Develop Reference

communication between tkinter toplevels

I'm working on a little project and made a little on-screen keyboard as a tkinter Toplevel
my application is buildt like this:
Root-Window (Tk-Widget)
input 1 (Entry-Widget)
input 2 (Entry-Widget)
input 3 (Text-Widget)
on_screen-keyboard (Toplevel-Widget)
the Toplevel-Widget contains Buttons, with callbacks that should enter text in the entries (just like keyboard-Buttons)
What I want is a communication between children of the keyboard/the keyboard and the last active input-Widget. My Problem is, that I don't know, how to say the keyboard, to which input-Widget it should send the message.
import tkinter as tk
from tkinter import ttk
class MainWindow(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.active_input = tk.Variable(value=None)
ttk.Button(self, text="show Keyboard", command=lambda: Keyboard(self)).pack()
self.text = tk.StringVar(value="")
self.input1 = ttk.Entry(self)
self.input1.bind("<FocusIn>", lambda e: self.active_input.set(self.input1))
self.input2 = ttk.Entry(self)
self.input2.bind("<FocusIn>", lambda e: self.active_input.set(self.input2))
self.input3 = tk.Text(self, height=3, width=15)
self.input3.bind("<FocusIn>", lambda e: self.active_input.set(self.input3))
self.input1.pack()
self.input3.pack()
self.input2.pack()
class Keyboard(tk.Toplevel):
OPENED = False
NAME = "- Keyboard -"
NUM = [{"text":"1", "width":1},
{"text":"2", "width":1},
{"text":"3", "width":2}]
CHAR= [{"text":"A", "width":1},
{"text":"B", "width":1},
{"text":"C", "width":2}]
def __init__(self, master):
if not Keyboard.OPENED:
Keyboard.OPENED = True
print("keyboard opened!")
self.master = master
tk.Toplevel.__init__(self, master)
self.title(self.NAME)
self.protocol("WM_DELETE_WINDOW", self.close)
self.keyb_nb = ttk.Notebook(self)
self.keyb_nb.pack()
self.num_tab = ttk.Frame(self.keyb_nb)
self.createPad(self.num_tab, Keyboard.NUM,2)
self.keyb_nb.add(self.num_tab, text="123")
self.char_tab = ttk.Frame(self.keyb_nb)
self.createPad(self.char_tab, Keyboard.CHAR, 2)
self.keyb_nb.add(self.char_tab, text="ABC")
def createPad(self, master, pad:list, max_col):
self.co_count = 0
self.ro = 1
for button in pad:
button["id"] = ttk.Button(master, width=6*button["width"], text=button["text"], command=self.bclicked(button))
if self.co_count >= max_col:
self.ro = self.ro + 1
self.co_count = 0
button["id"].grid(row=self.ro, columnspan=button["width"], column=self.co_count)
self.co_count = self.co_count+button["width"]
def bclicked(self, button:dict):
"""
reciver = self.master.active_input #I think the Problem here is, that the variable contains a string, not a widget
reciever.focus_force()
reciever.insert(index=tk.INSERT, string=button["text"])
"""
pass
def close(self):
Keyboard.OPENED = False
self.destroy()
print("keyboard closed!")
root = MainWindow()
root.mainloop()
Here the init of the Mainwindow and the bclicked of the Keyboard class are important...
the code is debug-ready
I would prefer a solution, similar to the communication in the internet (sender=button, receiver-id, message), but very welcome every working solution
btw: I'm also looking for a solution, how I don't have to force the input to focus and the Toplevel stays an the highest layer of the screen (that if I focus the Tk-Widget/one of the inputs/the button, the keyboard will stay in front of it)
SUMMARY: how do I find out, which of the 3 input-widgets was active at last, when the keyboard-toplevel has already the focus?

