how to refresh the window in python - python

I have a function which will display features of an image. Once it got displayed, I want to refresh it for the next image.
For instance if I have a window like this
Once I click on the Refresh Button the window should be like this
Initially every feature values are set to zero.
How to achieve this? I have tried with grid_forget() it will not give me what I wanted. I don't want to clear the window, I just want to clear the entries in each of the Entry box, and I want to clear the Label too, so that I can select another image
Thanks in advance!

If you have a lot of Entry widgets, like in your example, you can use the winfo_children() method to get a list of all the children widgets of an object. Then, you can iterate through this list to reset and configure the widgets it contains:
root = Tk()
def clear_all():
for widget in root.winfo_children(): # get all children of root
if widget.winfo_class() == 'Entry': # if the class is Entry
widget.delete(0,END) # reset its value
elif widget.winfo_class() == 'Label': # get Label widgets
widget.config(bg='green') # and change them as well
# set up misc. widgets
for i in range(5):
Entry(root).pack()
Label(root, height=10, width=100, bg='red').pack()
Button(root, text='Refresh', command=clear_all).pack()
mainloop()

All you need to do is set the entry widgets to whatever default values you want:
# if you do not use the textvariable attribute:
self.entry1.delete(0, "end")
self.entry1.insert(0, "0")
self.entry2.delete(0, "end")
self.entry2.insert(0, "0.0")
# if you DO use the textvariable attribute:
self.entry1var.set("0")
self.entry2var.set("0.0")
This is all documented on the Entry man page, and in most tkinter tutorials. A good place to start when researching how to use individual widgets is effbot.org. For example, here is their page on the Entry widget: http://effbot.org/tkinterbook/entry.htm

Related

How can I set the order of duplicated widgets in tkinter, python?

I use image(image1) for background and made Entry with create_window method.
And I want to make image(image2) cover the entry with create_image method.
But the Entry widget is revealed everytime.(Entry - image2 - imgae1)
How can I change the order of these like image2- Entry - image1.
My code is like below.
self.img_main = PhotoImage(file=r"C:\Bart\My library\Python\Grinding\GUI\capture\image1.png")
self.canvas_main = Canvas(self, width=1366, height=768, bd=0)
self.canvas_main.pack(fill=BOTH, expand=True)
self.canvas_main.create_image(0,0, image=self.img_main, anchor=NW)
self.entry = Entry(self, width=12, justify="center", bg="#A5C1DE")
self.canvas_main.create_window(72, 287, height=32, anchor=NW, window=self.entry)
self.cbb_pro_sel_img_1 = PhotoImage(file=r"C:\Bart\My library\Python\Grinding\GUI\capture\image2.png")
self.cbb_pro_sel = self.canvas_main.create_image(36, 75, anchor=NW, image=self.cbb_pro_sel_img_1)
You cannot raise an image object on a canvas above an embedded widget. From the canvas documentation:
The items in a canvas are ordered for purposes of display, with the first item in the display list being displayed first, followed by the next item in the list, and so on. Items later in the display list obscure those that are earlier in the display list and are sometimes referred to as being “on top” of earlier items. When a new item is created it is placed at the end of the display list, on top of everything else. Widget commands may be used to re-arrange the order of the display list. Window items are an exception to the above rules. The underlying window systems require them always to be drawn on top of other items.
Instead, you can create a label that contains the image and then use create_window to put the label over the entry. Since it is a widget, it can appear above the entry widget.

How do I remove focus and cursor on my entry widget in Tkinter? [duplicate]

I'd like to remove focus from a widget manually.
You can focus to another dummy widget.
Edit
from Tkinter import *
def callback():
print master.focus()
master = Tk()
e = Entry(master)
e.pack()
e.focus()
b = Button(master, text="get", width=10, command=callback)
b.pack()
master.mainloop()
Focusing on a non-'focusable' widget will remove focus from another widget.
Set focus to another widget to remove focus from the target widget is a good idea. There are two methods for this: w.focus_set() and w.focus_force(). However, method w.focus_force() is impolite. It's better to wait for the window manager to give you the focus. Setting focus to parent widget or to the root window removes focus from the target widget.
Some widgets have takefocus option. Set takefocus to 0 to take your widget out of focus traversal (when user hits <Tab> key).
My solution is root.focus() it will remove widget focus.
If the dummy widget is Canvas then c.focus() will not work.
use c.focus_set() or c.tk.call('focus',c) to first focus on the canvas window itself.
That's because
c.focus()
... returns the id for the item that currently has the focus, or an empty string if no item has the focus. Reference
c.focus(id_) will focus on the item having id id_ within the canvas.
c.focus("") will remove the focus from any item in the canvas.
Hence (within some callback)
c.config(highlightthickness = 0) # to remove the highlight border on focus
c.foucs_set()
c.focus("") # just to be sure
The reason c.focus() functions differently is that within Tcl/Tk's Commands there's the "Primary" Command focus
as well as the Canvas-specific Widget Command focus
That's not an issue within the Tcl/Tk syntax but in the tkinter module c.focus() will call the underlying canvas-specific foucs.
From tkinter.py within the Canvas class Line 2549
def focus(self, *args):
"""Set focus to the first item specified in ARGS."""
return self.tk.call((self._w, 'focus') + args)
So the question may be a duplicate here, but the answer from #Bryan Oakley works perfectly for me in Python 3.8
root.focus_set()
Too easy...
If you use ttk widgets you can "remove" the focus ring by removing the color; for example on a button:
style = ttk.Style()
style.configure('TButton', focuscolor='')

