Building Konfabulator Widgets

Widgets can do tons of things. There are widgets out there that tell you your computer's status (CPU usage, battery life, wi-fi strength, etc). There are tons of RSS readers out there, so you can stay ontop of your favorite news feeds. Sports scores. Photos. Yoda giving you his favorite sayings? It's out there already! So, spend a moment thinking about what you want...

Goto the widget gallery (link above). Use some basic search terms to see if your widget exists. If so, you're done - use that widget!

If not, that's where things start to get interesting. There might be a widget out there that is similar but not quite what you're looking for. Download a couple of those widgets and those can be the starting points for your exploration into widget development.

Okay - if you know what your app is and you've got a widget that is close, the best bet is to open it up and tweak it a bit.

The widget converter (link above) is the best bet for opening up the widget. A big advantage to widget development is that it is a pretty open system. No code hoarding (though some could obfuscate...).

So you can dig into the widget and change/improve what you need to pretty easily.

If you don't have a similar widget, well, then you're best off starting with their tutorial and finding out how the framework works. Once you do the "Hello World" you should have a good idea of how to build apps.

The debug cycle is a little rough with Javascript generally, but it's not impossible.

Use the LOG method Konfabulator provides. Its your printf or System.out utility. To enable display of the log methods, use on within your widget tags. Don't forget to turn it "off" before you ship though!

For visual/layout issues, I tend to use baby steps. Don't change several things at once. Make small changes so that if things go wrong, you don't have too many things to check. Visually, it is easy to get things confused with just minor changes (everything within a frame won't appear if the frame isn't set up properly for example).

And for the Javascript issues, well, baby steps again. Some basic tips:

1 - Use Object has a hash, its a convenient flexible data store.

2 - Use methods as much as possible, code-reuse as well as being able to organize the flow of your app.

3 - Use asynchronous file fetching when possible. Synchronous fetches will freeze the widget while waiting for the file.

4 - Use the LOG method - include variables in your messages so that the messages are more useful/informative. Comment out the unneeded log messages instead of deleting them (just in case you need to uncomment them out later).

Share your widget with others. Enjoy the feedback you get on it.

Don't take it too personally if people have suggestions. It means they like your widget enough to use it, and would enjoy it even more if it had feature X.

Pat yourself on the back - job well done.

And now go add feature X...