I may made more changes than needed, but mainly focus on the method keyboard_triger() and pass_key_to_master(), this two use the idea that the variable master implements, having access to call methods out of scope.
Olso the method set_focused_object() stores a reference to the last object beeng focused, note than it stores the widget and not the event, it's easyer than searching each time the object
import tkinter as tk
from tkinter import ttk
class MainWindow(tk.Tk):
def keyboard_triger(self, key):
# to identify wath object is just use
# isinstance(self.active_input, ttk.Entry)
self.active_input.insert(tk.END, key)
def new_keyboard(self):
Keyboard(self)
def set_focused_object(self, event):
self.active_input = event.widget
def __init__(self):
tk.Tk.__init__(self)
self.active_input = None
ttk.Button(self, text="Show Keyboard", command=self.new_keyboard).pack()
self.input1 = ttk.Entry(self)
self.input1.bind("<FocusIn>", self.set_focused_object)
self.input1.pack()
self.input2 = ttk.Entry(self)
self.input2.bind("<FocusIn>", self.set_focused_object)
self.input2.pack()
self.input3 = tk.Text(self, height=3, width=15)
self.input3.bind("<FocusIn>", self.set_focused_object)
self.input3.pack()
class Keyboard(tk.Toplevel):
def pass_key_to_master(self, key):
self.master.keyboard_triger(key)
def __init__(self, master):
tk.Toplevel.__init__(self, master)
self.master = master
self.title('Keyboard')
# this way of agruping keys stores the kwags
# of the drawing method
keys = {
'A': {'x': 0, 'y': 0},
'B': {'x': 20, 'y': 20},
'C': {'x': 50, 'y': 50}
}
# expected structure
# {string key: reference to the button}
self.buttons = {}
for i in keys:
self.buttons[i] = tk.Button( # i=i is required to make a instance
self, text=i, command=lambda i=i: self.pass_key_to_master(i)
)
self.buttons[i].place(**keys[i])
if __name__ == '__main__':
root = MainWindow()
root.mainloop()

Your code maybe could have a better construction.(But I didn't revise your code construction.)
Followed by your code,I use a global variable.And fix some errors in your code.And it could work normally in my computer.
import tkinter as tk
from tkinter import ttk
class MainWindow(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.active_input = tk.Variable(value=None)
ttk.Button(self, text="show Keyboard", command=lambda: Keyboard(self)).pack()
global focusedWidget
focusedWidget = None
self.text = tk.StringVar(value="")
self.input1 = ttk.Entry(self)
self.input1.bind("<FocusIn>", self.getFocusWidget)
self.input2 = ttk.Entry(self)
self.input2.bind("<FocusIn>", self.getFocusWidget)
self.input3 = tk.Text(self, height=3, width=15)
self.input3.bind("<FocusIn>", self.getFocusWidget)
self.input1.pack()
self.input3.pack()
self.input2.pack()
def getFocusWidget(self,event): # this function could be a static function
global focusedWidget
focusedWidget = event.widget
class Keyboard(tk.Toplevel):
OPENED = False
NAME = "- Keyboard -"
NUM = [{"text":"1", "width":1},
{"text":"2", "width":1},
{"text":"3", "width":2}]
CHAR= [{"text":"A", "width":1},
{"text":"B", "width":1},
{"text":"C", "width":2}]
def __init__(self, master):
if not Keyboard.OPENED:
Keyboard.OPENED = True
print("keyboard opened!")
self.master = master
tk.Toplevel.__init__(self, master)
self.title(self.NAME)
self.protocol("WM_DELETE_WINDOW", self.close)
self.keyb_nb = ttk.Notebook(self)
self.keyb_nb.pack()
self.num_tab = ttk.Frame(self.keyb_nb)
self.createPad(self.num_tab, Keyboard.NUM,2)
self.keyb_nb.add(self.num_tab, text="123")
self.char_tab = ttk.Frame(self.keyb_nb)
self.createPad(self.char_tab, Keyboard.CHAR, 2)
self.keyb_nb.add(self.char_tab, text="ABC")
def createPad(self, master, pad:list, max_col):
self.co_count = 0
self.ro = 1
for button in pad:
button["id"] = ttk.Button(master, width=6*button["width"], text=button["text"], command=lambda button=button:self.bclicked(button)) # this lambda expression has some errors.
if self.co_count >= max_col:
self.ro = self.ro + 1
self.co_count = 0
button["id"].grid(row=self.ro, columnspan=button["width"], column=self.co_count)
self.co_count = self.co_count+button["width"]
def bclicked(self, button:dict):
global focusedWidget
"""
reciver = self.master.active_input #I think the Problem here is, that the variable contains a string, not a widget
reciever.focus_force()
reciever.insert(index=tk.INSERT, string=button["text"])
"""
if not focusedWidget: # If user hasn't click a entry or text widget.
print("Please select a entry or text")
return
if focusedWidget.widgetName=='ttk::entry': # use if statement to check the type of selected entry.
focusedWidget.insert(index=tk.INSERT,string=button["text"])
else:
focusedWidget.insert("end",button["text"])
def close(self):
Keyboard.OPENED = False
self.destroy()
print("keyboard closed!")
root = MainWindow()
root.mainloop()

