tkinter entry allows blank submissions and having to manually erase-CodePudding

Okay so the script runs where you type a entry press submit and a pop-up window shows what was typed. I have two issues I'd like help figuring out. Blank submissions and clearing the text after hitting submit.

Blank submission: input1: hello input2: world input3: "nothing typed" input4:hello world I get a blank line on input 3 but I don't want anything to happen(no error message needed) I tried to add .strip() but that didn't work / I didn't put it in correctly I tried it on the end of line 13 name=entry.get().strip and I tried adding a line entry.strip()

Clearing text: input1: welcome input2: to input3:python I have to manually erase the text inputs for the entry widget before I can type the next line

import tkinter as tk

flag = False
win=""

def setflag(event):
    global flag
    flag = False
    
#function that prints the entry
def entry_function(e=None):
    global flag,win
    name = entry.get()
    if not flag:
        win = tk.Toplevel()
        win.geometry('100x100')
        win.bind('<Destroy>', setflag)
        tk.Label(win, text=name).pack()
        flag = True
        win.geometry(" %d %d" % (x   600, y   300))
    else:
        tk.Label(win, text=name).pack()
     

 #Setup for the window
window = tk.Tk()
window.title("Title_Name")
window.geometry("500x500")
window.bind('<Return>', entry_function)
x = window.winfo_x()
y = window.winfo_y()

#widgets
label = tk.Label(window, text = "Manual:", bg = "dark grey", fg = "white")
entry = tk.Entry(window)
button = tk.Button(window,text = "submit",
                   command = entry_function)

#widget placement
label.place(x=0,y=20)
entry.place(x=52,y=21)
button.place(x=177, y=18)

window.mainloop()

CodePudding user response：

Made some changes to the code (explanation in code comments):

import tkinter as tk


# no need to use flag because just change win to None
# and check if it is None rather than using an 
# additional variable
win = None


# this would set win variable to None
def set_win_none(event=None):
    global win
    win = None


def entry_function(event=None):
    global win
    name = entry.get()
    
    # check if the string is empty, if so
    # stop the function
    if not name:
        return
    # clear the entry
    entry.delete('0', 'end')
    
    # as mentioned win can be used, it just shortens the code
    if win is None:
        win = tk.Toplevel()
        # set geometry as needed, this
        # will place the window
        # on the right of the main window
        win.geometry(f'100x100 {window.winfo_x()   window.winfo_width()} {window.winfo_y()}')
        win.bind('<Destroy>', set_win_none)
        tk.Label(win, text=name).pack()
    else:
        tk.Label(win, text=name).pack()


window = tk.Tk()

label = tk.Label(window, text="Manual:", bg="dark grey", fg="white")
entry = tk.Entry(window)
button = tk.Button(window, text="submit", command=entry_function)

# better bind the return key to the entry since it is
# directly involved
entry.bind('<Return>', entry_function)

# very rarely do you need to use .place
# better use .grid or .pack
label.grid(row=0, column=0, padx=5)
entry.grid(row=0, column=1, padx=5)
button.grid(row=0, column=2, padx=5)

window.mainloop()

There is rarely a need to use .place, better use .grid or .pack method for placing widgets, they are far more dynamic and adjust to how the window changes.

Also:
I strongly suggest following PEP 8 - Style Guide for Python Code. Function and variable names should be in snake_case, class names in CapitalCase. Don't have space around = if it is used as a part of keyword argument (func(arg='value')) but have space around = if it is used for assigning a value (variable = 'some value'). Have space around operators ( -/ etc.: value = x y(except here value = x y)). Have two blank lines around function and class declarations.