tkinter中的可見文本變量輸入小部件

Question

我在使用tkinter中的輸入框小部件時遇到了問題。當用戶選擇Edit - > Backbone ...時，我想要打開一個新窗口。在這個窗口中會出現許多Entry小部件（爲簡單起見，下面只是一個編碼），它們顯示了存儲在各種實例中的默認字符串類Elements。用戶應該能夠編輯這個字符串，並通過點擊OK保存它並通過點擊默認值將它返回到它的默認值。每次主幹編輯器重新打開時，輸入框應始終顯示變量的當前值（如果整個程序重新啓動，則不需要記住用戶輸入）。

在打開'骨架編輯器'窗口時，輸入框應該顯示字符串文本變量，但是我不能讓它出現。

from tkinter import * 
from tkinter import ttk 

class View(ttk.Frame): 
    """Main GUI class""" 

    def __init__(self, master = None): 

     self.WIDTH = 450 
     self.HEIGHT = 500 

     self.lib = MolecularLibrary() 

     # Set up the main window 
     ttk.Frame.__init__(self, master, borderwidth=5, width=self.WIDTH, height=self.WIDTH) 
     self.master.resizable(FALSE, FALSE) 
     self.grid(column=0, row=0, sticky=(N, S, E, W)) 
     self.columnconfigure(0, weight=1) 

     self.create_menus() 

    def create_menus(self): 
     """Produces the menu layout for the main window""" 

     self.master.option_add('*tearOff', FALSE) 

     self.menubar = Menu(self.master) 
     self.master['menu'] = self.menubar 

     # Menu Variables 
     menu_edit = Menu(self.menubar) 

     # Add the menus to the menubar and assign their variables 
     self.menubar.add_cascade(menu=menu_edit, label = "Edit") 

     ### Edit ### 
     menu_edit.add_command(label="Backbone...", command=lambda : self.edit_backbone()) 


    def edit_backbone(self): 
     """Shows a window where the backbone constituents can be edited""" 
     backbone_window = Toplevel(borderwidth = 5) 
     backbone_window.title("Backbone Editor") 
     backbone_window.resizable(FALSE, FALSE) 

     print("sugar value", self.lib.sugar_var) 

     # LABELS FOR BACKBONE # 
     # Phosphate annotations and input 
     sugar_label = ttk.Label(backbone_window, text = "Sugar") 

     #inputs 
     sugar = ttk.Entry(backbone_window, textvariable = self.lib.sugar_var, justify = 'center', width=10) 

     ### Buttons ### 
     default = ttk.Button(backbone_window, text = "Defaults", command=lambda : defaults()) 
     okay = ttk.Button(backbone_window, text = "Okay", command=lambda : okay()) 
     cancel = ttk.Button(backbone_window, text = "Cancel", command=lambda : backbone_window.destroy()) 

     #content.grid(column=0, row=0) 
     sugar_label.grid(column=2, row=1) 
     sugar.grid(column=1, row=2, columnspan=3) 

     default.grid(column=0, row=12, columnspan=3, pady=2) 
     okay.grid(column=6, row=12, columnspan=3, pady=2) 
     cancel.grid(column=9, row=12, columnspan=4, pady=2) 

     backbone_window.focus() 

     def defaults(): 
      """Reset the backbone and bases to their defaults.""" 

      self.lib.set_molecules() 


     def okay(): 
      """Set the backbone and base variables to the user set values.""" 

      self.lib.sugar_var.new_formula(sugar.get()) 

      backbone_window.destroy() 


class MolecularLibrary: 
    """ 
    """ 

    def __init__(self, atom_file = r'C:\MyPyProgs\OSeq\resources\ATOMS.txt', 
       precision = 4): 

     self.molecules = {} 
     self.atom_file = atom_file 
#   self.molecule_file = molecule_file 

     # Variables 
     self.set_molecules() 


    def set_molecules(self): 
     """ 
     Set all of the molecules for the backbone and bases to their default values and forumlae. 
     """ 
       ### Sugar ### 
     self.sugar_var = Element('C5H8O3', 'A') 


    def add_molecule(self, molecule): 
     """(MolecularLibrary, list) -> None 
      Returns a dictionary of the molecule name as an Element 
      {molecule[0]: Element} 
     """ 
     print(molecule) 
     tmp = self.get_mass(molecule[1]) 
     return {molecule[0]: Element(molecule[1], molecule[0], tmp[0], tmp[0])} 

class Element: 
    """ 
    Creates an element with the following construct: 
    [symbol, name, monoisotopic, average] 
    """ 

    def __init__(self, symbol, name): 

     self.symbol = symbol 
     self.name = name 

    def __str__(self): 

     return str([self.symbol, self.name]) 

    def get_name(self): 
     """Returns the name of the Element""" 

     return self.name 

    def get_symbol(self): 
     """Returns the symbol of the Element""" 

     return self.symbol 

    def new_formula(self, new_formula): 
     """replace the formula with new_formaula and recalculate the 
      average and monoisotopic masses.""" 

     self.symbol = new_formula 


if __name__ == "__main__": 
    root = Tk() 
    root.title("Sequencer") 
    view = View(root) 
    root.mainloop() 

上面的代碼是我的程序嚴重剝離版本，但具有相同的基本架構。恐怕還有很多代碼，我通常會試着去掉它，但我不確定我遇到的問題是否來自架構。

Answer 1

爲了使用textvariable屬性，你必須給它一個Tkinter的變量的實例：StringVar，IntVar，BooleanVar，或DoubleVar

一個很好的出發點，詳細瞭解這些變量是在這裏：http://effbot.org/tkinterbook/variable.htm