Related
Suppose I have the following Button made with Tkinter in Python:
import Tkinter as Tk
win = Tk.Toplevel()
frame = Tk.Frame(master=win).grid(row=1, column=1)
button = Tk.Button(master=frame, text='press', command=action)
The method action is called when I press the button, but what if I wanted to pass some arguments to the method action?
I have tried with the following code:
button = Tk.Button(master=frame, text='press', command=action(someNumber))
This just invokes the method immediately, and pressing the button does nothing.
See Python Argument Binders for standard techniques (not Tkinter-specific) for solving the problem. Working with callbacks in Tkinter (or other GUI frameworks) has some special considerations because the return value from the callback is useless.
If you try to create multiple Buttons in a loop, passing each one different arguments based on the loop counter, you may run into problems due to what is called late binding. Please see tkinter creating buttons in for loop passing command arguments for details.
I personally prefer to use lambdas in such a scenario, because imo it's clearer and simpler and also doesn't force you to write lots of wrapper methods if you don't have control over the called method, but that's certainly a matter of taste.
That's how you'd do it with a lambda (note there's also some implementation of currying in the functional module, so you can use that too):
button = Tk.Button(master=frame, text='press', command= lambda: action(someNumber))
This can also be done by using partial from the standard library functools, like this:
from functools import partial
#(...)
action_with_arg = partial(action, arg)
button = Tk.Button(master=frame, text='press', command=action_with_arg)
Example GUI:
Let's say I have the GUI:
import tkinter as tk
root = tk.Tk()
btn = tk.Button(root, text="Press")
btn.pack()
root.mainloop()
What Happens When a Button Is Pressed
See that when btn is pressed it calls its own function which is very similar to button_press_handle in the following example:
def button_press_handle(callback=None):
if callback:
callback() # Where exactly the method assigned to btn['command'] is being callled
with:
button_press_handle(btn['command'])
You can simply think that command option should be set as, the reference to the method we want to be called, similar to callback in button_press_handle.
Calling a Method(Callback) When the Button is Pressed
Without arguments
So if I wanted to print something when the button is pressed I would need to set:
btn['command'] = print # default to print is new line
Pay close attention to the lack of () with the print method which is omitted in the meaning that: "This is the method's name which I want you to call when pressed but don't call it just this very instant." However, I didn't pass any arguments for the print so it printed whatever it prints when called without arguments.
With Argument(s)
Now If I wanted to also pass arguments to the method I want to be called when the button is pressed I could make use of the anonymous functions, which can be created with lambda statement, in this case for print built-in method, like the following:
btn['command'] = lambda arg1="Hello", arg2=" ", arg3="World!" : print(arg1 + arg2 + arg3)
Calling Multiple Methods when the Button Is Pressed
Without Arguments
You can also achieve that using lambda statement but it is considered bad practice and thus I won't include it here. The good practice is to define a separate method, multiple_methods, that calls the methods wanted and then set it as the callback to the button press:
def multiple_methods():
print("Vicariously") # the first inner callback
print("I") # another inner callback
With Argument(s)
In order to pass argument(s) to method that calls other methods, again make use of lambda statement, but first:
def multiple_methods(*args, **kwargs):
print(args[0]) # the first inner callback
print(kwargs['opt1']) # another inner callback
and then set:
btn['command'] = lambda arg="live", kw="as the" : a_new_method(arg, opt1=kw)
Returning Object(s) From the Callback
Also further note that callback can't really return because it's only called inside button_press_handle with callback() as opposed to return callback(). It does return but not anywhere outside that function. Thus you should rather modify object(s) that are accessible in the current scope.
