I am simply trying to move class ScreenThree to a separate file 9 I will soon have many more)....However for the lambdas I get nameError ...how to fix?
I've tried many arrangements, but allways get some sort of nameError. For this post, I have deleted ScreenTwo, since these basically all look the same. When moving this class to its own file what needs to be changed? I used import, which seemed to work & screen3 shows. , However the button lambda is where it fails import tkinter as tk
LARGE_FONT = ("Verdana", 12) # font's family is Verdana, font's size is 12
class MainWindow(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.title("Fuzzy System") # set the title of the main window
self.geometry("300x300") # set size of the main window to 300x300 pixels
# this container contains all the screens
container = tk.Frame(self)
container.pack(side="top", fill="both", expand=True)
container.grid_rowconfigure(0, weight=1) # make the cell in grid cover the entire window
container.grid_columnconfigure(0,weight=1) # make the cell in grid cover the entire window
self.frames = {} # these are screens we want to navigate to
for F in (ScreenOne, ScreenTwo,ScreenThree): # for each screen
frame = F(container, self) # create the screen
self.frames[F] = frame # store into frames
frame.grid(row=0, column=0, sticky="nsew") # grid it to container
self.show_frame(ScreenOne) # let the first screen is ScreenOne
def show_frame(self, name):
frame = self.frames[name]
frame.tkraise()
class ScreenOne(tk.Frame):
def __init__(self, parent, controller):
self.controller=controller
tk.Frame.__init__(self, parent)
label = tk.Label(self, text='This is ScreenOne', font=LARGE_FONT)
label.pack(pady=10, padx=10) # center alignment
# when click on this button, call the show_frame method to make screenOne appear
button1 = tk.Button(self, text='Visit screen two', command=lambda : controller.show_frame(ScreenTwo))
button1.pack() # pack it in
self.button2 = tk.Button(self, text='GOTO Screen Three', command=lambda : controller.show_frame(ScreenThree))
self.button2.place(relx=0.5, rely=0.29, height=41, width=144)
self.button2.configure(background="#911218")
class ScreenThree(tk.Frame):
def __init__(self, parent, controller):
self.controller=controller
tk.Frame.__init__(self, parent)
label = tk.Label(self, text='This is screen Three', font=LARGE_FONT)
label.pack(pady=10, padx=10)
button1 = tk.Button(self, text='GOTO ScreenTwo', command=lambda : controller.show_frame(ScreenTwo))
button1.pack()
button2 = tk.Button(self, text='GOTO Screen One', command=lambda : controller.show_frame(ScreenOne))
button2.pack()
if __name__ == '__main__':
app = MainWindow()
app.mainloop()
I have several classes, all looking similar to the following. They all work fine, no problems. However I want to move them to individual files, since they will soon become lengthy. I moved the following to file `scr3.py`.
I then added the following to my main file:
from scr3 import ScreenThree
Screen one and two work fine and my buttons in `screen3` show up. However when pushing on the screen three buttons I get a `NameError: name 'ScreenOne' is not defined` and similar for `screen2` (see the lambda funcs). These worked fine when all was in one file. `Screen1` and `2` (still in the `main` file) continue to work fine.
Why does it work fine when this same code is in the `main` file , but now fails? It has only been moved. What is the workaround?
import tkinter as tk
LARGE_FONT = ("Verdana", 12) # font's family is Verdana, font's size is 12
class ScreenThree(tk.Frame):
def __init__(self, parent, controller):
self.controller=controller
tk.Frame.__init__(self, parent)
label = tk.Label(self, text='This is screen Three', font=LARGE_FONT)
label.pack(pady=10, padx=10)
button1 = tk.Button(self, text='GOTO ScreenTwo', command=lambda : controller.show_frame(ScreenTwo))
button1.pack()
button2 = tk.Button(self, text='GOTO Screen One', command=lambda : controller.show_frame(ScreenOne))
button2.pack()