Tkinter event binding of entry widget for password verification

I am trying to use a entry widget for password input, a handler function for password verification and a label widget for displaying the result of the verification. The code is as following so far,
class LoginFrame(Frame):
def __init__(self, parent):
#Frame.__init__(self, parent)
super(LoginFrame, self).__init__()
self.parent = parent
self.initUI()
# initialize the login screen UI
def initUI(self):
# Set up login frame properties
self.parent.title("Login Screen")
# creating instruction label
inst_lbl = self.make_label(self.parent, "Please login to continue")
# creating labels and entries for user name and password
user_name = self.make_entry(self.parent, caption="User Name:")
pwd = self.make_entry(self.parent, caption="User Password:", show="*")
# create a login button
login_btn = self.make_button(self.parent, self.verify_user, "Login")
# create a button
#----------------------------------------------------------------------
def make_button(self, parent, command, caption=NONE, side=TOP, width=0, **options):
"""make a button"""
btn = Button(parent, text=caption, command=command)
if side is not TOP:
btn.pack(side=side)
else:
btn.pack()
return btn
def make_label(self, parent, caption=NONE, side=TOP, **options):
label = Label(parent, text=caption, **options)
if side is not TOP:
label.pack(side=side)
else:
label.pack()
return label
def make_entry(self, parent, caption=NONE, side=TOP, width=0, **options):
#Label(parent, text=caption).pack(side=LEFT)
self.make_label(self.parent, caption, side)
entry = Entry(parent, **options)
if width:
entry.config(width=width)
if side is not TOP:
entry.pack(side=side)
else:
entry.pack()
return entry
# verify user name and password
#----------------------------------------------------------------------
def verify_user(event):
"""verify users"""
if user_name.get() == "admin" and pwd.get() == "123":
#inst_lbl.configure(text="User verified")
event.widget.config(text="User verified")
else:
#inst_lbl.configure(text="Access denied. Invalid username or password")
event.widget.config(text="Access denied. Invalid username or password")
def main():
top = Tk()
app = LoginFrame(top)
top.mainloop()
if __name__ == '__main__':
main()
now, I need user_name and pwd to be verified by the method verify_user, the result is shown in inst_lbl whenever the button login_btn is clicked (to trigger the verification). So how to bind inst_lbl to verify_user, in response to the login_btn click event? and how to get the contents of user_name and pwd to get verified in verify_user?

Make them class variable by adding self. prefixes. This way you can access them outside of the method they are created.
self.inst_lbl = self.make_label(...)
self.user_name = self.make_entry(...)
self.pwd = self.make_entry(...)
When trying to call them, you also will need self. prefixes.
self.inst_lbl.configure(...)
Other than that, you'll be needing self parameter in verify_user method since it's a member of a class.
Also, for Python-2.x, you'll get TypeError: must be type, not classobj on your super(LoginFrame, self).__init__(). The line you commented out is the right one to use.
Frame.__init__(self, parent)
If you want to use super(), you should add object as parameter to your class definiton because of old style classes etc.
class LoginFrame(Frame, object):

_tkinter.TclError: bad side: must be top, bottom, left, or right

I defined a method for creating a label with the following code,
from tkinter import *
class LoginFrame(Frame):
def __init__(self, parent):
super(LoginFrame, self).__init__()
self.parent = parent
self.initUI()
# initialize the login screen UI
def initUI(self):
self.parent.title("Login Screen")
# Set up login frame properties
self.parent.title("Login Screen")
# create a background image
photo_bg = PhotoImage(file="building.gif")
building = self.make_label(self.parent, image=photo_bg)
# creating instruction label, where the error occurs
inst_lbl = self.make_label(self.parent, "Please login to continue")
def make_label(parent, caption=NONE, side=TOP, **options):
label = Label(parent, text=caption, **options)
if side is not TOP:
label.pack(side=side)
else:
label.pack()
return label
def main():
top = Tk()
app = LoginFrame(top)
top.mainloop()
if __name__ == '__main__':
main()
I got an error when tried to run the code,
_tkinter.TclError: bad side "Please login to continue": must be top, bottom, left, or right
I am wondering how to resolve the issue? There was no error when creating the back ground image using make_label.

Your definition of make_label is missing the self parameter. You need to define it as this:
def make_label(self, parent, ...):

Python Tkinter, how to disable a button in a class?