Complete Example with global Object Modification(s)
Below example will call a method that changes btn's text each time the button is pressed:
import tkinter as tk
i = 0
def text_mod():
global i, btn # btn can be omitted but not sure if should be
txt = ("Vicariously", "I", "live", "as", "the", "whole", "world", "dies")
btn['text'] = txt[i] # the global object that is modified
i = (i + 1) % len(txt) # another global object that gets modified
root = tk.Tk()
btn = tk.Button(root, text="My Button")
btn['command'] = text_mod
btn.pack(fill='both', expand=True)
root.mainloop()
Mirror
Just to make the answer of Nae a little bit more elaborate, here is a full blown example which includes the possibility to pass a variable to the callback which contains different values for each button:
import tkinter as tk
def callback(text):
print(text)
top = tk.Tk()
Texts=["text1", "text2", "text3"]
Buttons=[]
for i, z in enumerate(Texts):
Buttons.append(tk.Button(top, text=z, command= lambda ztemp=z : callback(ztemp)))
Buttons[i].pack(side=tk.LEFT, padx=5)
top.mainloop()
By defining a temporary variable ztemp, the value of that variable gets fixed at the moment when the button is defined.
Python's ability to provide default values for function arguments gives us a way out.
def fce(x=myX, y=myY):
myFunction(x,y)
button = Tk.Button(mainWin, text='press', command=fce)
See: https://tkdocs.com/shipman/extra-args.html
For more buttons you can create a function which returns a function:
def fce(myX, myY):
def wrapper(x=myX, y=myY):
pass
pass
pass
return x+y
return wrapper
button1 = Tk.Button(mainWin, text='press 1', command=fce(1,2))
button2 = Tk.Button(mainWin, text='press 2', command=fce(3,4))
button3 = Tk.Button(mainWin, text='press 3', command=fce(9,8))
Building on Matt Thompsons answer : a class can be made callable so it can be used instead of a function:
import tkinter as tk
class Callback:
def __init__(self, func, *args, **kwargs):
self.func = func
self.args = args
self.kwargs = kwargs
def __call__(self):
self.func(*self.args, **self.kwargs)
def default_callback(t):
print("Button '{}' pressed.".format(t))
root = tk.Tk()
buttons = ["A", "B", "C"]
for i, b in enumerate(buttons):
tk.Button(root, text=b, command=Callback(default_callback, b)).grid(row=i, column=0)
tk.mainloop()
Use lambda
import tkinter as tk
root = tk.Tk()
def go(text):
print(text)
b = tk.Button(root, text="Click", command=lambda: go("hello"))
b.pack()
root.mainloop()
output:
hello
One simple way would be to configure button with lambda like the following syntax:
button['command'] = lambda arg1 = local_var1, arg2 = local_var2 : function(arg1, arg2)
button = Tk.Button(master=frame, text='press', command=lambda: action(someNumber))
I believe should fix this
The reason it invokes the method immediately and pressing the button does nothing is that action(somenumber) is evaluated and its return value is attributed as the command for the button. So if action prints something to tell you it has run and returns None, you just run action to evaluate its return value and given None as the command for the button.
To have buttons to call functions with different arguments you can use global variables, although I can't recommend it:
import Tkinter as Tk
frame = Tk.Frame(width=5, height=2, bd=1, relief=Tk.SUNKEN)
frame.grid(row=2,column=2)
frame.pack(fill=Tk.X, padx=5, pady=5)
def action():
global output
global variable
output.insert(Tk.END,variable.get())
button = Tk.Button(master=frame, text='press', command=action)
button.pack()
variable = Tk.Entry(master=frame)
variable.pack()
output = Tk.Text(master=frame)
output.pack()
if __name__ == '__main__':
Tk.mainloop()
What I would do is make a class whose objects would contain every variable required and methods to change those as needed:
import Tkinter as Tk
class Window:
def __init__(self):
self.frame = Tk.Frame(width=5, height=2, bd=1, relief=Tk.SUNKEN)
self.frame.grid(row=2,column=2)
self.frame.pack(fill=Tk.X, padx=5, pady=5)
self.button = Tk.Button(master=self.frame, text='press', command=self.action)
self.button.pack()
self.variable = Tk.Entry(master=self.frame)
self.variable.pack()
self.output = Tk.Text(master=self.frame)
self.output.pack()
def action(self):
self.output.insert(Tk.END,self.variable.get())
if __name__ == '__main__':
window = Window()
Tk.mainloop()
The best thing to do is use lambda as follows:
button = Tk.Button(master=frame, text='press', command=lambda: action(someNumber))
I am extremely late, but here is a very simple way of accomplishing it.
import tkinter as tk
def function1(param1, param2):
print(str(param1) + str(param2))
var1 = "Hello "
var2 = "World!"
def function2():
function1(var1, var2)
root = tk.Tk()
myButton = tk.Button(root, text="Button", command=function2)
root.mainloop()
You simply wrap the function you want to use in another function and call the second function on the button press.
