Question

J2ME 一个小程序的错误

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.TextBox;
import javax.microedition.midlet.MIDlet;

public class exit extends MIDlet implements CommandListener {
private Display display;
private Command c;
private TextBox t;
public exit() {
display=Display.getDisplay(this);
t=new TextBox("asdfsd","sdfsf",0,0);
c=new Command("退出",Command.EXIT,1);
t.addCommand(c);
t.setCommandListener(this);
}

public void destroyApp(boolean arg0) {

}

public void pauseApp() {

}

public void startApp() {
display.setCurrent(t);

}

public void commandAction(Command arg0, Displayable arg1) {
if(arg0==c){
destroyApp(false);
notifyDestroyed();
}

}

}

Answer 1

new TextBox("asdfsd","sdfsf",0,0); 中的第三个参数必须是一个大于0的数，字符的最大长度怎么能是0呢？好好看一下API文档。