如何在 Java ME 中向用户询问一些号码？

Question

我对 Java Me 很陌生（第一次）。我希望我的程序向用户询问 IP 地址。 0 到 255 之间的四个数字。这并不困难，但正如我所说，我是 Java Me 的新手。

Answer 1

您希望用户如何输入IP地址？例如，您想使用 TextField 吗？您可以执行以下操作：

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

public class GetIPAddress extends MIDlet implements CommandListener {

  private Display display;
  private Form form = new Form("IP Adress Input");
  private Command submit = new Command("Submit", Command.SCREEN, 1);
  private Command exit = new Command("Exit", Command.EXIT, 1);

  private TextField textfield = new TextField("IP Address:", "", 30, TextField.ANY);

  public GetIPAddress() {
    display = Display.getDisplay(this);
    form.addCommand(exit);
    form.addCommand(submit);
    form.append(textfield);
    form.setCommandListener(this);
  }

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

  public void pauseApp() {
  }

  public void destroyApp(boolean unconditional) {
  }

  public void commandAction(Command command, Displayable displayable) {
    if (command == submit) {
      // Do the manipulation of the IP address here. 
      // You can retrieve it using textfield.getString();
      form.removeCommand(submit);
    } else if (command == exit) {
      destroyApp(false);
      notifyDestroyed();
    }
  }
}