Lambdas are all well and good, but you can also try this (which works in a for loop btw):
root = Tk()
dct = {"1": [*args], "2": [*args]}
def keypress(event):
*args = dct[event.char]
for arg in args:
pass
for i in range(10):
root.bind(str(i), keypress)
This works because when the binding is set, a key press passes the event as an argument. You can then call attributes off the event like event.char to get "1" or "UP" ect. If you need an argument or multiple arguments other than the event attributes. just create a dictionary to store them.
I have encountered this problem before, too.
You can just use lambda:
button = Tk.Button(master=frame, text='press',command=lambda: action(someNumber))
Use a lambda to pass the entry data to the command function if you have more actions to carry out, like this (I've tried to make it generic, so just adapt):
event1 = Entry(master)
button1 = Button(master, text="OK", command=lambda: test_event(event1.get()))
def test_event(event_text):
if not event_text:
print("Nothing entered")
else:
print(str(event_text))
# do stuff
This will pass the information in the event to the button function. There may be more Pythonesque ways of writing this, but it works for me.
JasonPy - a few things...
if you stick a button in a loop it will be created over and over and over again... which is probably not what you want. (maybe it is)...
The reason it always gets the last index is lambda events run when you click them - not when the program starts. I'm not sure 100% what you are doing but maybe try storing the value when it's made then call it later with the lambda button.
eg: (don't use this code, just an example)
for entry in stuff_that_is_happening:
value_store[entry] = stuff_that_is_happening
then you can say....
button... command: lambda: value_store[1]
hope this helps!
For posterity: you can also use classes to achieve something similar. For instance:
class Function_Wrapper():
def __init__(self, x, y, z):
self.x, self.y, self.z = x, y, z
def func(self):
return self.x + self.y + self.z # execute function
Button can then be simply created by:
instance1 = Function_Wrapper(x, y, z)
button1 = Button(master, text = "press", command = instance1.func)
This approach also allows you to change the function arguments by i.e. setting instance1.x = 3.
You need to use lambda:
button = Tk.Button(master=frame, text='press', command=lambda: action(someNumber))
I want to get the value in the event hander function.
If clicks prints in event hander function, then it will show 1, 2, 3, 4... by every click.
import tkinter as tk
root = tk.Tk()
clicks = 0
def click(event):
global clicks
clicks += 1
print(clicks)
button = tk.Button(root, text="click me!")
button.pack()
button.bind("<Button-1>", click)
root.mainloop()
If I print it in global, it will show 0 forever. But I want it prints 1, 2, 3 by every click not always 0.
def click(event):
global clicks
clicks += 1
return clicks
print(clicks)
This case is simplified. Actually, my real case is that there are many different items(like listbox, button1, button2...) event hander function(def xxx(event)), and I need to get some value in each function after trigger their events. Then do some conditional expressions in global.
I knew the methods like class, global variable, init, (self, master),
I think global variable is the simplest method but I really don't know how to return it in event hander function and use it in global.
Thanks for Help !!!
The reason why it always prints 0 is that the program resets everything every after you close the tk window. If you want to save the values even after you close the window, maybe save it in the csv file or put it in the database. Does this help? or am I too far from what you're trying to say?
Your first set of code should work with the global variable like what TheLizzard said. Like what Matiiss said, if you place the print outside the function, it would be called once and never be called again.
