import tkinter as tk
from tkinter import messagebox

class CreateToolTip(object):
    def __init__(self, widget, text='widget info'):
        self.waittime = 500     #miliseconds
        self.wraplength = 180   #pixels
        self.widget = widget
        self.text = text
        self.widget.bind("<Enter>", self.enter)
        self.widget.bind("<Leave>", self.leave)
        self.widget.bind("<ButtonPress>", self.leave)
        self.id = None
        self.tw = None
    def enter(self, event=None):
        self.schedule()
    def leave(self, event=None):
        self.unschedule()
        self.hidetip()
    def schedule(self):
        self.unschedule()
        self.id = self.widget.after(self.waittime, self.showtip)
    def unschedule(self):
        id = self.id
        self.id = None
        if id:
            self.widget.after_cancel(id)


    def showtip(self, event=None):
        x = y = 0
        x, y, cx, cy = self.widget.bbox("insert")
        x += self.widget.winfo_rootx() + 25
        y += self.widget.winfo_rooty() + 20
        self.tw = tk.Toplevel(self.widget)
        self.tw.wm_overrideredirect(True)
        self.tw.wm_geometry("+%d+%d" % (x, y))
        label = tk.Label(self.tw, text=self.text, justify='left',
                       background="#ffffff", relief='solid', borderwidth=1,
                       wraplength = self.wraplength)
        label.pack(ipadx=1)
    def hidetip(self):
        tw = self.tw
        self.tw= None
        if tw:
            tw.destroy()
if __name__ == '__main__':
    root = tk.Tk()
    def caixa1():
        tk.messagebox.showinfo("Saudação de Entrada", "Seja Bem-Vindo!!")


    def caixa2():
        tk.messagebox.showinfo("Saudação de Saída", "Adeus e até à próxima!!")
    btn1 = tk.Button(root, text="Entrada",command=caixa1)
    btn1.pack(padx=10, pady=5)
    button1_ttp = CreateToolTip(btn1,'Olá a todos!')

    btn2 = tk.Button(root, text="Saída",command=caixa2)
    btn2.pack(padx=10, pady=5)
    button2_ttp = CreateToolTip(btn2,"Adeus a todos!!!!")
    root.mainloop()