first of all I'm new to Python and coding overall.
I wanna ask, I'm using IDLE and Tkinter together. I'm making a simple calculator.
def getInput():
i1 = Input1_Box.get()
i2 = Input2_Box.get()
i3 = Input3_Box.get()
calculate = float(i1) * float(i3) - float(i2) * float(i3)
print(calculate)
Here I use define tag getInput to fetch data from Entry widget and use the string(I think so), calculate to put a simple equation to calculate all the data fetch.
But I don't know how to display the result of "calculate" into and Entry widget or display as a text.
To quote Bryan Oakley from this question and BuvinJ from this question:
For an entry widget you have two choices. One, if you have a textvariable associated, you can call set on the textvariable. This will cause any widgets associated with the textvariable to be updated. Second, without a textvariable you can use the insert and delete methods to replace what is in the widget.
Here's an example of the latter:
calculateEntry.delete(0, "end")
calculateEntry.insert(0, calculate)
And for the former:
If you use a "text variable" tk.StringVar(), you can just set() that.
No need to use the Entry delete and insert. Moreover, those functions don't work when the Entry is disabled or readonly! The text variable method, however, does work under those conditions as well.
calculateVar = tk.StringVar()
calculateEntry = tk.Entry( master, textvariable=calculateVar )
calculateVar.set( calculate )
Related
def openCipher():
cipher = Toplevel()
cipher.title("decryptt - CIPHER")
cipherLabel = Label(cipher, text="cipher").pack()
cipherEntry = Entry(cipher, width=20, borderwidth=5) #separating pack now allows you to use get() on this
cipherEntry.pack()
cipherChoices = [
("Binary","bcipher"),
("Caesar","ccipher"),
("Hexadecimal","hcipher"),
("Atbash","acipher"),
("Letter-to-Number","lcipher")
]
cipherType = StringVar()
cipherType.set("Binary")
for text, cipherChoice in cipherChoices:
Radiobutton(cipher, text=text, variable=cipherType, value=cipherChoice).pack()
cipherButton = Button(cipher, text="Cipher", padx=10, pady=5, command=lambda:[ciphering(cipherEntry.get()), ciphering(cipherChoice.get())]).pack() #lambda allows you to pass arguments to functions
quitButton = Button(cipher, text="Exit Cipher", padx=10, pady=5, command=cipher.destroy).pack()
# This is the function that is suppose to split the input from cipherEntry into individual characters in an array.
def ciphering(entry,choice):
ciphering = Toplevel() #needed to add new label to
cipherLabeling = Label(ciphering, text = "You have inputted " + entry).pack() #couldn’t add a list to string like that, nor use get() on a list, changed to just use the string
seperatedWord = list(entry)
cipherLabeling = Label(ciphering, text = seperatedWord[2]).pack()
seperatedWordLength = len(seperatedWord)
cipherLabeling = Label(ciphering, text = seperatedWordLength).pack()
selection = Label(ciphering, text = choice).pack()
Above is part of the code I have for my ciphering app I am making in Tkinter. Took out the less important parts.
Basically, what is being created in OpenCipher() functions is an entry box that is named cipherEntry. Then there are radio buttons with different names of different ciphers and the value and variable of each radio button is the same as each other for that radio button. Then there is another button that takes whatever cipherEntry is and brings it to another window using the ciphering() function.
What I need to know is how do I also get whatever the value and/or variable of whatever radio button they have selected to that window using the same button they pressed to get to that window ( cipherButton ). Because I want to then use their selection and input to know what cipher type they want their input to be changed to. I already have the function for it sorted.
I have tried using cipherType, cipherChoice, cipherChoices but have no idea how to get them both in there. With the current code above. It works as if there was no second command. It totally disregards whatever selection I put in and the 'selection' label widget doesn't display their choice. I have also made each variable a global to see if that did anything but no luck.
I would really appreciate any assistance :)
First of all, the code should give an error because def ciphering(entry,choice) expects two positional arguments to be passed at the same time. Even after fixing that, it should give another error because cipherChoice is a string(from the list of tuples) and does not have a get attribute.
The thing to focus on here is:
command=lambda: [ciphering(cipherEntry.get()), ciphering(cipherChoice.get())]
When you say something like lambda: [func1(arg1),func1(arg2)] you are set to executing the function func1 and again func1 one after the other(so twice). What you want is to pass multiple arguments to the same function just using a normal lambda without any list, like:
command=lambda: ciphering(cipherEntry.get(), cipherType.get())
Also notice how I changed cipherChoice.get() to cipherType.get(), it is because cipherChoice is a string and also does not have a get attribute, but the value of the radiobutton should be acquired from the associated tkinter variable(StringVar) only. So you have to use cipherType.get()
Tkinter Requirements
So I am relatively new to using tkinter and I am struggling with a very specific doubt here. I tried finding solutions to this but as much as I find it obvious, the solution to this doesn't seem to be easy to understand. So if you can see the image above, I am trying to create a GUI for a particular project which requires multi-layer (I am calling it 3D array based) widgets.