As for what you are looking for, I'm assuming you want the button to be like a next button going through each item from the listbox and each time the next button hit one of the item in the listbox, it calls another function to obtain whatever that item has. Hopefully this code is what you are looking for or give you an idea.
import tkinter as tk
root = tk.Tk()
lst = {'a':'a value', 'b':'b value', 'c':'c value'}
clicks = -1
def print_text(event):
keys = list(lst.keys())
print(lst[keys[lstbx.curselection()[0]]])
def click():
global clicks
lstbx.selection_clear(0, 'end')
clicks = clicks + 1 if clicks < 2 else 0 # loop the list when reach end
lstbx.selection_set(clicks)
lstbx.event_generate('<<ListboxSelect>>') # force call function
btn = tk.Button(root, text='Next', command=click)
btn.pack()
lstbx = tk.Listbox(root, selectmode='single')
lstbx.insert(0, *lst.keys())
lstbx.pack()
lstbx.bind('<<ListboxSelect>>', print_text)
root.mainloop()
Suppose I have the following Button made with Tkinter in Python:
import Tkinter as Tk
win = Tk.Toplevel()
frame = Tk.Frame(master=win).grid(row=1, column=1)
button = Tk.Button(master=frame, text='press', command=action)
The method action is called when I press the button, but what if I wanted to pass some arguments to the method action?
I have tried with the following code:
button = Tk.Button(master=frame, text='press', command=action(someNumber))
This just invokes the method immediately, and pressing the button does nothing.
See Python Argument Binders for standard techniques (not Tkinter-specific) for solving the problem. Working with callbacks in Tkinter (or other GUI frameworks) has some special considerations because the return value from the callback is useless.
If you try to create multiple Buttons in a loop, passing each one different arguments based on the loop counter, you may run into problems due to what is called late binding. Please see tkinter creating buttons in for loop passing command arguments for details.
I personally prefer to use lambdas in such a scenario, because imo it's clearer and simpler and also doesn't force you to write lots of wrapper methods if you don't have control over the called method, but that's certainly a matter of taste.
That's how you'd do it with a lambda (note there's also some implementation of currying in the functional module, so you can use that too):
button = Tk.Button(master=frame, text='press', command= lambda: action(someNumber))
This can also be done by using partial from the standard library functools, like this:
from functools import partial
#(...)
action_with_arg = partial(action, arg)
button = Tk.Button(master=frame, text='press', command=action_with_arg)
Example GUI:
Let's say I have the GUI:
import tkinter as tk
root = tk.Tk()
btn = tk.Button(root, text="Press")
btn.pack()
root.mainloop()
What Happens When a Button Is Pressed
See that when btn is pressed it calls its own function which is very similar to button_press_handle in the following example:
def button_press_handle(callback=None):
if callback:
callback() # Where exactly the method assigned to btn['command'] is being callled
with:
button_press_handle(btn['command'])
You can simply think that command option should be set as, the reference to the method we want to be called, similar to callback in button_press_handle.
Calling a Method(Callback) When the Button is Pressed
Without arguments
So if I wanted to print something when the button is pressed I would need to set:
btn['command'] = print # default to print is new line
Pay close attention to the lack of () with the print method which is omitted in the meaning that: "This is the method's name which I want you to call when pressed but don't call it just this very instant." However, I didn't pass any arguments for the print so it printed whatever it prints when called without arguments.
With Argument(s)
Now If I wanted to also pass arguments to the method I want to be called when the button is pressed I could make use of the anonymous functions, which can be created with lambda statement, in this case for print built-in method, like the following:
btn['command'] = lambda arg1="Hello", arg2=" ", arg3="World!" : print(arg1 + arg2 + arg3)
Calling Multiple Methods when the Button Is Pressed
Without Arguments
You can also achieve that using lambda statement but it is considered bad practice and thus I won't include it here. The good practice is to define a separate method, multiple_methods, that calls the methods wanted and then set it as the callback to the button press:
def multiple_methods():
print("Vicariously") # the first inner callback
print("I") # another inner callback
With Argument(s)
In order to pass argument(s) to method that calls other methods, again make use of lambda statement, but first:
def multiple_methods(*args, **kwargs):
print(args[0]) # the first inner callback
print(kwargs['opt1']) # another inner callback
and then set:
btn['command'] = lambda arg="live", kw="as the" : a_new_method(arg, opt1=kw)
Returning Object(s) From the Callback
Also further note that callback can't really return because it's only called inside button_press_handle with callback() as opposed to return callback(). It does return but not anywhere outside that function. Thus you should rather modify object(s) that are accessible in the current scope.
