如何停止显示多个对话框？

let dialogOpen = false;

function showDialog() {
  if (!dialogOpen) {
    dialogOpen = true;
    alert('This is a dialog box.');
    dialogOpen = false;
  }
}

import tkinter as tk

dialog_open = False

def show_dialog():
    global dialog_open
    if not dialog_open:
        dialog_open = True
        root = tk.Tk()
        root.withdraw()
        tk.messagebox.showinfo('Dialog Box', 'This is a dialog box.')
        dialog_open = False
        root.destroy()

import javax.swing.JOptionPane;

public class DialogExample {
    private static boolean dialogOpen = false;

    public static void main(String[] args) {
        showDialog();
    }

    public static void showDialog() {
        if (!dialogOpen) {
            dialogOpen = true;
            JOptionPane.showMessageDialog(null, "This is a dialog box.");
            dialogOpen = false;
        }
    }
}