so much I decided to add a few features! Posting here with Mike’s permission.

Screenshot

Updates
Added 4 plugin setting options:

Highlight Color (Choose a color for the highlight)
Highlight Whole Words (Choose whether to highlight whole words only or include partial text)
Match Case (Choose whether to match the case of the selection or not)
Add Line Marker (Display a line marker next to highlighted text)

No longer highlights white-space characters

Installation
+ Open FlashDevelop, Click Tools -> Application Files
+ Copy the DLL to the “Plugins” directory
+ Restart FlashDevelop

DLL
http://gonegothic.com/files/flashdevelo … ection.dll

Source
http://gonegothic.com/files/flashdevelo … ection.zip

After a few evenings work however I decided that this project was going to take up a bit too much of my time, especially when I had so much other work to do. So I have decided to release what I have done and let other take it and develop it if they wish.

You login using a twitter account:

Once logged in you are presented with the main interface, plugins are loaded automatically from the directory and displayed as tabs. The reason for doing them as plugins is to allow users to pick and choose what functionality they want their twittbot to have. Also it allows for easy upgrading to newer plugin versions.

Hangman was the primary idea for this project and is implemented as a simple plugin that consists of 3 simple commands:

I have built a simple polling timer for checking new messages from Twitter:

The interface uses docking panels provided by the .NET DockPanel Suite. Docking is demonstrated below with the log window:

The next shot shows me sending a direct message to the “twittgames” account from my “mikeysee” account:

After refreshing, the Hangman plugin then shows the active game states:

Then you play the game by making guesses:

A

And the plugin responds to your guesses:

It is far from complete but as a proof of concept I think it demonstrates the idea. There are many things that could be improved and/or worked upon, such as:

• Implement async calls rather than halting the thread when making a call
• Completing the Auto-follow plugin
• Implementing a database to log previously handled messages
• Enable back-messaging so you can search for previous messages and handle them
• Implement an interface for loading/unloading plugins

For the technology side of things, its was developed in C# .NET 3.5 using the excellent TweetSharp library for interfacing with Twitter. Docking panel functionality is provided by DockPanel Suite.

You can grab the binary for this here: TwitterBot.zip

Source code is available on request. Email: mike.cann@gmail.com

Just to follow on from the previous post and to make it make a little more sense, here is a screenshot of the demo XNA space game i made in a day to show off my new particle engine SDK.

Yup space penguins are attacking the earth!