接收错误：_tkinter.TclError：无效的命令名称“.!frame3.!treeview”

Question

我正在为一家本地企业编写一个简单的程序，该程序将允许其用户轻松跟踪他们的工作服务单。在某一时刻，我让程序正常工作。然而，由于我对编程很陌生，并且输入了很多乱七八糟的代码，所以我回去决定清理一些代码，并添加更好的功能。在这样做的过程中，我导致了一个错误发生，我似乎无法修复它。

我尝试了多种方法来解决这个问题，但我所能确定的是，如果我删除一小段代码，它基本上会按应有的方式运行。

这是两个定义：

def gui_elements_remove(self, elements):
     for element in elements:
        element.destroy()

def Load(self):

    self.gui_elements_remove(self.gui_elements) 
    
    var = self.FirstTree.focus()
    treevar = self.FirstTree.item(var)
    JobDF = pd.DataFrame(treevar, index = [0])
    self.JobID = JobDF.iloc[0]['values']

    cursor1 = self.cursor.execute("SELECT * from 'Service Tickets' WHERE JobID = ?", (self.JobID))
    SP = cursor1.fetchall()
    df = pd.DataFrame(SP, columns = [
                                    'ServiceTicketsID',
                                    'JobID',
                                    'Ticket Number',
                                    'Reason for Visit',
                                    'Warranty/VPO',
                                    'Date Ticket Received',
                                    'Date of Service',
                                    'Service Person'
                                    ])
 


    columns =   [
                'ServiceTicketsID',
                'Ticket Number',
                'Reason for Visit',
                'Warranty/VPO',
                'Date Ticket Received',
                'Date of Service',
                'Service Person'
                ]


    LoadFrame = Frame(self.root)
    LoadFrame.pack(fill = BOTH, expand = True, padx = 50)
    scroll = Scrollbar(LoadFrame, orient = VERTICAL)
    SecondTree = ttk.Treeview(LoadFrame, yscrollcommand = scroll.set, columns = columns)
    SecondTree['show'] = 'headings'
    SecondTree.heading('#1', text = 'ServiceTicketsID')
    SecondTree.heading('#2', text = 'Ticket Number')
    SecondTree.heading('#3', text = 'Reason for Visit')
    SecondTree.heading('#4', text = 'Warranty/VPO')
    SecondTree.heading('#5', text = 'Date Ticket Received')
    SecondTree.heading('#6', text = 'Date of Service')
    SecondTree.heading('#7', text = 'Service Person')
    SecondTree.column('#1', width = 0, stretch = NO)
    SecondTree.column('#2', width = 75, stretch = YES, anchor = "n")
    SecondTree.column('#3', width = 75, stretch = YES, anchor = "n")
    SecondTree.column('#4', width = 75, stretch = YES, anchor = "n")
    SecondTree.column('#5', width = 100, stretch = YES, anchor = "n")
    SecondTree.column('#6', width = 100, stretch = YES, anchor = "n")  
    SecondTree.column('#7', stretch = YES, anchor = "n")   
    scroll.config(command = SecondTree.yview)
    scroll.pack(side = RIGHT, fill = Y)
    SecondTree.pack(fill = BOTH, expand = TRUE)
    Maintree = df   [[
                    'ServiceTicketsID',
                    'Ticket Number',
                    'Reason for Visit',
                    'Warranty/VPO',
                    'Date Ticket Received',
                    'Date of Service',
                    'Service Person'
                    ]]
    Maintree_rows = Maintree.to_numpy().tolist()
    for row in Maintree_rows:
        SecondTree.insert("", 0, values = row)

    for col in columns:
        SecondTree.heading(col, text=col, command=lambda _col=col: \
                    self.Treeview_sort_column(SecondTree, _col, False))

    b1 = Button(LoadFrame, text = "Add")
    b2 = Button(LoadFrame, text = "Update")
    b3 = Button(LoadFrame, text = "Cancel")
    b1.configure(command = lambda: self.Load_Add())
    b2.configure(command = lambda: self.Load_Update())
    #b3.configure(command = lambda: self.Cancel_Button(LoadFile, self.MainWindow, self.root))
    b1.pack(side = LEFT, padx = 5, pady = 50)
    b2.pack(side = LEFT, padx = 5, pady = 50)
    b3.pack(side = LEFT, padx = 5, pady = 50)

还有更多代码，但希望我提供的应该绰绰有余。调用第一个方法以清除上一个正在运行的方法中的帧。其余部分应该从先前的 TreeView 中获取用户的选择。但是，在运行此代码时，我得到了错误

_tkinter.TclError: invalid command name ".!frame3.!treeview"

如果我注释掉这段代码：

        var = self.FirstTree.focus()
    treevar = self.FirstTree.item(var)
    JobDF = pd.DataFrame(treevar, index = [0])
    self.JobID = JobDF.iloc[0]['values']

    cursor1 = self.cursor.execute("SELECT * from 'Service Tickets' WHERE JobID = ?", (self.JobID))
    SP = cursor1.fetchall()
    df = pd.DataFrame(SP, columns = [
                                    'ServiceTicketsID',
                                    'JobID',
                                    'Ticket Number',
                                    'Reason for Visit',
                                    'Warranty/VPO',
                                    'Date Ticket Received',
                                    'Date of Service',
                                    'Service Person'
                                    ])
 

以及与之相关的其余代码，程序运行正常。清除框架并引入新的 TreeView 及其标题。

正如我所说，我是编程新手，因此对使用 StackOverflow 也很陌生。话虽如此，如果我没有提供足够的信息、错误地发布等等，我深表歉意。对于您在代码中可能发现的任何草率，我也提前道歉，哈哈。

感谢所有意见。

Answer 1

JobDF = pd.DataFrame(treevar, index = [0])

和

cursor1 = self.cursor.execute("SELECT * from 'Service Tickets' WHERE JobID = ?", (self.JobID))

是罪魁祸首。

应该是的

JobDF = pd.DataFrame(treevar) #removed the index argument

和

cursor1 = self.cursor.execute("SELECT * from 'Service Tickets' WHERE JobID = ?", (self.JobID,))  #added a comma (self.JobID,))