Complete Example with global Object Modification(s)
Below example will call a method that changes btn's text each time the button is pressed:
import tkinter as tk
i = 0
def text_mod():
global i, btn # btn can be omitted but not sure if should be
txt = ("Vicariously", "I", "live", "as", "the", "whole", "world", "dies")
btn['text'] = txt[i] # the global object that is modified
i = (i + 1) % len(txt) # another global object that gets modified
root = tk.Tk()
btn = tk.Button(root, text="My Button")
btn['command'] = text_mod
btn.pack(fill='both', expand=True)
root.mainloop()
Mirror
Just to make the answer of Nae a little bit more elaborate, here is a full blown example which includes the possibility to pass a variable to the callback which contains different values for each button:
import tkinter as tk
def callback(text):
print(text)
top = tk.Tk()
Texts=["text1", "text2", "text3"]
Buttons=[]
for i, z in enumerate(Texts):
Buttons.append(tk.Button(top, text=z, command= lambda ztemp=z : callback(ztemp)))
Buttons[i].pack(side=tk.LEFT, padx=5)
top.mainloop()
By defining a temporary variable ztemp, the value of that variable gets fixed at the moment when the button is defined.
Python's ability to provide default values for function arguments gives us a way out.
def fce(x=myX, y=myY):
myFunction(x,y)
button = Tk.Button(mainWin, text='press', command=fce)
See: https://tkdocs.com/shipman/extra-args.html
For more buttons you can create a function which returns a function:
def fce(myX, myY):
def wrapper(x=myX, y=myY):
pass
pass
pass
return x+y
return wrapper
button1 = Tk.Button(mainWin, text='press 1', command=fce(1,2))
button2 = Tk.Button(mainWin, text='press 2', command=fce(3,4))
button3 = Tk.Button(mainWin, text='press 3', command=fce(9,8))
Building on Matt Thompsons answer : a class can be made callable so it can be used instead of a function:
import tkinter as tk
class Callback:
def __init__(self, func, *args, **kwargs):
self.func = func
self.args = args
self.kwargs = kwargs
def __call__(self):
self.func(*self.args, **self.kwargs)
def default_callback(t):
print("Button '{}' pressed.".format(t))
root = tk.Tk()
buttons = ["A", "B", "C"]
for i, b in enumerate(buttons):
tk.Button(root, text=b, command=Callback(default_callback, b)).grid(row=i, column=0)
tk.mainloop()
Use lambda
import tkinter as tk
root = tk.Tk()
def go(text):
print(text)
b = tk.Button(root, text="Click", command=lambda: go("hello"))
b.pack()
root.mainloop()
output:
hello
One simple way would be to configure button with lambda like the following syntax:
button['command'] = lambda arg1 = local_var1, arg2 = local_var2 : function(arg1, arg2)
button = Tk.Button(master=frame, text='press', command=lambda: action(someNumber))
I believe should fix this
The reason it invokes the method immediately and pressing the button does nothing is that action(somenumber) is evaluated and its return value is attributed as the command for the button. So if action prints something to tell you it has run and returns None, you just run action to evaluate its return value and given None as the command for the button.
