TypeError: 'DoubleVar' -Objekt kann nicht implizit in str konvertiert werden

Question

Ich erstelle ein einfaches GUI-Programm, um die Zeit von einem bestimmten Ereignis zu messen. Ich erhalte eine Fehlermeldung:

/usr/bin/python3.5 /home/cali/PycharmProjects/str8/str8.py Traceback (most recent call last): File "/home/cali/PycharmProjects/str8/str8.py", line 51, in app = App(root) File "/home/cali/PycharmProjects/str8/str8.py", line 22, in init Label(self, text=measurement + ": " + self.counters[measurement], font='Verdana 8').grid(row=i+1, column=0, sticky=W) TypeError: Can't convert 'DoubleVar' object to str implicitly

Process finished with exit code 1

ich das versucht:

Label(self, text=measurement + ": " + str(self.counters[measurement]), font='Verdana 8').grid(row=i+1, column=0, sticky=W) 

... aber es gibt mir dies:

GUI program

Hier ist, was ich getan habe:

# str8.py 
# Program to count time from a certain event 

from tkinter import * 
from datetime import * 


class App(Frame): 

    def __init__(self, *args, **kwargs): 

     Frame.__init__(self, *args, **kwargs) 
     self.grid(sticky = N + W + E + S) 

     Label(self, text = 'You have been STR8 for:', font="Verdana 8 bold").grid(row=0, sticky=W) 

     self.counters = dict() 
     measurements = [ 'Years', 'Weeks', 'Days', 'Hours', 'Minutes', 'Seconds' ] 

     for i, measurement in enumerate(measurements): 
      self.counters[measurement] = DoubleVar() 
      Label(self, text=measurement + ": " + self.counters[measurement], font='Verdana 8').grid(row=i+1, column=0, sticky=W) 
      self.counters[measurement].set(0) 

     Button(self, 
       text="EXIT", 
       font="Verdana 8", 
       height=1, 
       width=19, 
       command=quit).grid(row=7, column=0) 

     self.increment() 

    def increment(self): 
     event = datetime(2017, 4, 4, 0, 0, 0) 
     today = datetime.now() 

     str8 = today - event 
     self.counters['Seconds'].set(round(str8.total_seconds(), 2)) 
     self.counters['Minutes'].set(round(str8.total_seconds()/ 60, 2)) 
     self.counters['Hours'].set(round(str8.total_seconds()/3600, 2)) 
     self.counters['Days'].set(round(str8.total_seconds()/(3600 * 24), 2)) 
     self.counters['Weeks'].set(round(str8.total_seconds()/(3600 * 24 * 7), 2)) 
     self.counters['Years'].set(round(str8.total_seconds()/(3600 * 24 * 7 * 52), 2)) 

     self.after(1000, self.increment) 


if __name__ == '__main__': 
    root = Tk() 
    app = App(root) 
    root.title("STR8") 
    root.resizable(width=False, height=False) 
    app.mainloop() 

Answer 1

Ein Label kann einen Text mit dem Argument text anzeigen ODER den Wert einer tkinter-Variablen wie eine DoubleVar mit dem Argument textvariable anzeigen. Es kann nicht beides. Entweder verwenden Sie diese:

lbl = Label(self, text=measurement + ": ", font='Verdana 8') 
lbl.grid(row=i+1, column=0, sticky=W) 

Oder diese:

lbl = Label(self, textvariable=self.counters[measurement], font='Verdana 8') 
lbl.grid(row=i+1, column=0, sticky=W) 

Edit: Eine Lösung für Ihr Problem wäre es, Ihre eigene Art von Label zu machen, die sowohl handhaben kann:

import tkinter as tk 
from datetime import datetime 

class FormatLabel(tk.Label): 
    '''A new type of Label widget that allows both a text and textvariable''' 
    def __init__(self, master=None, **kwargs): 
     self.textvariable = kwargs.pop('textvariable', tk.StringVar(master)) 
     self.text = kwargs.pop('text', '{}') 
     self.textvariable.trace('w', self.update_text) 
     tk.Label.__init__(self, master, **kwargs) 

    def update_text(self, *args): 
     self.config(text=self.text.format(self.textvariable.get())) 

class App(tk.Frame): 
    def __init__(self, master=None, **kwargs): 
     tk.Frame.__init__(self, master, **kwargs) 

     lbl = tk.Label(self, text = 'You have been STR8 for:', font="Verdana 8 bold") 
     lbl.grid(row=0, sticky=tk.W) 

     self.counters = dict() 
     measurements = [ 'Years', 'Weeks', 'Days', 'Hours', 'Minutes', 'Seconds' ] 

     for i, measurement in enumerate(measurements): 
      self.counters[measurement] = tk.DoubleVar() 
      lbl = FormatLabel(self, 
       text=measurement + ": {:.2f}", # set the rounding here 
       textvariable = self.counters[measurement], 
       font='Verdana 8') 
      lbl.grid(row=i+1, column=0, sticky=tk.W) 
      self.counters[measurement].set(0) 

     btn = tk.Button(self, 
       text="EXIT", 
       font="Verdana 8", 
       height=1, 
       width=19, 
       command=quit) 
     btn.grid(row=7, column=0) 

     self.increment() 

    def increment(self): 
     event = datetime(2017, 4, 4, 0, 0, 0) 
     today = datetime.now() 

     str8 = (today - event).total_seconds() 
     self.counters['Seconds'].set(str8) 
     self.counters['Minutes'].set(str8/60.) 
     self.counters['Hours'].set(str8/3600.) 
     self.counters['Days'].set(str8/(3600. * 24)) 
     self.counters['Weeks'].set(str8/(3600. * 24 * 7)) 
     self.counters['Years'].set(str8/(3600. * 24 * 7 * 52)) 

     self.after(1000, self.increment) 

def main(): 
    root = tk.Tk() 
    app = App(root) 
    app.pack() 
    root.title("STR8") 
    root.resizable(width=False, height=False) 
    app.mainloop() 

if __name__ == '__main__': 
    main() 

Hinweis Ich habe auch einige andere Teile deines Codes repariert. Vor allem, dass Sie keine Platzhalterimporte verwenden sollten (from module import *), sollten Sie Widgets nicht in derselben Zeile wie Sie sie definieren, und Sie sollten versuchen, den Code nicht zu wiederholen.