I have seen many explanations of how to turn an enabled button disabled but not when classes are involved. The error here is in the line 'button_1.config...' and the error message is that button_1 is not defined. I think this is because it is in a different method but im not sure how to disable a button from a different method. any help is appreciated.
from tkinter import *
class menu:
def __init__(self, master):
self.master = master
button_1 = Button(self.master, text = 'test', command = self.correct).pack()
def correct(self):
button_1.config(state = DISABLED)
def window():
root = Tk()
menu(root)
root.mainloop()
if __name__ == '__main__':
window()

The button needs to be an instance variable, if you're accessing it between methods in the class. Just add self. in front of it. It's also going to need to be packed on a separate line, otherwise the instance variable self.button_1 will return None:
class menu:
def __init__(self, master):
self.master = master
self.button_1 = Button(self.master, text = 'test', command = self.correct)
self.button_1.pack()
def correct(self):
self.button_1.config(state = DISABLED)

tkinter app adding a right click context menu?

I have a python-tkinter gui app that I've been trying to find some way to add in some functionality. I was hoping there would be a way to right-click on an item in the app's listbox area and bring up a context menu. Is tkinter able to accomplish this? Would I be better off looking into gtk or some other gui-toolkit?

You would create a Menu instance and write a function that calls
its post() or tk_popup() method.
The tkinter documentation doesn't currently have any information about tk_popup().
Read the Tk documentation for a description, or the source:
library/menu.tcl in the Tcl/Tk source:
::tk_popup --
This procedure pops up a menu and sets things up for traversing
the menu and its submenus.
Arguments:
menu - Name of the menu to be popped up.
x, y - Root coordinates at which to pop up the menu.
entry - Index of a menu entry to center over (x,y).
If omitted or specified as {}, then menu's
upper-left corner goes at (x,y).
tkinter/__init__.py in the Python source:
def tk_popup(self, x, y, entry=""):
"""Post the menu at position X,Y with entry ENTRY."""
self.tk.call('tk_popup', self._w, x, y, entry)
You associate your context menu invoking function with right-click via:
the_widget_clicked_on.bind("<Button-3>", your_function).
However, the number associated with right-click is not the same on every platform.
library/tk.tcl in the Tcl/Tk source:
On Darwin/Aqua, buttons from left to right are 1,3,2.
On Darwin/X11 with recent XQuartz as the X server, they are 1,2,3;
other X servers may differ.
Here is an example I wrote that adds a context menu to a Listbox:
import tkinter # Tkinter -> tkinter in Python 3
class FancyListbox(tkinter.Listbox):
def __init__(self, parent, *args, **kwargs):
tkinter.Listbox.__init__(self, parent, *args, **kwargs)
self.popup_menu = tkinter.Menu(self, tearoff=0)
self.popup_menu.add_command(label="Delete",
command=self.delete_selected)
self.popup_menu.add_command(label="Select All",
command=self.select_all)
self.bind("<Button-3>", self.popup) # Button-2 on Aqua
def popup(self, event):
try:
self.popup_menu.tk_popup(event.x_root, event.y_root, 0)
finally:
self.popup_menu.grab_release()
def delete_selected(self):
for i in self.curselection()[::-1]:
self.delete(i)
def select_all(self):
self.selection_set(0, 'end')
root = tkinter.Tk()
flb = FancyListbox(root, selectmode='multiple')
for n in range(10):
flb.insert('end', n)
flb.pack()
root.mainloop()
The use of grab_release() was observed in an example on effbot.
Its effect might not be the same on all systems.