Let's say the variables used for this pointer system are i, j, and k.
I am creating individual layer widgets using for loop:
for n in range(i):
frame_x[i] = Frame(root).grid(row = 1, column = i)
entry_x[i] = Entry(frame_x[i]).grid(row = 2, column = i)
button_x[i] = Button(frame_x[i]).grid(row=3, column = i)
Please note this is not a functional code, I have tried to keep it to the point just to give an idea of the method I am using. (Let me know if you want a more detailed code block.)
Now coming to the problem. I am able to do the basic part of this. But the problem is that I want it to work dynamically.
Let's say if the user enters j = 4 first. 4 blocks will be created.
Later if he changes the value to j = 2 and the presses the button, ideally it should make the widgets at block j= 3 and 4 disappear. But I guess tkinter works on overlapping basis and doesn't change a grid element until something is specifically overlapped over it. How do I do that. I tried destroying the entire frame just after entering the for loop, but that doesn't work as for the first time no widget is created before destroying and python throws NameError saying I can't use a variable before assignment.
Anyways, please let me know how do I do this efficiently.
And also in general, if there is a better way to go about the whole thing. Please refer the image above and let me know if it doesn't make sense.
I am not very comfortable with classes in general. I prefer the inefficient way by only using functions to do everything I have to. So it would be great if you can share me a framework without using classes. But its okay if you use them. I know I should start working with classes at some point.
First off, I want to address this part of the question:
I guess tkinter works on overlapping basis and doesn't change a grid element until something is specifically overlapped over it.
I'm not entirely sure what you mean by that, but if it means what I think it means, it is a false statement. tkinter doesn't "work on an overlapping basis". If you destroy a widget, it is destroyed. It doesn't matter if it's overlapped or not.
Based on the tiny bit of code you posted, the main problem is that you aren't putting the entry and button in the frame. Because of that, they are not destroyed when you destroy the frame.
The reason you aren't putting the widgets into the frame is because of this line:
frame_x[i] = Frame(root).grid(row = 1, column = i)
In python, when you do x=y().z(), x has the value of z(). Thus, when you do frame_x[i] = Frame(...).grid(...), frame_x[i] has the value of .grid(...), and .grid(...) always returns None. Thus, frame_x[i] will be None.
When you next do entry_x[i] = Entry(frame_x[i]).grid(...), it's the same as doing entry_x[i] = Entry(None).grid(...). Because the master of the Entry is None, it becomes a child of the root window.
So, the first step is to separate the creation of the widget from the layout of the widget.
frame_x[i] = Frame(root)
frame_x[i].grid(row = 1, column = i)
Once you do that, the Entry and Button widgets will become a child of the frame, and you can remove widgets you don't want by destroying the frame (eg: frame_x[i].destroy()), since destroying a widget will also cause all children of the widget to be destroyed.
Once you have that in place, you can destroy unwanted widgets by simply calling .destroy() on the frame. For example, if you have previously created 10 groups and now need only 5, you can destroy the others and then remove them from the list like this:
# assume 'num' contains the number of frames that we want,
# and that it is smaller than the number of items in frames_x
for frame in frames_x[num:]:
frame.destroy()
frames_x = frames_x[:num]
Here is a complete working program to illustrate. Enter a number and click the button. It will create that many frame+entry+button combinations. Enter a new number that is larger or smaller and it will either add or remove widgets.
This would be easier if you used classes, but you specifically asked for a solution that doesn't use classes. In your real code you probably need to also save the entry widgets in an array so that you can reference them later, but this example is focuses on the creation of the widgets rather than writing your whole program for you.
import tkinter as tk
frames_x = [] def create_widgets():
global frames_x
num = int(num_widgets.get())
# if the number is less than the previous number of
# widgets, delete the widgets we no longer want
for frame in frames_x[num:]:
frame.destroy()
frames_x = frames_x[:num]
# if the number is greater than the previous number of
# widgets, create additional widgets
for i in range(len(frames_x), num):
# create new widget
frame = tk.Frame(root, bd=1, relief="raised")
entry = tk.Entry(frame)
button = tk.Button(frame, text="click me")
# pack entry and button in frame
button.pack(side="right")
entry.pack(side="left", fill="x", expand=True)
# grid the frame in the parent
frame.grid(row=i+1, column=0, columnspan=2)
# save the new frame in the array
frames_x.append(frame)
root = tk.Tk() num_widgets = tk.Entry(root) button = tk.Button(root, text="Create widgets", command=create_widgets)
button.grid(row=0, column=1) num_widgets.grid(row=0, column=0, sticky="ew")
root.mainloop()
I am new to tkinter. I want to write two numbers in two different entries in GUI and see their updated subtraction result on the display. here is my code:
from tkinter import *
window = Tk()
lb1 = Label(window,text="variable 1")
lb1.pack()
name1=IntVar()
en1=Entry(window, textvariable=name1)
en1.pack()
lb2 = Label(window,text="variable 2")
lb2.pack()
name2=IntVar()
en2=Entry(window, textvariable=name2)
en2.pack()
subt=IntVar()
subt=name1.get()-name2.get()
label_subt=Label(window, text=subt).pack()
how can I update label_subt?