To have buttons to call functions with different arguments you can use global variables, although I can't recommend it:
import Tkinter as Tk
frame = Tk.Frame(width=5, height=2, bd=1, relief=Tk.SUNKEN)
frame.grid(row=2,column=2)
frame.pack(fill=Tk.X, padx=5, pady=5)
def action():
global output
global variable
output.insert(Tk.END,variable.get())
button = Tk.Button(master=frame, text='press', command=action)
button.pack()
variable = Tk.Entry(master=frame)
variable.pack()
output = Tk.Text(master=frame)
output.pack()
if __name__ == '__main__':
Tk.mainloop()
What I would do is make a class whose objects would contain every variable required and methods to change those as needed:
import Tkinter as Tk
class Window:
def __init__(self):
self.frame = Tk.Frame(width=5, height=2, bd=1, relief=Tk.SUNKEN)
self.frame.grid(row=2,column=2)
self.frame.pack(fill=Tk.X, padx=5, pady=5)
self.button = Tk.Button(master=self.frame, text='press', command=self.action)
self.button.pack()
self.variable = Tk.Entry(master=self.frame)
self.variable.pack()
self.output = Tk.Text(master=self.frame)
self.output.pack()
def action(self):
self.output.insert(Tk.END,self.variable.get())
if __name__ == '__main__':
window = Window()
Tk.mainloop()
The best thing to do is use lambda as follows:
button = Tk.Button(master=frame, text='press', command=lambda: action(someNumber))
I am extremely late, but here is a very simple way of accomplishing it.
import tkinter as tk
def function1(param1, param2):
print(str(param1) + str(param2))
var1 = "Hello "
var2 = "World!"
def function2():
function1(var1, var2)
root = tk.Tk()
myButton = tk.Button(root, text="Button", command=function2)
root.mainloop()
You simply wrap the function you want to use in another function and call the second function on the button press.
Lambdas are all well and good, but you can also try this (which works in a for loop btw):
root = Tk()
dct = {"1": [*args], "2": [*args]}
def keypress(event):
*args = dct[event.char]
for arg in args:
pass
for i in range(10):
root.bind(str(i), keypress)
This works because when the binding is set, a key press passes the event as an argument. You can then call attributes off the event like event.char to get "1" or "UP" ect. If you need an argument or multiple arguments other than the event attributes. just create a dictionary to store them.
I have encountered this problem before, too.
You can just use lambda:
button = Tk.Button(master=frame, text='press',command=lambda: action(someNumber))
Use a lambda to pass the entry data to the command function if you have more actions to carry out, like this (I've tried to make it generic, so just adapt):
event1 = Entry(master)
button1 = Button(master, text="OK", command=lambda: test_event(event1.get()))
def test_event(event_text):
if not event_text:
print("Nothing entered")
else:
print(str(event_text))
# do stuff
This will pass the information in the event to the button function. There may be more Pythonesque ways of writing this, but it works for me.
JasonPy - a few things...
if you stick a button in a loop it will be created over and over and over again... which is probably not what you want. (maybe it is)...
The reason it always gets the last index is lambda events run when you click them - not when the program starts. I'm not sure 100% what you are doing but maybe try storing the value when it's made then call it later with the lambda button.
eg: (don't use this code, just an example)
for entry in stuff_that_is_happening:
value_store[entry] = stuff_that_is_happening
then you can say....
button... command: lambda: value_store[1]
hope this helps!
For posterity: you can also use classes to achieve something similar. For instance:
class Function_Wrapper():
def __init__(self, x, y, z):
self.x, self.y, self.z = x, y, z
def func(self):
return self.x + self.y + self.z # execute function
Button can then be simply created by:
instance1 = Function_Wrapper(x, y, z)
button1 = Button(master, text = "press", command = instance1.func)
This approach also allows you to change the function arguments by i.e. setting instance1.x = 3.