Tkinter Python listbox

I am a new python user. I'm used to programing on matlab.
I've trying to make a simple GUI with Tkinter pack, but I'm having some problems with that. I had already read and searched what i want but I couldn't develop it.
What I'm trying to do is to make a listbox and when I choose one (or more) options the index be returned (and stored) as a variable (array or vector) that could be used to indexing another array.
The best result I got was a listbox where the index were printed, but not stored as a variable (at least it hasn't been shows in the variables list)
I'm using spyder (anaconda).
I tryied a lot of codes and I don't have this anymore.
Sorry for the dumb question. I guess I still thinking in a Matlab way to write
To keep this application simple, your best option is to get the listbox selection when you want to do something with it:
from tkinter import Tk, Listbox, MULTIPLE, END, Button
def doStuff():
selected = lb.curselection()
if selected: # only do stuff if user made a selection
print(selected)
for index in selected:
print(lb.get(index)) # how you get the value of the selection from a listbox
def clear(lb):
lb.select_clear(0, END) # unselect all
root = Tk()
lb = Listbox(root, selectmode=MULTIPLE) # create Listbox
for n in range(5): lb.insert(END, n) # put nums 0-4 in listbox
lb.pack() # put listbox on window
# notice no parentheses on the function name doStuff
doStuffBtn = Button(root, text='Do Stuff', command=doStuff)
doStuffBtn.pack()
# if you need to add parameters to a function call in the button, use lambda like this
clearBtn = Button(root, text='Clear', command=lambda: clear(lb))
clearBtn.pack()
root.mainloop()
I've also added a button to clear the listbox selection because you cannot unselect items by default.
First, import tkinter, then, create the listbox. Then, you can use curselection to get the contents of the listbox.
import tkinter as tk
root = tk.Tk() #creates the window
myListbox = tk.Listbox(root, select=multiple) #allows you to select multiple things
contentsOfMyListbox = myListbox.curselection(myListbox) #stores selected stuff in tuple
See the documentation here.

How to create a combobox that includes checkbox for each item?

Fairly new to tkinter and python I was wondering how to achieve a button that would act like this :
Click on button drops down a list (so that's a combobox)
Each line of the list has a checkbox.
Finally if a checkbox is clicked run a function, or (even better) once combobox is no more dropped run a function with items checked as args.
UPDATE
The button/menuButton will have to act like a filter. When menu is dropped down user can uncheck multiple options (without the menu to disappear each time an item is clicked) he don't want. Therefore it's really important to be able to see checkboxes so as the user know which options are currently active.
I finally used the idea of Bryan by creating a top level frame. Here is what I have :
There is no widget to do what you want. You'll have to create a toplevel window with a bunch of checkbuttons. You can then trigger the appearance with a normal button.
I don't think the OptionMenu is intended to hold anything but strings. It sounds like you want the functionality of a Listbox, which has options to allow for multiple selections, get all selected items, and so on.
This gives you an OptionMenu with checkboxes in the contained Menu. Check whichever items you like, then right-click in the tkinter window to print the values of the checkboxes to the console.
from tkinter import *
master = Tk()
var = StringVar(master)
var.set("Check")
w = OptionMenu(master, variable = var, value="options:")
w.pack()
first = BooleanVar()
second = BooleanVar()
third = BooleanVar()
w['menu'].add_checkbutton(label="First", onvalue=True,
offvalue=False, variable=first)
w['menu'].add_checkbutton(label="Second", onvalue=True,
offvalue=False, variable=second)
w['menu'].add_checkbutton(label="Third", onvalue=1,
offvalue=False, variable=third)
master.bind('<Button-3>', lambda x: print("First:", first.get(), " Second:",
second.get(), " - Third:", third.get()))
mainloop()
See also this.

Python - TKinter - Editing Widgets

I need a widget in TKinter to be a global widget, however, I need the text displayed in it to be different every time. I'm quite new with TKinter and haven't yet successfully managed to edit an option in a widget.
I assume it's something to do with widget.add_option() but the documentation is quite confusing to me and I can't figure out the command.
I specifically just need to edit the text = "" section.
Thanks
EDIT:
gm1_b_current_choice_label = Label(frame_gm1_b, text = "Current input is:\t %s"% str(save_game[6]))
I specifically need to update the save_game[6] (which is a list) in the widget creation, but I assume once the widget is created that's it. I could create the widget every time before I place it but this causes issues with destroying it later.
You can use the .config method to change options on a Tkinter widget.
To demonstrate, consider this simple script:
from Tkinter import Tk, Button, Label
root = Tk()
label = Label(text="This is some text")
label.grid()
def click():
label.config(text="This is different text")
Button(text="Change text", command=click).grid()
root.mainloop()
When the button is clicked, the label's text is changed.
Note that you could also do this:
label["text"] = "This is different text"
or this:
label.configure(text="This is different text")
All three solutions ultimately do the same thing, so you can pick whichever you like.
You can always use the .configure(text = "new text") method, as iCodez suggested.
Alternatively, try using a StringVar as the text_variable parameter:
my_text_var = StringVar(frame_gm1_b)
my_text_var.set("Current input is:\t %s"% str(save_game[6]))
gm1_b_current_choice_label = Label(frame_gm1_b, textvariable = my_text_var)
Then, you can change the text by directly altering my_text_var:
my_text_var.set("Some new text")
This can be linked to a button or another event-based widget, or however else you want to change the text.

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