calc.java

这是一个用J2ME开发的计算器程序

package Calc;

import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
import java.io.*;

public class Calc extends MIDlet implements CommandListener {
    private Display display;
    private Canv canv;

    private Command cmdexit  = new Command("退出(Exit)", Command.EXIT, 90);
    private Command cmdkey1  = new Command("运算符", Command.OK, 10);
    private Command cmdkey2  = new Command("存储器", Command.OK, 20);
    private Command cmdkey3  = new Command("转换键", Command.OK, 30);
    private Command cmdkey4  = new Command("标准型", Command.OK, 40);
    private Command cmdkeyb  = new Command("功能键盘", Command.OK, 1);
//    private Command cmdleft  = new Command("Left", Command.OK, 2);

    public Calc() {
        display = Display.getDisplay(this);
        canv = new Canv();
        canv.addCommand(cmdkeyb);
        canv.addCommand(cmdexit);
        canv.addCommand(cmdkey1);
        canv.addCommand(cmdkey2);
        canv.addCommand(cmdkey3);
        canv.addCommand(cmdkey4);
        canv.setCommandListener(this);
    }

    public void startApp() {
        display.setCurrent(canv);
    }

    public void pauseApp() {
    }

    public void destroyApp(boolean unconditional) {
        display.setCurrent((Displayable)null);
        canv.destroy();
    }

    public void commandAction(Command c, Displayable d) {
        if (c == cmdexit) {
            destroyApp(false);
            notifyDestroyed();
        } else if (c == cmdkeyb) {
            //canv.removeCommand(cmdright);
            //canv.addCommand(cmdleft);
            canv.setLeftRight();
        } else if (c == cmdkey1) {
            canv.setRight(1);
        } else if (c == cmdkey2) {
            canv.setRight(2);
        } else if (c == cmdkey3) {
            canv.setRight(3);
        } else if (c == cmdkey4) {
            canv.setRight(4);
        }
    }
}