linedemo.java

在手机上实现画线功能

import java.lang.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.MIDlet;

public class LineDemo
    extends MIDlet
    implements CommandListener{
    	public static Display display;
      public Command back1,back2;
      public LineCanvas lc;
      public Form f;
      TextField X[]=new TextField[5],Y[]=new TextField[5];
      int x[]=new int[5],y[]=new int[5];
   public LineDemo(){
    display = Display.getDisplay(this);
    lc = new LineCanvas(this);
    f = new Form("输入坐标");
    for(int i=0;i<5;i++){
    	x[i]=0;
    	y[i]=0;
    	X[i]= new TextField("X"+i,"",8,TextField.NUMERIC) ;
    	Y[i]= new TextField("Y"+i,"",8,TextField.NUMERIC) ;
    	f.append(X[i]);
      f.append(Y[i]);
    }
    back2 = new Command("退出", Command.EXIT, 1);
    f.addCommand(back2);
    back1 = new Command("确认", Command.SCREEN, 0);
    f.addCommand(back1);
    f.setCommandListener(this);
    }
      public void getnum(){
      	for(int i=0;i<5;i++){
      	if(X[i].getString().equals("")||Y[i].getString().equals("")){
      	}else{
      		x[i]= Integer.parseInt(X[i].getString());
      		y[i]= Integer.parseInt(Y[i].getString());
      	}
      	}
      }
      public static void show(Displayable s) { 
        display.setCurrent(s);                 
      }                                        
      public void commandAction(Command c, Displayable d){
      	if(c==back1){
      		getnum();
      		show(lc);
      	}else{
      		destroyApp(false);
          notifyDestroyed();
      	}
      }
      protected void startApp(){
      	show(f);
      }
      protected void destroyApp(boolean unconditional) {

    }

 

    protected void pauseApp() {

    }
    }