I was creating a program that lets you enter a date into the GUI and it spits out a label showing the day of the week of said date. Every single time i run the program more than once, it doesn't delete the previous label. If i put in an invalid date and day_of_week comes back as "INVALID" and then I run it again and get "monday", It would put the monday label in front of "INVALID" instead of deleting "INVALID". How do I delete the previous label after every button click so there is no weird overlap?

    from tkinter import *
    import datetime
    
    #Declares the gui
    root = Tk()
    
    #dimensions of the gui
    win_dimensions = '200x100'
    
    def find_day(day,month,year):
        try:
            #cast year as an integer
            year = int(year)
            #turn it into a datetime variable
            date = datetime.date(year,month,day)
        except:
            day_of_week = Label(root,text="INVALID DATE",fg="RED")
        else:
            weekday = date.weekday()
            #find the day of week
            if weekday == 0:
                day_of_week = Label(root,text="Monday")
            if weekday == 1:
                day_of_week = Label(root,text="Tuesday")
            if weekday == 2:
                day_of_week = Label(root,text="Wednesday")
            if weekday == 3:
                day_of_week = Label(root,text="Thursday")
            if weekday == 4:
                day_of_week = Label(root,text="Friday")
            if weekday == 5:
                day_of_week = Label(root,text="Saturday")
            if weekday == 6:
                day_of_week = Label(root,text="Sunday")
        finally:
            day_of_week.grid(column=1,row=4)    
    
    
    def main():
        
        #title of the pop up window
        root.title(" ")
    
        #creates and locks the dimensions of the window
        root.geometry(win_dimensions)
        root.maxsize(win_dimensions.split("x")[0],win_dimensions.split("x")[1])
        root.minsize(win_dimensions.split("x")[0],win_dimensions.split("x")[1])
    
        #label for month
        month_label = Label(root,text="Month:")
        month_label.grid(column=0,row=1)
    
        #create dropdown menu for month
        mon = IntVar()
        mon.set(1)
        month_num = list(range(1,13))
        month = OptionMenu(root,mon,*month_num)
        month.grid(column=0,row=2,padx=2)
    
        #label for day
        day_label = Label(root,text="Day:")
        day_label.grid(column=1,row=1)
    
        #create dropdown menu for day
        dy = IntVar()
        dy.set(1)
        day_num = list(range(1,32))
        day = OptionMenu(root,dy,*day_num)
        day.grid(column=1,row=2)
    
        #create label for year
        year_label = Label(root,text="Year:")
        year_label.grid(column=2,row=1)
    
        #create entrybox for year
        year = Entry(root,width=5)
        year.grid(column=2,row=2,padx=8)
    
        #create button that runs the find_day command 
        findDay = Button(root,text="Find Weekday",command=lambda:find_day(dy.get(),mon.get(),year.get()),cursor="dot")
        findDay.grid(column=1,row=3)
    
        #Calls the window to open
        root.mainloop()
    
    #so the program only runs when it is called
    if __name__ == "__main__":
        main()

CodePudding user response：

You can create day_of_week label inside main(), pass it to find_day() and update its text inside find_day():

...
def find_day(day_of_week, day, month, year):
    try:
        #cast year as an integer
        year = int(year)
        #turn it into a datetime variable
        date = datetime.date(year, month, day)
        # get the weekday name using Date.strftime()
        day_of_week.config(text=date.strftime('%A'), fg="black")
    except:
        day_of_week.config(text="INVALID DATE", fg="red")

def main():
    ...
    #create button that runs the find_day command
    findDay = Button(root, text="Find Weekday", command=lambda:find_day(day_of_week,dy.get(),mon.get(),year.get()), cursor="dot")
    findDay.grid(column=1, row=3)

    day_of_week = Label(root)
    day_of_week.grid(column=1, row=4)

    #Calls the window to open
    root.mainloop()

...