CTO, Software engineer and Team leader
Archive for June, 2009
Objective-C: NSDictionary and NSMutableDictionary can’t keep the order of entries
Jun 30th
My latest task in CSCW Lab was to create the parser class for parsing some huge and multilevel XML. All nice and easy at first sight. Since the XML was the result of an RPC call, I got back some structures corresponding to NSDictionary and some arrays corresponding to NSArray in Apple’s Objective-C.
While iterating in the structure using NSXMLParser, a event-based parser, I kept adding the pairs as name and values to the parent.The normal approach would be to add the name and NSNull for value first, then when retrieving the value’s content, search the last inserted entry ( the More >
Objective-C: UIAlert or asking for confirmation
Jun 29th
While start XCoding, I faced a new challenge : how to create modal, single use confirmation dialogs? So after some digging in the internet, I found out that this can be actually done pretty simple and elegant. This will be very useful if you want to display some deletion confirmation or ask for user permission to use the camera or GPS sensor. All you have to do is just create a UIAlert and the IBAction hooked up to your “Nuclear launch” button, and then have its delegate decide whether to destroy the world or not.
In the header file you have to More >
UIImageView setImage problem
Jun 28th
While working for this semester’s CSCW lab project, I encountered a strange situation: no matter what I did, the UIImageView didn’t load the image. After some digging on the Internet about this, I found out that first thing to look for is whether you’re sending the setImage message to the UIImageView instance you expect.
Being newbie in XCode and Apple’s technologies in general, I forgot to use NSLog. So my advice is to check and check often with NSLog for a nil pointer in the same place you’re trying to set the image. Obj-C loves to make freshman crazy by sending More >
Programming languages and sensors
Jun 20th
For the moment we expect to use either one of those strategies to implement our idea
1.Use Wiimote, an iphone, and a skateboard for implementing this game .
- Wiimote : as sensor for capturing the type of movement that is currently implemented.
- iPhone : read the sensed values from Wiimote and implement Game Interface
- Expected Language for implementation : Objective C .
2. Use iPhone , and adruino board that enables wireless communication with the following sensors:
- Bending sensor.
- Accelarometer.
- Expected Language for implementation : Objective C , and C++
New team created for DIS2 Project
Jun 17th
We are proud to announce that we created a team that will accept the challenge of the DIS 2 Project: design an Exertion Game.
The team is formed by:
- Loredana Ene – 286052
- Fariha Atta
- Poenaru Radu – 286053
- Abd al Rahman
We are students of RWTH Aachen, learning in Bonn-Aachen International Center for Information Technology in Bonn.
[Note: Here I will present my work, the entire project can be found on http://dis2project.blogspot.com]
Xcode – String concatenation
Jun 6th
Don’t be fooled that Objective-C is a Object oriented language. For decades operators overloading is something standard in almost all of them.
But in Objective-C you don’t have it. Mostly, I believe that comes from the struggle of Apple guys to assure the stability of the system. A lot of errors can come from poorly designed overloads, thus the crashes can appear.
Now let’s put some hands on code.
In C, Java or Pascal you would have written something like the following for string concatenation:
string1 = string2 + string3;
But in Objective-C you need to do something different:
NSString *myString = @"http://www.mywebsite.com"; float myValue = More >
Forecast on websphere: Flex or Silverlight or AJAX or JavaFX ?
Jun 5th
Lately I had some interesting conversations with few of my developer friends regarding their opinions on which technology will rule the Rich Application Interfaces websites in the future. My strong believe is that there’s room for all four of these as per my experience and actual trends. More over, all these will have a separate slice of the market but overlap at only few areas. Let’s take AJAX as example – it is widely popular for creating rich user experience community building apps, portals, mash-ups and so on. On the other hand, Flex is used more for multimedia rich More >