I made some changes to the conext menu code above in order to adjust my demand and I think it would be useful to share:
Version 1:
import tkinter as tk
from tkinter import ttk
class Main(tk.Frame):
def __init__(self, master):
tk.Frame.__init__(self, master)
master.geometry('500x350')
self.master = master
self.tree = ttk.Treeview(self.master, height=15)
self.tree.pack(fill='x')
self.btn = tk.Button(master, text='click', command=self.clickbtn)
self.btn.pack()
self.aMenu = tk.Menu(master, tearoff=0)
self.aMenu.add_command(label='Delete', command=self.delete)
self.aMenu.add_command(label='Say Hello', command=self.hello)
self.num = 0
# attach popup to treeview widget
self.tree.bind("<Button-3>", self.popup)
def clickbtn(self):
text = 'Hello ' + str(self.num)
self.tree.insert('', 'end', text=text)
self.num += 1
def delete(self):
print(self.tree.focus())
if self.iid:
self.tree.delete(self.iid)
def hello(self):
print ('hello!')
def popup(self, event):
self.iid = self.tree.identify_row(event.y)
if self.iid:
# mouse pointer over item
self.tree.selection_set(self.iid)
self.aMenu.post(event.x_root, event.y_root)
else:
pass
root = tk.Tk()
app=Main(root)
root.mainloop()
Version 2:
import tkinter as tk
from tkinter import ttk
class Main(tk.Frame):
def __init__(self, master):
master.geometry('500x350')
self.master = master
tk.Frame.__init__(self, master)
self.tree = ttk.Treeview(self.master, height=15)
self.tree.pack(fill='x')
self.btn = tk.Button(master, text='click', command=self.clickbtn)
self.btn.pack()
self.rclick = RightClick(self.master)
self.num = 0
# attach popup to treeview widget
self.tree.bind('<Button-3>', self.rclick.popup)
def clickbtn(self):
text = 'Hello ' + str(self.num)
self.tree.insert('', 'end', text=text)
self.num += 1
class RightClick:
def __init__(self, master):
# create a popup menu
self.aMenu = tk.Menu(master, tearoff=0)
self.aMenu.add_command(label='Delete', command=self.delete)
self.aMenu.add_command(label='Say Hello', command=self.hello)
self.tree_item = ''
def delete(self):
if self.tree_item:
app.tree.delete(self.tree_item)
def hello(self):
print ('hello!')
def popup(self, event):
self.aMenu.post(event.x_root, event.y_root)
self.tree_item = app.tree.focus()
root = tk.Tk()
app=Main(root)
root.mainloop()

from tkinter import *
root=Tk()
root.geometry("500x400+200+100")
class Menu_Entry(Entry):
def __init__(self,perant,*args,**kwargs):
Entry.__init__(self,perant,*args,**kwargs)
self.popup_menu=Menu(self,tearoff=0,background='#1c1b1a',fg='white',
activebackground='#534c5c',
activeforeground='Yellow')
self.popup_menu.add_command(label="Cut ",command=self.Cut,
accelerator='Ctrl+V')
self.popup_menu.add_command(label="Copy ",command=self.Copy,compound=LEFT,
accelerator='Ctrl+C')
self.popup_menu.add_command(label="Paste ",command=self.Paste,accelerator='Ctrl+V')
self.popup_menu.add_separator()
self.popup_menu.add_command(label="Select all",command=self.select_all,accelerator="Ctrl+A")
self.popup_menu.add_command(label="Delete",command=self.delete_only,accelerator=" Delete")
self.popup_menu.add_command(label="Delete all",command=self.delete_selected,accelerator="Ctrl+D")
self.bind('<Button-3>',self.popup)
self.bind("<Control-d>",self.delete_selected_with_e1)
self.bind('<App>',self.popup)
self.context_menu = Menu(self, tearoff=0)
self.context_menu.add_command(label="Cut")
self.context_menu.add_command(label="Copy")
self.context_menu.add_command(label="Paste")
def popup(self, event):
try:
self.popup_menu.tk_popup(event.x_root, event.y_root, 0)
finally:
self.popup_menu.grab_release()
def Copy(self):
self.event_generate('<<Copy>>')
def Paste(self):
self.event_generate('<<Paste>>')
def Cut(self):
self.event_generate('<<Cut>>')
def delete_selected_with_e1(self,event):
self.select_range(0, END)
self.focus()
self.event_generate("<Delete>")
def delete_selected(self):
self.select_range(0, END)
self.focus()
self.event_generate("<Delete>")
def delete_only(self):
self.event_generate("<BackSpace>")
def select_all(self):
self.select_range(0, END)
self.focus()
ent=Menu_Entry(root)
ent.pack()
root.mainloop()

Important Caveat:
(Assuming the event argument that contains the coordinates is called "event"): Nothing will happen or be visible when you call tk_popup(...) unless you use "event.x_root" and "event.y_root" as arguments. If you do the obvious of using "event.x" and "event.y", it won't work, even though the names of the coordinates are "x" and "y" and there is no mention of "x_root" and "y_root" anywhere within it.
As for the grab_release(..), it's not necessary, anywhere. "tearoff=0" also isn't necessary, setting it to 1 (which is default), simply adds a dotted line entry to the context menu. If you click on it, it detaches the context menu and makes it its own top-level window with window decorators. tearoff=0 will hide this entry. Moreover, it doesn't matter if you set the menu's master to any specific widget or root, or anything at all.