I wanted to create an app to calculate the total number of grids, by getting the number of grids in X,Y, and Z directions. I also want to use the result to be moved in the next windows. I found this post below, and I used it as my code basis.
I could write my code to calculate the total grids and show it in the next window.
import tkinter as tk
class Data:
def __init__(self):
self.nx = tk.IntVar()
self.ny = tk.IntVar()
self.nz = tk.IntVar()
self.Tot_grids = tk.IntVar()
self.A = tk.IntVar()
class SampleApp(tk.Tk):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.title("Test app")
self.geometry("400x400")
container = tk.Frame(self)
container.pack()
self.data = Data()
self.frames = {}
for F in (PageOne, PageTwo):
frame = F(container, self.data)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky="nsew")
self.frames[PageOne].button4_P1.config(command=self.go_to_page_two)
self.show_frame(PageOne)
def go_to_page_two(self):
self.show_frame(PageTwo)
def show_frame(self, c):
frame = self.frames[c]
frame.tkraise()
class PageOne(tk.Frame):
def __init__(self, parent, data):
super().__init__(parent)
self.data = data
self.frame_1 = tk.Frame(self)
self.frame_1.grid(row=0, column=0)
self.label_1 = tk.Label(self.frame_1, text="nx")
self.label_1.grid(row=0, column=0)
self.entry_1 = tk.Entry(self.frame_1, textvariable=data.nx)
self.entry_1.grid(row=0, column=1)
self.label_2 = tk.Label(self.frame_1, text="ny")
self.label_2.grid(row=1, column=0)
self.entry_2 = tk.Entry(self.frame_1, textvariable=data.ny)
self.entry_2.grid(row=1, column=1)
self.label_3 = tk.Label(self.frame_1, text="nz")
self.label_3.grid(row=2, column=0)
self.entry_3 = tk.Entry(self.frame_1, textvariable=data.nz)
self.entry_3.grid(row=2, column=1)
def total_grids():
nt = data.nx.get() * data.ny.get() * data.nz.get()
self.label_4.config(text=str(nt))
data.Tot_grids.set(nt)
self.button1 = tk.Button(self.frame_1, text="Calculate", command=total_grids)
self.button1.grid(row=3, column=0, columnspan=2)
self.button4_P1 = tk.Button(self.frame_1, text="Continue")
self.button4_P1.grid(row=5, column=0, columnspan=4, pady=5)
self.label_4 = tk.Label(self.frame_1)
self.label_4.grid(row=4, column=0, columnspan=2)
class PageTwo(tk.Frame):
def __init__(self, parent, data):
super().__init__(parent)
self.data = data
self.frame2 = tk.Frame(self)
self.frame2.pack()
self.label_5 = tk.Label(self.frame2, textvariable=self.data.Tot_grids)
self.label_5.pack()
app = SampleApp()
app.mainloop()
But, I don't know how to use it for further calculations. assume I want to do a simple calculation and add the passed variable by 100. I added a few lines to do that in class PageTwo, but it gives me an error.
import tkinter as tk
class Data:
def __init__(self):
self.nx = tk.IntVar()
self.ny = tk.IntVar()
self.nz = tk.IntVar()
self.Tot_grids = tk.IntVar()
self.A = tk.IntVar()
class SampleApp(tk.Tk):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.title("Test app")
self.geometry("400x400")
container = tk.Frame(self)
container.pack()
self.data = Data()
self.frames = {}
for F in (PageOne, PageTwo):
frame = F(container, self.data)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky="nsew")
self.frames[PageOne].button4_P1.config(command=self.go_to_page_two)
self.show_frame(PageOne)
def go_to_page_two(self):
self.show_frame(PageTwo)
def show_frame(self, c):
frame = self.frames[c]
frame.tkraise()
class PageOne(tk.Frame):
def __init__(self, parent, data):
super().__init__(parent)
self.data = data
self.frame_1 = tk.Frame(self)
self.frame_1.grid(row=0, column=0)
self.label_1 = tk.Label(self.frame_1, text="nx")
self.label_1.grid(row=0, column=0)
self.entry_1 = tk.Entry(self.frame_1, textvariable=data.nx)
self.entry_1.grid(row=0, column=1)
self.label_2 = tk.Label(self.frame_1, text="ny")
self.label_2.grid(row=1, column=0)
self.entry_2 = tk.Entry(self.frame_1, textvariable=data.ny)
self.entry_2.grid(row=1, column=1)
self.label_3 = tk.Label(self.frame_1, text="nz")
self.label_3.grid(row=2, column=0)
self.entry_3 = tk.Entry(self.frame_1, textvariable=data.nz)
self.entry_3.grid(row=2, column=1)
def total_grids():
nt = data.nx.get() * data.ny.get() * data.nz.get()
self.label_4.config(text=str(nt))
data.Tot_grids.set(nt)
self.button1 = tk.Button(self.frame_1, text="Calculate", command=total_grids)
self.button1.grid(row=3, column=0, columnspan=2)
self.button4_P1 = tk.Button(self.frame_1, text="Continue")
self.button4_P1.grid(row=5, column=0, columnspan=4, pady=5)
self.label_4 = tk.Label(self.frame_1)
self.label_4.grid(row=4, column=0, columnspan=2)
class PageTwo(tk.Frame):
def __init__(self, parent, data):
super().__init__(parent)
self.data = data
self.frame2 = tk.Frame(self)
self.frame2.pack()
self.label_5 = tk.Label(self.frame2, textvariable=self.data.Tot_grids)
self.label_5.pack()
self.data.A = self.data.Tot_grids 100
self.label_6 = tk.Label(self.frame2, textvariable=self.data.A)
self.label_6.pack()
app = SampleApp()
app.mainloop()
I also have this question, do we really need to use self before every label, entry fields, or button. I removed some of them, and the code was working for my code. Does removing them cause problems later?
CodePudding user response：
You can us tkinter variable .trace() to update Data.A whenever Data.tot_grids is updated:
class PageTwo(tk.Frame):
def __init__(self, parent, data):
super().__init__(parent)
self.data = data
self.frame2 = tk.Frame(self)
self.frame2.pack()
self.label_5 = tk.Label(self.frame2, textvariable=self.data.Tot_grids)
self.label_5.pack()
self.label_6 = tk.Label(self.frame2, textvariable=self.data.A)
self.label_6.pack()
# call on_grids_updated() whenever Data.Tot_grids is updated
self.data.Tot_grids.trace_add('write', self.on_grids_updated)
def on_grids_updated(self, *args):
self.data.A.set(self.data.Tot_grids.get() 100)
For question on using self, if the variable will be accessed in other class methods, then you need to prefix it with self. to make it an instance variable, otherwise the prefix is not necessary.