You change the subt variable to the result of the subtraction before actually setting it to the label. Don't do that! Also, you set it as the text, not as the textvariable.
subt = IntVar()
Label(window, textvariable=subt).pack()
(Note that the result of pack() is not the Label, but None, so either move it to a separate line, as you did before, or just don't bind it to a variable that you never need anyway.)
Next, you can define a callback function for updating the value of the subt variable using the set method and bind that callback to any key press. You might want to narrow this down a bit, though.
def update(event):
subt.set(name1.get() - name2.get())
window.bind_all("<Key>", update)
You could try calling the config method on the label after every subtraction. You’ll have to use the entry.get() method to get the string of each entry. And don’t forget to use int() to convert it to an integer so you can do your subtraction otherwise you’ll get an error
label_subt.config(text=result)
How to create multi-lines in an entry widget in tkinter and use those inputs to create something?
For example, I want a textbox widget to come up and ask the user:
How many squares do you want? (ex: 4x4, 5x5)
What color do you want them?
And with the users input, I would like to create that many x-amount of squares in that specific height/width and specify the colors etc.
I am totally new to tkinter and I'm not really sure how to approach this.
I tried using this, but i'm not really sure how to add more lines and to use the values inputted.
import tkinter
from tkinter import *
class Squares:
root = Tk()
root.title('Random')
x = Label(text='How many squares? (ex: 4x4, 5x3)').pack(side=TOP,padx=10,pady=10)
Entry(root, width=10).pack(side=TOP,padx=10,pady=10)
Button(root, text='OK').pack(side= LEFT)
Button(root, text='CLOSE').pack(side= RIGHT)
You have a number of problems here.
I'm not sure what the Squares class is supposed to be doing, but it's basically not doing anything. You have a bunch of code that runs when you define the class, creating a few variables (which will end up as class attributes, shared by all instances of the class), and… that's it. Rather than try to figure out what you're intending here, I'm just going to scrap the class and make it all module-level code.
You never call root.mainloop(), so your program will just define a GUI and then never run it.
You don't bind your buttons to anything, so there's no way they can have any effect. You need to create some kind of function that does something, then pass it as the command argument, or .bind it later.
You don't store references for any of your controls, so there's no way to access them later. If you want to get the value out of the entry, you need some way to refer to it. (The exception is your x variable, but that's going to be None, because you're setting it to the result of calling pack on the Label, not the Label itself.)
Once you've done that, you just need to parse the value, which is pretty easy.
Putting it all together:
import tkinter
from tkinter import *
root = Tk()
root.title('Random')
Label(text='How many squares? (ex: 4x4, 5x3)').pack(side=TOP,padx=10,pady=10)
entry = Entry(root, width=10)
entry.pack(side=TOP,padx=10,pady=10)
def onok():
x, y = entry.get().split('x')
for row in range(int(y)):
for col in range(int(x)):
print((col, row))
Button(root, text='OK', command=onok).pack(side=LEFT)
Button(root, text='CLOSE').pack(side= RIGHT)
root.mainloop()
You just have to change that print to do something useful, like creating the squares.
If you don't need an outline for the text box, create_text would be the easiest thing, even though it doesn't have a wrap text feature(at least, in python 3 you can do this):
from tkinter import *
tk = Tk()
canvas = Canvas(tk, 1000, 1000)
canvas.pack()
canvas.create_text(200, 200, text="Example Text")
Try it!
I'm trying to associate a variable with a Tkinter entry widget, in a way that:
Whenever I change the value (the "content") of the entry, mainly by typing something into it, the variable automatically gets assigned the value of what I've typed. Without me having to push a button "Update value " or something like that first.
Whenever the variable gets changed (by some other part of the programm), I want the entry value displayed to be adjusted automatically. I believe that this could work via the textvariable.
I read the example on http://effbot.org/tkinterbook/entry.htm, but it is not exactly helping me for what I have in mind. I have a feeling that there is a way of ensuring the first condition with using entry's "validate". Any ideas?
I think you want something like this. In the example below, I created a variable myvar and assigned it to be textvariable of both a Label and Entry widgets. This way both are coupled and changes in the Entry widget will reflect automatically in Label.
You can also set trace on variables, e.g. to write to stdout.
from tkinter import *
root = Tk()
root.title("MyApp")
myvar = StringVar()
def mywarWritten(*args):
print "mywarWritten",myvar.get()
myvar.trace("w", mywarWritten)
label = Label(root, textvariable=myvar)
label.pack()
text_entry = Entry(root, textvariable=myvar)
text_entry.pack()
root.mainloop()