Display message when hovering over something with mouse cursor in Python

Question

I have a GUI made with TKinter in Python. I would like to be able to display a message when my mouse cursor goes, for example, on top of a label or button. The purpose of th

Answer 1

The best way I have found to create a popup help window is to use the tix.Balloon. I have modified it below to make it look better and show an example (note the use of tix.Tk):

import tkinter as tk
import tkinter.tix as tix


class Balloon(tix.Balloon):

    # A modified tix popup balloon (to change the default delay, bg and wraplength)

    init_after = 1250  # Milliseconds
    wraplength = 300  # Pixels

    def __init__(self, master):
        bg = root.cget("bg")
        # Call the parent
        super().__init__(master, initwait=self.init_after)
        # Change background colour
        for i in self.subwidgets_all():
            i.config(bg=bg)
        # Modify the balloon label
        self.message.config(wraplength=self.wraplength)


root = tix.Tk()

l = tk.Label(root, text="\n".join(["text"] * 5))
l.pack()

b = Balloon(root.winfo_toplevel())
b.bind_widget(l, balloonmsg="Some random text")

root.mainloop()

OLD ANSWER:

Here is an example using and as @bryanoakley suggested with a toplevel (with overridedirect set to true). Use the hover_timer class for easy use of this. This needs the widget and help-text (with an optional delay argument - default 0.5s) and can be easily called just by initiating the class and then cancelling it.

import threading, time
from tkinter import *

class hover_window (Toplevel):

    def __init__ (self, coords, text):
        super ().__init__ ()
        self.geometry ("+%d+%d" % (coords [0], coords [1]))
        self.config (bg = "white")
        Label (self, text = text, bg = "white", relief = "ridge", borderwidth = 3, wraplength = 400, justify = "left").grid ()
        self.overrideredirect (True)
        self.update ()
        self.bind ("", lambda event: self.destroy ())

class hover_timer:

    def __init__ (self, widget, text, delay = 2):
        self.wind, self.cancel_var, self.widget, self.text, self.active, self.delay = None, False, widget, text, False, delay
        threading.Thread (target = self.start_timer).start ()

    def start_timer (self):
        self.active = True
        time.sleep (self.delay)
        if not self.cancel_var: self.wind = hover_window ((self.widget.winfo_rootx (), self.widget.winfo_rooty () + self.widget.winfo_height () + 20), self.text)
        self.active = False

    def delayed_stop (self):
        while self.active: time.sleep (0.05)
        if self.wind:
            self.wind.destroy ()
            self.wind = None

    def cancel (self):
        self.cancel_var = True
        if not self.wind: threading.Thread (target = self.delayed_stop).start ()
        else:
            self.wind.destroy ()
            self.wind = None

def start_help (event):
    # Create a new help timer
    global h
    h = hover_timer (l, "This is some additional information.", 0.5)

def end_help (event):
    # If therre is one, end the help timer
    if h: h.cancel ()

if __name__ == "__main__":

    # Create the tkinter window
    root = Tk ()
    root.title ("Hover example")

    # Help class not created yet
    h = None

    # Padding round label
    Frame (root, width = 50).grid (row = 1, column = 0)
    Frame (root, height = 50).grid (row = 0, column = 1)
    Frame (root, width = 50).grid (row = 1, column = 2)
    Frame (root, height = 50).grid (row = 2, column = 1)

    # Setup the label
    l = Label (root, text = "Hover over me for information.", font = ("sans", 32))
    l.grid (row = 1, column = 1)
    l.bind ("", start_help)
    l.bind ("", end_help)

    # Tkinter mainloop
    root.mainloop ()