You need to use lambda:
button = Tk.Button(master=frame, text='press', command=lambda: action(someNumber))
I have this simple program that I wrote so I could better understand the 'return' function and how to pass a value from one function to another. All this program does is to pass the value of buttontwo=2 to the function button_one_function,so if button two is pressed first then button one does nothing.I thought that I could do this without using a global statement - is there a way of writing the code below without using global? I have tried doing this by putting the value of buttontwo in to the button_one_function parentheses but this didnt work. Thanks for any tips
from tkinter import *
my_window = Tk()
my_frame = Frame(my_window, height=500, width=500, bd='4')
my_frame.grid(row=0, column=0)
def button_one_function():
if button_two == 2:
print('do nothing')
else:
label_one = Label(my_frame, text='label one')
label_one.grid(row=1, column=0, sticky='n')
def button_two_function():
global button_two
button_two = 2
label_two = Label(my_frame, text='label two')
label_two.grid(row=1, column=1, sticky='n')
return button_two
button_one = Button(my_frame, text='button1', command=button_one_function)
button_one.grid(row=0, column=0)
button_two = Button(my_frame, text='button2', command=button_two_function)
button_two.grid(row=0, column=1)
my_window.mainloop()
If I've understood corectly, you are interested in sth. like this:
from tkinter import *
root = Tk()
def click(a):
print(a)
Button(root, text='1', command=lambda: click('1')).pack()
Button(root, text='2', command=lambda: click('2')).pack()
root.mainloop()
What is happening is I'm not passing a full click function to a button, but a so called lambda function, which is essentially a one-line function. Example: if I did p = lambda: print('Hi') then each time I do p() I would see a little Hi pop up. Also, if I did k = lambda a,b: a*b then k(4,5) would return "20". More info about lambdas here.
Hope that's helpful!
def function(a,b):
print("a is :",a)
print("b is :",b)
function(10,20)
You can definitely do this without globals. You could extend the tk.button class to hold a variable like self.status = pressed.
There are a few ways you can go about this with classes. You could create either one or two classes. Maybe even have child classes for each button.
But you can just dump both your functions in one class and pass self as its first argument.
Whenever I feel the need for a global variable, I usually make a class.
So, i know there has got to be a way to do this iv'e literally been trying all day to figure a solution and this is the closest i've come to getting it. The code works but the flaw is that it never reaches the else if statement because whatever button click is first in the statement will always be True hence it will never reach else if. Is their some way to combine the first two statements of my code into one because i believe that would solve it? This is using the tkinter GUI.
self.label1.bind("<Double-Button-1>",self._two_click)
self.label1.bind("<Button-1>", self._two_click)
def _two_click(self,event):
if self.label1.bind("<Button-1>"):
self.label1.configure(self.my_timeBB())
elif self.label1.bind("<Double-Button-1>"):
self.label1.configure(text="Blue")
I use extra argument in function to recognize click.
BTW: you can always bind <Button-1> and <Double-Button1> to one widget but with different functions ?
import Tkinter as tk
def test(event, extra=None):
print extra
master = tk.Tk()
b1 = tk.Button(master, text="QUIT", command=master.destroy, width=20, heigh=5)
b1.pack()
b2 = tk.Label(master, text="OK", width=20, heigh=5)
b2.pack()
b2.bind('<Double-Button-1>', lambda event:test(event,101))
b2.bind('<Button-1>', lambda event:test(event,1))
b2.bind('<Button-2>', lambda event:test(event,2))
b2.bind('<Button-3>', lambda event:test(event,3))
master.mainloop()
But I see one (big) problem - when I try to make double-click with my mouse I always get two text - first for single-click and second for double-click.
The only solution can be measure time between click and decide whether choose single or double click. But probably it will need to use after() too.
EDIT:
run only single or double clik
import Tkinter as tk
#----------------------------------------------------------------------
single = False
def test(event, extra=None):
global single
#print 'event-num:', event.num
#print 'extra:', extra
if extra == 1:
single = True
master.after(200, single_click)
elif extra == 101:
single = False
click('double click')
def single_click():
global single
if single:
single = False
click('single click')
def click(msg):
print 'It was', msg
#----------------------------------------------------------------------
master = tk.Tk()
b1 = tk.Button(master, text="QUIT", command=master.destroy, width=20, heigh=5)
b1.pack()
b2 = tk.Label(master, text="OK", width=20, heigh=5)
b2.pack()
b2.bind('<Double-Button-1>', lambda event:test(event,101))
b2.bind('<Button-1>', lambda event:test(event,1))
master.mainloop()