Tuesday, May 16, 2006

Social Networking / Cell Phones


Here's a biased article I read recently about social networking sites. About halfway through they talk about expansion to cell phones battling eventual product abandonment. Interesting argument.

Assisted GPS

So I was looking around the internet a little bit and came across this interesting article about GPS on phones and the introduction of "assisted GPS" that I thought others in the class might be intersted in reading.


Tuesday, May 02, 2006

Reading and Writing files to the SD card on the a780

Just in case you needed to read/write files to the SD card on the a780, I just came across how to do that today. It's not really documented anywhere although if you use the "listRoots()" method you can find it out. Note that it's "SD" and not "SDCard" as the JSR would lead you to believe.

FileConnection sc = (FileConnection)Connector.open("file:///SD/myFile.txt");
OutputStream os = sc.openOutputStream();

Friday, April 28, 2006

emulator issues

has anyone had this error before when trying to run the emulator: (the emulator had worked at the beginning of the session)

java.lang.NoClassDefFoundError: TestMIDlet
at com.sun.midp.midlet.MIDletState.createMIDlet(+14)
at com.sun.midp.midlet.Scheduler.schedule(+52)
at com.sun.midp.main.Main.runLocalClass(+29)
at com.sun.midp.main.Main.main(+88)

Anyone know what going on here?

Thursday, April 20, 2006

MoSoSo resources...

I just wanted to forward on to you a list of "useful resources" compiled by the participants of the Mobile Social Software workshop at CHI this year. As you guys start to think about your final reports, you might find some of these helpful. A lot are overlap from the list I put together on the course home page, but many are new.

Monday, April 17, 2006

Stylus Event and Key Events

This is how you can read stylus events, i.e. get the x,y coordinates of where the pointer is pressed and how to create a key event, i.e. read what button the user has pressed:

In order to draw stuff on screen you'll either use Canvas, LWT or GameCanvas. As LWT and GameCanvas both extend Canvas, you can just implement a key and stylus listener.

Just implement the following methods in your class that draws stuff on screen, i.e. extends an interface mentioned above: (this is an extract from our code, you can implement your own handling)

//this method will be called if the stylus touches the screen at x,y:
protected void pointerPressed(int x, int y) {
//do something with the received x,y coordinates
current.actionPerformed(new Message(Message.STYLUS, x,y));

//this method will be called if the user presses a key
protected void keyPressed(int keyState){

//determine whether the input is something we can use or not.
boolean flag = true;

case -3:
keyState = LEFT_PRESSED;
case -4:
case -1:
keyState = UP_PRESSED;
case -2:
keyState = DOWN_PRESSED;
case -5:
keyState = FIRE_PRESSED;
flag = false;
//if the data is good, perform the according action
current.actionPerformed(new Message(Message.JOYSTICK, keyState));

Thursday, April 13, 2006

Google Calendar

For those looking for a calendar with a nice open API, google just launched Google Calendar today. It provides iCal and XML feeds for your calendar and lets you subscribe to other people's calendars as well.

Wednesday, April 12, 2006

EclipseME setup and other common problems

Hey everyone, since so many people had problems getting EclipseME to work I'm posting a troubleshooter here.

Tuesday, April 11, 2006

Fullscreen Application

Is there any way to make a Java application full screen? I.e. hide the standard phone icons on top and the grey bar on the bottom?

Monday, April 10, 2006

calendar on A780?

does anyone know how to access calendar on A780? I know that there is a program called calendar on it, but I was wondering if there is any JAVA API that allows developers to access calendar functions on the phone.

Wednesday, April 05, 2006

Detecting Stylus Event?

Does anyone have some sample code of how to get the stylus position on the touch screen if the user taps on the screen? I only found out how to use the joystick and other buttons so far.

Monday, March 27, 2006

Easy tu use GUI designer for J2ME

I found this GUI design application called J2ME Polish J2MEPolish.org

Thus appears to be a very nice GUI designer. Has anyone vas tried it out?

Friday, March 24, 2006

Software turns laptops into navigators

Software turns laptops into navigators
Loki system melds global positioning, WiFi to find services -- from Boston GLOBE
A Boston company is giving away software that can turn nearly any laptop computer into a global positioning system, enabling users to find the nearest restaurant, hospital, or gas station at the touch of a button.

Wednesday, March 22, 2006

Social Network Service Parody

The other end of the spectrum:


Tuesday, March 21, 2006

6.883 Class on Cell Phone Computing

Course 6 has a class this semester with a lot of useful info on GPS, Cell tower tracking, etc.


They also have a class wiki with a lot of pertinent topics: