Objects. Phone. Programming. Mobile DAY 3 J2ME. Module 2. In real world: object is your car, your bicycle, your cat.. Object has state and behavior

Size: px

Start display at page:

Download "Objects. Phone. Programming. Mobile DAY 3 J2ME. Module 2. In real world: object is your car, your bicycle, your cat.. Object has state and behavior"

Elfrieda Sims
6 years ago
Views:

cat.. Object has state and behavior State: variables (car: color, model)

1 DAY 3 J2ME Mobile Phone Programming Module 2 J2ME DAY 3 in aj2me nutshell Objects In real world: object is your car, your bicycle, your cat.. Object has state and behavior State: variables (car: color, model) Behavior: methods (car: accelerating, braking) Object is created by using class 1

2 Class In real world: all cars have some state and behavior in common Class defines the variables and the methods common to all objects of a certain kind Defining object Dog Billy; Creating object Billy = new Dog(); Object-Oriented Programming Fundamentals public class Car int MaxSpeed; public void speed_up() #code for speeding up Car Corvette = new Car(); Corvette. MaxSpeed =280; Corvette. speed_up() ; Car Ferrari = new Car(); Ferrari. MaxSpeed=320; Ferrari.speed_up(); DAY 3 J2ME If-Then Statement: if ( boolean Expression ) //code If-Then-Else Statement: if ( boolean Expression ) //code else if ( boolean Expression ) //code else //code 2

3 for Statement: for (i = 0; i < 10; i++) //code while Statement: while (boolean expression) //code [iteration;] DAY 3 J2ME Switch Statement: switch (variable) case value_1: //code (only one line); break; case value_2: //code (more than one line); break; GUI Instead of dividing the display into multiple windows (like MS Windows), the GUI could be seen as a deck of screens - only one active at a time Display has a single, fixed-size window whose content are controlled by one application at any time MyMIDlet YourMIDlet 3

4 GUI High-level API Portability key issue Easy-to-use Little control over GUI s look and feel Low-level API Full control of graphics elements and low-level input events Four classes: Canvas, Graphics, Image, Font Game API provides additional classes for low-level drawing Major Classes of LCDU - MIDP 1.0 Display Displayable Screen Canvas ChoiceGroup DateField TextBox Gauge Alert List Ticker ImageItem StringItem Form Item TextField Major Classes of LCDUI - MIDP 2.0 Display Displayable CustomItem Spacer Screen TextBox Alert List Form Canvas Ticker Item ChoiceGroup DateField Gauge ImageItem StringItem TextField 4

5 TextBox public class TextBox_Example extends MIDlet //TextBox(,text,size,contrains) TextBox textbox = new TextBox("Text Box Example","This is an example of a TextBox",50,0); display.setcurrent(textbox); Alert public class Alert_Example extends MIDlet // Alert(label,text,Image,type) Alert alert= new Alert("Error Alert","This is an Error Alert example",null,alerttype.error); alert.settimeout(alert.forever); display.setcurrent(alert); List 1 public class Multiple_List extends MIDlet //List(label,type,items,Images) List list = new List("Multiple list", List.MULTIPLE,new String[] "Python", "J2ME", "Symbian", null); display.setcurrent(list); 5

6 List 2 public class Implicit_List extends MIDlet //List(label,type,items,Images) List list = new List("Implicit list", List.IMPLICIT,new String[] "Python", "J2ME", "Symbian", null); display.setcurrent(list); List 3 public class Exclusive_List extends MIDlet //List(label,type,items,Images) List list = new List("Exclusive list", List.EXCLUSIVE,new String[] "Python", "J2ME", "Symbian", null); display.setcurrent(list); Empty Form public class Empty_Form extends MIDlet Form form = new Form("Empty Form"); 6

7 Form with ChoiceGroup 1 public class Choice_Group extends MIDlet Form form = new Form("Form example"); //ChoiceGroup(label,type,elements,image) ChoiceGroup CourseEXCL = new ChoiceGroup ("Exclusive choice", Choice.EXCLUSIVE,new String[] "Python", "J2ME", "Symbian", null); form.append(courseexcl); ChoiceGroup CourseMULT = new ChoiceGroup ("Multiple choice", Choice.MULTIPLE,new String[] "Python", "J2ME", "Symbian", null); form.append(coursemult); Form with ChoiceGroup DAY 3 J2ME 2 public class Choice_Group extends MIDlet Form form = new Form("Form example"); //ChoiceGroup(label,type,elements,image) ChoiceGroup CoursePOP = new ChoiceGroup ("Pop Up choice", Choice.POPUP,new String[] "Python", "J2ME", "Symbian", null); form.append(coursepop); Form with DateField public class Date_Field extends MIDlet Form form = new Form("Form example"); // DateField(label,type); DateField datefield = new DateField("Date Field Example", DateField.DATE_TIME); form.append(datefield); 7

