Saturday, December 22, 2007

Never miss the bus again with Plasma

On Thursday I had a meeting with my classmates from the advanced chemistry course, some of them I haven't seen since 6 years, that was real fun! What has this information to do with KDE? Well, on the way to the Irish pub we used the bus of our local public transport (DVB). They have nice info screens (running windows, so you often see just a bluescreen ;)) with advertisement on it. These evening the showed information about a 'widget' that you can download to show the arrival/departure times of a single bus/tram stop. The next day I browsed the DVB website and found a link to this widget, it is a Yahoo Widget thingy... unfortunately the Yahoo Widget engine is not available for Linux :(

Ok, I'm a hacker, let's see whether we can fix that!

The Yahoo Widget consists of a couple of HTML, image and JavaScript files, packed into a proprietary format. Finding out the URL queried by widget to retrieve the information was no problem and the returned data are in an easy to parse format. So the rest of the work was to assemble a Plasmoid which makes use of these 'webservice'. Two days later (had to buy some xmas presents in the meantime ;)) there is a working version available:

You can see two applets which show the departure time for two different stops.
Of course this Plasmoid is only useful for all KDE users living in Dresden (maybe 10? ;)) so I'll make the code available on my private website only, or provide it by KNewStuff later.

Update: You can find the sources and the compile instructions now under

Tuesday, November 13, 2007

Plasma goes userfriendly (III)

University consumes a lot of time these days, however there are always some minutes for continue hacking on the comic plasmoid. During the last days I cleaned up the code and added nicer buttons with icons, which appear on hovering the plasmoid. As we have support for a new comic strip ( now, there was the need for easy configuration. You can see in the screenshot the new configuration dialog, where you can select the comic to show. Currently the selection is hard-coded, however in future versions it shall query the supported comics from the comic engine directly.

Friday, November 9, 2007

Plasma goes userfriendly (II)

During the last two days I extended the userfriendly plasmoid to show not only the comic strip from but also other comic strips (e.g. dilbert or garfield). As the name doesn't match any longer I renamed to to 'comic' plasmoid. The code is still located in playground, however after some more code cleanup and adding a configuration dialog I'll move it to extragear as suggested by Aaron (@Aaron: thanks for the flowers by the way :)). Below you can see the obligatory screenshot of the current state:

As you can see the applet provides buttons (yeah, they look ugly, better ideas or code is welcome ;)) now, which you can use to browse all comics of the past week.

Monday, November 5, 2007

Plasma goes userfriendly

After the organization of the 5. Linux-Info-Tag in Dresden is over now I used this evening to relax a bit and implementing an nice idea I had some weeks ago: Why not creating a plasmoid which shows you the comic cartoon of the day?

Although I'd taken a look at the plasma API several times I didn't do any development, but today I wrote my first plasmoid. As many other developer have already proven, it's quite simple and makes fun. The result of my hack session you can see on the image below.

The code for the engine and the applet is in playground already.
Have fun testing it!

Friday, September 7, 2007

Marble improvements

During the last week I worked in Mönchen- gladbach to earn some money for my daily life ;)

One of my co-workers, most of you known him as tackat aka 'The Marble fame', bugged me every evening to help him improving Marble, so yesterday and the day before I stayed at the office till 23:00 o'clock and helped him to get Marble into a good shape for KDE 4.

The first change was refactoring it into a KPart, so now you can embed it into any other application you like. The second change was a rewrite of the storage backend for map tiles and webpages from wikipedia. Now a cache is used for the webpages, so you can read the city descriptions in an offline version.

The third improvement was a cleanup of the TinyWebBrowser, which is used to browse the city information webpages from wikipedia. 3 days ago it just showed an ugly version of the HTML site. Now it displays images, handles stylesheets and takes care of UTF-8 encoded documents.

As you can see in the screenshot it looks much better now ;)

@pinotree I hope this compensates my absence from Okular hacking :)

Wednesday, May 23, 2007

ODF sprint and Okular

Finally I managed to get a blog account and register it on, so now I'm part of the blogger community as well :)

This time I'll talk about the ODF meeting in Berlin two weeks ago. The KOffice developer invited me as representative for Okular, KDE's unified document viewer.

Our goal of the meeting was to define a way how to share the ODF loading and rendering code of KOffice with an Okular plugin, so that Okular can view any ODF document with the same quality as KOffice. The plan is to use the Flakes API for loading and rendering. However, to make use of this API it must be part of a separated library, which won't happen befor KDE 4.0.

To summarize the meeting in short: We have a clear roadmap now how to integrate advanced ODF support into Okular, but it will still take a while ;)

Nevertheless the meeting gave me the time to start writing a HOWTO about implementing Okular plugins. You can find it here and should give it a read if you plan to extend Okular's support for new fancy document formats. The HOWTO is not finished yet, but it explains how to implement a basic plugin. For an advanced plugin you should take a look at the source code of the existing plugins.