barcodereader.java

this small program about implement barcodes in mobile phone

package barcodereader;

import java.io.IOException;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;

public class BarcodeReader extends MIDlet{
    public Display display;
    public Image background, buffer;
    public Graphics graphics;
    public Font font;
    public MainMenu mainmenu;
    public int heightoffset, bufferwidth, bufferheight, width, height, 
        halfwidth, halfheight, fontheight; 
    private SplashScreen splashscreen;
    
    public BarcodeReader() {
        display = Display.getDisplay(this);
        
        try{
            background = Image.createImage(getClass().getResourceAsStream(
                "/image/background.PNG"));
        }
        catch(IOException ioe) {
            ioe.printStackTrace();
        }
        
        heightoffset = 22;
        buffer = Image.createImage(176, 220);
        graphics = buffer.getGraphics();
        bufferwidth = buffer.getWidth();
        bufferheight = buffer.getHeight();
        graphics.setFont(Font.getFont(Font.FACE_SYSTEM, Font.STYLE_PLAIN, 
            Font.SIZE_SMALL));
        font = graphics.getFont();
        fontheight = font.getHeight();
        
        splashscreen = new SplashScreen();
        mainmenu = new MainMenu(this);
    }
    
    public void startApp() {
        splashscreen.setFullScreenMode(true);
        display.setCurrent(splashscreen);
        
        try{
            Thread.sleep(3000);
        }
        catch(InterruptedException ie) {
            ie.printStackTrace();
        }
        
        mainmenu.setFullScreenMode(true);
        display.setCurrent(mainmenu);
    }
    
    public void pauseApp() {
        
    }
    
    public void destroyApp(boolean unconditional) {
        
    }
    
    private class SplashScreen extends Canvas{
        private Image splashscreen;
        
        public SplashScreen() {
            width = getWidth();
            height = getHeight();
            halfwidth = width/2;
            halfheight = height/2 + heightoffset;
            
            try{
                splashscreen = Image.createImage(getClass().getResourceAsStream(
                    "/image/splashscreen.PNG"));
            }
            catch(IOException ioe) {
                ioe.printStackTrace();
            }
        }
        
        public void paint(Graphics g) {
            graphics.setColor(0, 0, 0);
            graphics.fillRect(0, 0, bufferheight, bufferwidth);
            graphics.drawImage(splashscreen, 0, 0, 
                Graphics.LEFT | Graphics.TOP);
            
            g.setColor(0, 0, 0);
            g.fillRect(0, 0, width, height);
            g.drawImage(background, halfwidth, halfheight, 
                Graphics.HCENTER | Graphics.VCENTER);
            g.drawImage(buffer, halfwidth, halfheight, 
                Graphics.HCENTER | Graphics.VCENTER);
        }
    }
}