8 Form with Gauge public class Gauge_ex extends MIDlet Form form = new Form( Gauge example"); //Gauge(label,interaction,maxValue,InitialValue) Gauge gauge = new Gauge("Gauge example", false, 20, 4); form.append(gauge); Form with ImageItem import java.io.ioexception; public class Image_Item extends MIDlet Form form = new Form("Form example"); try Image Logo = Image.createImage("/images/logo.png"); //ImageItem(label,Image,layout,alternative text) ImageItem imageitem =new ImageItem("ImageItem Example",Logo,ImageItem.LAYOUT_CENTER,""); form.append(imageitem); catch (IOException ex) System.out.println("Exception occurred: "+ex); Form with StringItem public class String_Item extends MIDlet Form form = new Form("Form example"); // StringItem(,text) StringItem stringitem= new StringItem("String Item", "This is an example of StringItem"); form.append(stringitem); 8

9 Form with TextField public class Text_Field extends MIDlet Form form = new Form("Form example"); // TextField(label,text,size,constrains); TextField textfield =new TextField("TEXT FIELD","",25,TextField.ANY); form.append(textfield); Canvas public class Canvas_Example extends MIDlet CanvasDemo canvas = new CanvasDemo(); display.setcurrent(canvas); class CanvasDemo extends Canvas public void paint (Graphics g) g.setcolor(50,50,255); g.fillrect (0, 0, getwidth (), getheight ()); g.setcolor(200,200,200); g.drawstring("example of Canvas",0,20,0); g.setcolor(0,0,100); g.drawline (0, 40, 100, 200); g.setcolor(200,0,0); g.fillrect (50, 70, 80, 50); Adding Command Buttons import javax.microedition.midlet.midlet; public class Command_ex extends MIDlet implements CommandListener Command ExitCmd = new Command ("Exit",Command.EXIT,7); Command CheckCmd = new Command ("Check",Command.SCREEN,1); Form form = new Form("Commands example"); form.append("this is a Command button example. Please press the Check button "); form.addcommand(exitcmd); form.addcommand(checkcmd); form.setcommandlistener(this); public void destroyapp(boolean unconditional) notifydestroyed();. public void commandaction(command c, Displayable d) if (c==exitcmd) destroyapp(true); else if (c==checkcmd) Alert alert = new Alert("Alert"); alert.setstring("check button test"); alert.settimeout(3000); // 3 seconds display.setcurrent(alert, display.getcurrent() ); 9

10 Developing DAY Your3 Applications J2ME Application development SDK and development tools installation Application development Target your users What kind of application do you want to develop? On which platform? (MIDP 1.0 or MIDP 2.0) Which tools do you need? How to get started? Development tools The following software needs to be installed on your PC: Java Development Kit (JDK) IDE (Integrated Development Environment) NetBeans Eclipse Carbide.j 10

dk/teaching/free_study_activities/mobile_phone_programming_spring_2007/ DAY 3 J2ME JDK = Java Development Kit - if you want to develop or just

11 SDK and development tools Our suggestion is to install the following software on your PC: J2SE Netbeans 5.5 (IDE) Netbeans 5.5 mobility Pack All the files can be downloaded from: DAY 3 J2ME JDK = Java Development Kit - if you want to develop or just compile Java programs (*.java -> *.class -> *.jar) JRE = Java Runtime Environment - if you want to execute a Java program Installing J2SE Run the file: jdk-6-windows-i586.exe Follow the instructions for the installation 11

12 NetBeans 5.5 (IDE) The NetBeans IDE is an opensource integrated development environment written entirely in Java NetBeans contains all the modules needed for Java development in a single download, allowing the user to start working immediately. Installing NetBeans 5.5 Run the file netbeans-5_5-windows.exe Follow the instructions for the installation NetBeans 5.0 Mobility Pack The NetBeans Mobility Pack is a Plug-in of NetBeans IDE that can be used to write, test, and debug applications for the Java 2 Micro Edition technology-enabled mobile devices. The NetBeans Mobility Pack integrates support for: Mobile Information Device Profile (MIDP) 2.0 Connected, Limited Device Configuration (CLDC) 1.1 You can easily integrate third-party emulators for a robust testing environment. 12

13 Installing NetBeans 5.0 Mobility Pack Run the file: netbeans_mobility-5_5-win.exe Follow the instructions for the installation Resources NetBeans Demonstration 13

Mobile Phone Programming

Mobile Phone Programming Free Study Activity Day 3 Part 2 J2ME in a nutshell J2ME in a nutshell Objects In real world: object is your car, your bicycle, your cat.. Object has state and behavior State: