Python tkinter不更新布尔值，但更新布尔值表
我无法让tkinter更新一对简单的“应用程序全局”布尔变量以匹配关联复选框的布尔变量。布尔值初始化、更新并存储在一个文件中，并由另一个文件引用（只读）。无论复选框的状态如何，布尔值都不会改变其默认值。（旁注：False/True的初始值变为0/1，可能是由于tkinter推进布尔的方式有问题）。 奇怪的是，与tkinter复选框表对应的类似“应用程序全局”布尔表没有问题。该表是由第三个文件定义的类的实例。该表与简单布尔值位于同一文件中（并以相同的方式处理）。Python tkinter不更新布尔值，但更新布尔值表,python,python-3.x,tkinter,Python,Python 3.x,Tkinter,我无法让tkinter更新一对简单的“应用程序全局”布尔变量以匹配关联复选框的布尔变量。布尔值初始化、更新并存储在一个文件中，并由另一个文件引用（只读）。无论复选框的状态如何，布尔值都不会改变其默认值。（旁注：False/True的初始值变为0/1，可能是由于tkinter推进布尔的方式有问题）。 奇怪的是，与tkinter复选框表对应的类似“应用程序全局”布尔表没有问题。该表是由第三个文件定义的类的实例。该表与简单布尔值位于同一文件中（并以相同的方式处理）。 所有布尔值在一个文件（File1.
所有布尔值在一个文件（File1.py）中使用（只读），并且仅由另一个文件（File2.py）修改。显式返回问题布尔值（从File2.py到File1.py）不起作用 所使用的环境是EclipseJuno上的Windows7、Python 3.2.2（4.2.2，构建M2013024-1200）和Pydev2.7.32013031601插件。应用程序正在从Eclipse控制台运行 根据LEGB范围规则，一切似乎都正常（include和global语句存在，虚线名称形式用于外部定义的“应用程序级别”全局变量）。在我看来，要么所有的布尔更新都能工作，要么一个都不能工作。那么，为什么布尔表可以正常工作，而简单布尔表却不能正常工作？需要什么才能使简单布尔表正常工作？
推测一下，这是否与python将具有基本值（例如0、1、2、3、True？False？）的变量作为“共享值”而不是单独的变量实现的方式有关？这会导致从其他模块引用这些简单值时出现问题 示例应用程序由3个文件组成；每个都已尽可能减少，同时仍能显示问题。在Windows 7上运行时，您应该看到： File1.py-mainline，包含回调函数“获取用户选择”：
from tkinter import *
from tkinter import ttk
import File2
#==========================================================================
def Get_User_Selections( ):
print( "\nDoAllReports=", File2.DoAllReports, "DoNoReports=", File2.DoNoReports )
if ( not File2.DoNoReports ) :
for row in range( len( File2.ChosenReports ) ):
for column in range( len( File2.ChosenReports[ 0 ] ) ) :
if ( File2.ChosenReports[ row ][ column ].get() or
File2.DoAllReports ) :
print( "Do report (", row, ',', column, ')' )
return
#==========================================================================
def CreateTheReports( *args ):
Get_User_Selections( )
return
#==========================================================================
''' *********** MAIN PROCEDURE ***************** '''
root = Tk()
root.title( 'tkinter Boolean problem' )
mainframe = ttk.Frame( root )
mainframe.grid( )
File2.ChooseReports( mainframe )
DoItButton = Button( mainframe, text = 'DO IT!', command = CreateTheReports )
DoItButton.grid()
root.mainloop()
#==========================================================================
from tkinter import *
# import the custom "GUI table" widgit class (which works as expected)
from TkinterCheckBoxTableClass import TkinterCheckBoxTableClass
# Determine the table "shape" (in the original application the strings become
# the row and column headers, these headers NOT shown by this example code).
RowTitles = [ "A", "B" ]
ColumnTitles = [ "1", "2", "3", "4" ]
DefaultReports = [ ]
for i in RowTitles :
for j in ColumnTitles :
DefaultReports = DefaultReports + [ False ]
# Initialize the three "APPLICATION LEVEL" global variables that preserve the
# user choices across invocations of the routine. Each invocation is caused
# by the user pressing the "DO IT!" button on the GUI.
ChosenReports = DefaultReports # table of user choices (works properly)
# These two "application" globals override the table (above) of individual
# choices. "DoNoReports" overrides "DoAllReports"; both override the table.
DoAllReports = False # does not work, value never changes
DoNoReports = False # does not work, value never changes
#==========================================================================
def ChooseReports( ParentFrame ):
# Purpose : Interface between the "application globals" and what appears
# on the GUI. Called from File1.py whenever user presses
# the "DO IT" button
global ChosenReports # "application" global, resides in this file
global DoAllReports # "application" global, resides in this file
global DoNoReports # "application" global, resides in this file
GuiTable = [ [ IntVar() for j in range( len( ColumnTitles ) ) ]
for i in range( len( RowTitles ) ) ]
ThisFrame = LabelFrame( ParentFrame, text = " Select Reports " )
ThisFrame.grid( row = 1, column = 0 )
DoAll = IntVar( value = DoAllReports )
DoNone = IntVar( value = DoNoReports )
SelectAll = Checkbutton( ThisFrame, variable = DoAll, text = "All",
onvalue = True, offvalue = False)
SelectAll.grid( row = 0, column = 1 )
SelectNone = Checkbutton( ThisFrame, variable = DoNone, text ='None',
onvalue = True, offvalue = False )
SelectNone.grid( row = 0, column = 2 )
TableFrame = LabelFrame( ThisFrame, background = 'grey',
borderwidth = 1, relief = FLAT )
TableFrame.grid( row = 1, column = 0, columnspan = 3, rowspan = 2 )
# Create the custom Checkbox Table, works without any problems.
ChooseTheReports = TkinterCheckBoxTableClass( FrameID = TableFrame,
UserSelections = GuiTable )
# Update the "application level" globals
DoAllReports = DoAll.get( )
DoNoReports = DoNone.get( )
ChosenReports = ChooseTheReports.getTable( )
# Passing back the above variables in the return statement did NOT work.
# Returning them shouldn't even be needed since a) they have "application"
# level scope, b) they reside in THIS file and c) are ONLY modified by THIS
# file (with the new values being accessible from other files).
return
#==========================================================================
'''
Implements a 2-D matrix (table) of tkinter checkboxes (for Python 3.x).
'''
from tkinter import *
from tkinter import ttk
class TkinterCheckBoxTableClass( object ):
'''
Python 3.x interface to a matrix (2-D table) of tkinter checkboxes.
Must pass a tkinter frame and the matrix to the constructor.
Class constructor parameters:
FrameID - tkinter parent frame that displays the table
UserSelections - matrix of True/False values passed to/from to GUI
Entire Table Methods:
getTable() - extracts 2-D array of UserSelections from tkinter
'''
'''----------------------------------------------------------------------'''
'''
Constructor
'''
def __init__( self , FrameID, UserSelections ) :
self.frameID = FrameID
self.userSelections = UserSelections
self.rowCount = max( 1, len( self.userSelections ) )
self.columnCount = max( 1, len( self.userSelections[ 0 ] ) )
self.checkBoxTable = [ [ IntVar() for j in range( self.columnCount ) ]
for i in range( self.rowCount ) ]
# Construct and display the table of tkinter checkboxes
for i in range( self.rowCount ) :
for j in range( self.columnCount ) :
self.checkBoxTable[i][j] = Checkbutton( self.frameID,
variable = self.userSelections[ i ][ j ],
onvalue = True, offvalue = False )
self.checkBoxTable[i][j].grid( row = i + 1, column = j + 1,
sticky = W )
'''----------------------------------------------------------------------'''
'''Methods:'''
def getTable( self ) :
for i in range( self.rowCount ) :
for j in range( self.columnCount ) :
self.checkBoxTable[i][j] = Checkbutton( self.frameID,
variable = self.userSelections[ i ][ j ],
onvalue = True,offvalue = False )
self.checkBoxTable[i][j].grid( row = i + 1, column = j + 1,
sticky = W )
return self.userSelections
''' END CLASS '''
from tkinter import *
# import the custom "GUI table" widgit class (which works as expected)
from TkinterCheckBoxTableClass import TkinterCheckBoxTableClass
# Determine the table "shape" (in the original application the strings become
# the row and column headers, these headers NOT shown by this example code).
RowTitles = [ "A", "B" ]
ColumnTitles = [ "1", "2", "3", "4" ]
DefaultReports = [ ]
for i in RowTitles :
for j in ColumnTitles :
DefaultReports = DefaultReports + [ False ]
# Initialize the three "APPLICATION LEVEL" global variables that preserve the
# user choices across invocations of the routine. Each invocation is caused
# by the user pressing the "DO IT!" button on the GUI.
ChosenReports = DefaultReports # table of user choices (works properly)
# These two "application" globals override the table (above) of individual
# choices. "DoNoReports" overrides "DoAllReports"; both override the table.
DoAllReports = False # does not work, value never changes
DoNoReports = False # does not work, value never changes
#==========================================================================
def ChooseReports( ParentFrame ):
# Purpose : Interface between the "application globals" and what appears
# on the GUI. Called from File1.py whenever user presses
# the "DO IT" button
global ChosenReports # "application" global, resides in this file
global DoAllReports # "application" global, resides in this file
global DoNoReports # "application" global, resides in this file
GuiTable = [ [ IntVar() for j in range( len( ColumnTitles ) ) ]
for i in range( len( RowTitles ) ) ]
ThisFrame = LabelFrame( ParentFrame, text = " Select Reports " )
ThisFrame.grid( row = 1, column = 0 )
DoAll = IntVar( value = DoAllReports )
DoNone = IntVar( value = DoNoReports )
SelectAll = Checkbutton( ThisFrame, variable = DoAll, text = "All",
onvalue = True, offvalue = False)
SelectAll.grid( row = 0, column = 1 )
SelectNone = Checkbutton( ThisFrame, variable = DoNone, text ='None',
onvalue = True, offvalue = False )
SelectNone.grid( row = 0, column = 2 )
TableFrame = LabelFrame( ThisFrame, background = 'grey',
borderwidth = 1, relief = FLAT )
TableFrame.grid( row = 1, column = 0, columnspan = 3, rowspan = 2 )
# Create the custom Checkbox Table, works without any problems.
ChooseTheReports = TkinterCheckBoxTableClass( FrameID = TableFrame,
UserSelections = GuiTable )
# Update the "application level" globals
DoAllReports = DoAll.get( )
DoNoReports = DoNone.get( )
ChosenReports = ChooseTheReports.getTable( )
# Passing back the above variables in the return statement did NOT work.
# Returning them shouldn't even be needed since a) they have "application"
# level scope, b) they reside in THIS file and c) are ONLY modified by THIS
# file (with the new values being accessible from other files).
return
#==========================================================================
'''
Implements a 2-D matrix (table) of tkinter checkboxes (for Python 3.x).
'''
from tkinter import *
from tkinter import ttk
class TkinterCheckBoxTableClass( object ):
'''
Python 3.x interface to a matrix (2-D table) of tkinter checkboxes.
Must pass a tkinter frame and the matrix to the constructor.
Class constructor parameters:
FrameID - tkinter parent frame that displays the table
UserSelections - matrix of True/False values passed to/from to GUI
Entire Table Methods:
getTable() - extracts 2-D array of UserSelections from tkinter
'''
'''----------------------------------------------------------------------'''
'''
Constructor
'''
def __init__( self , FrameID, UserSelections ) :
self.frameID = FrameID
self.userSelections = UserSelections
self.rowCount = max( 1, len( self.userSelections ) )
self.columnCount = max( 1, len( self.userSelections[ 0 ] ) )
self.checkBoxTable = [ [ IntVar() for j in range( self.columnCount ) ]
for i in range( self.rowCount ) ]
# Construct and display the table of tkinter checkboxes
for i in range( self.rowCount ) :
for j in range( self.columnCount ) :
self.checkBoxTable[i][j] = Checkbutton( self.frameID,
variable = self.userSelections[ i ][ j ],
onvalue = True, offvalue = False )
self.checkBoxTable[i][j].grid( row = i + 1, column = j + 1,
sticky = W )
'''----------------------------------------------------------------------'''
'''Methods:'''
def getTable( self ) :
for i in range( self.rowCount ) :
for j in range( self.columnCount ) :
self.checkBoxTable[i][j] = Checkbutton( self.frameID,
variable = self.userSelections[ i ][ j ],
onvalue = True,offvalue = False )
self.checkBoxTable[i][j].grid( row = i + 1, column = j + 1,
sticky = W )
return self.userSelections
''' END CLASS '''
顺便说一句，关于PEP8：参见PEP8介绍之后的章节。；>）我也很清楚“应用程序全局”和“创建通用包含文件并到处导入”方法的优缺点；除非绝对没有其他简单的方法来解决我的问题，否则我宁愿不使用它。（我更喜欢只在需要模块的地方导入它们。）似乎只有在创建gui时才设置这些全局变量的值。我看不到任何代码在gui出现并且允许用户与复选按钮交互后更改其值。仅仅因为您使用
DoAll.get（）IntVarDoAll.get（）该表工作的原因是因为它是一个包含
IntVarDoAllReportsdonoreportDoAllReports = IntVar(False)
DoAllReports.get（）DoAllReportsdonoreportIntVarsDoAllDoNoneDoAllReportsdonoreportDoAllReports = DoAll.get()
DoNoReports = DoNone.get()
。。。它们是在用户单击它们所连接的按钮之前，在构建对话框的过程中执行的。因此，您只需返回刚才初始化
IntVarsDO IT，因此它们自然永远不会更新。抽象正是关键所在-它的接口（将价值与获得价值的方式隔离开来）。立即将tkinter值转换为标准类型（例如，从IntVar到int），将转换本地化，并且还消除了在使用该值的所有其他例程中插入.get（）的需要（例如，get_用户选择中的“if”测试）。假设例程是您无法更改的预先存在的代码。对于要使用GUI值的例程，您需要将值传回python布尔值，而不是tkinter“booleanVar”。@user1459519：我想您可能误解了基于事件的编程的工作原理。每当用户单击相关的复选按钮时，IntVar
就会改变。除非添加代码将值复制到全局变量，否则该全局变量将过期。您必须创建代码，以便在每次值更改时更新变量，或者仅在需要时获取值。我个人认为后者更干净，更易于维护。我还认为，您可能不理解调用get（）
的真正价值：它会立即告诉您该值与小部件绑定，这有助于维护。使用全局变量，回答“此变量的值来自何处”的问题变得更加困难。但是，当然，最终你需要使用你最舒服的东西。我只是想确保您理解全局变量与另一个对象保持同步的后果，这正是IntV