Question

我正在构建一个桌面应用程序，该应用程序允许您将一些数据插入表单，然后以一系列（3）Treeview小部件显示数据。这是我用来输入新数据的表格：

它在顶级小部件中。当按下添加按钮时，新数据将存储在文件中，并且还应将新数据插入相应的Treeview小部件中。这是根窗口：

它由3个Treeview小部件组成。该应用程序的目的是使用户有机会将候选者分类到正确的Treeview小部件中。我面临的问题是，当按下添加按钮时，新数据不会显示在Treeview小部件中，并且不会给出任何错误。我认为这可能是类实例化的问题。 这是我的应用摘录，请在下面查看最小，完整和可验证的示例

class MainApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        ...
        # frame and menu classes are instantiated here
        self.FrameList = {ViableCandidates: ViableCandidates(self),
                          NotViableCandidates: NotViableCandidates(self),
                          InProgressCandidates: InProgressCandidates(self)}
        ...
    def InstanceLinker(self, frame):
        link = self.FrameList[frame]
        return link
class GUIMenu(tk.Menu):
    def __init__(self, parent):
        ...
    # menu code is here
    addcandidates.add_command(label='Quick Add', command=lambda: QuickAdd(parent))
class QuickAdd(tk.Toplevel):
    def __init__(self, parent):
        ...
    # code for the small Toplevel window
    ...
    # this is the code that I use to add the new item to Treeview when the Add button is pressed
    if CandidateInfo['status'] == 'Viable':
        app.InstanceLinker(ViableCandidates).AddtoList()
    elif CandidateInfo['status'] == 'Not Viable':
        app.InstanceLinker(NotViableCandidates).AddtoList()
    else:
        app.InstanceLinker(InProgressCandidates).AddtoList()
# ViableCandidates, NotViableCandidates, InProgressCandidates are created with the same pattern
class InProgressCandidates(tk.Frame):
    def __init__(self, parent):
        global Counter
        tk.Frame.__init__(self, parent)
        self.columnconfigure(0, weight=1)
        self.rowconfigure(1, weight=1)
        title = tk.Label(self, text="Candidates In Progress", font="Verdana 10 bold")
        title.grid(row=0, column=0, sticky='nesw')
        self.tree = ttk.Treeview(self)
        self.tree.grid(row=1, column=0, sticky='nesw')
        scrollbar = ttk.Scrollbar(self, orient='vertical', command=self.tree.yview)
        scrollbar.grid(row=1, column=1, sticky='nws')
        self.tree.config(columns=('Name', 'Date'), selectmode='browse', height=20, yscrollcommand=scrollbar.set)
        self.tree.column('#0', width=20, minwidth=10, stretch=tk.YES)
        self.tree.column('Name', width=150, minwidth=10, stretch=tk.YES)
        self.tree.column('Date', width=80, minwidth=10, stretch=tk.YES)
        self.tree.heading('#0', text='#', anchor=tk.W)
        self.tree.heading('Name', text='Name', anchor=tk.W)
        self.tree.heading('Date', text='Date', anchor=tk.W)
        if Counter < 4:
            Counter += 1
            self.PopulateList()
    def PopulateList(self):
        selection = Database().SelectFromDB('name, date', "status = 'In progress'")
        for i in range(len(selection)):
            name = list(selection[i])[0]
            date = adjusttotimezone(list(selection[i])[1])
            self.tree.insert("", i, name, text=i + 1)
            self.tree.set(name, 'Name', name)
            self.tree.set(name, 'Date', date)
            CandidateCounter['InProgressCandidates'] = i
    def AddtoList(self):
        CandidateCounter['InProgressCandidates'] += 1
        print('I was here')
        self.tree.insert("", CandidateCounter['InProgressCandidates'], CandidateInfo['name'],
                         text=CandidateCounter['InProgressCandidates'])
        self.tree.set(CandidateInfo['name'], 'Name', CandidateInfo['name'])
        selection = Database().SelectFromDB('date', "name = '" + CandidateInfo['name'] + "'")
        date = adjusttotimezone(list(selection[0])[0])
        self.tree.set(CandidateInfo['name'], 'Date', date)
app = MainApp()
app.mainloop()

当按下“添加”按钮时，没有错误，并且打印了“我在这里”，因此实例化了AddtoList方法，但是没有新项目添加到Treeview中。我确实检查了用于创建新Treeview项的变量是否包含正确的数据，并且确实如此。

编辑：这是一个最小，完整和可验证的示例：

import tkinter as tk
from tkinter import ttk
Bigbadtext = ''
Counter = 0
class MainApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        self.MainWindow = tk.Tk.__init__(self, *args, **kwargs)
        menu = GUIMenu(self)
        self.config(menu=menu)
        frame = InProgressCandidates(self)
        frame.grid(row=0, column=1, sticky='nesw')
        self.FrameList = {InProgressCandidates:InProgressCandidates(self)}
    def InstanceLinker(self, frame):
        link = self.FrameList[frame]
        return link
class GUIMenu(tk.Menu):
    def __init__(self, parent):
        tk.Menu.__init__(self, parent)
        addcandidates = tk.Menu(self, tearoff=0)
        self.add_cascade(label='Add Candidates', menu=addcandidates)
        addcandidates.add_command(label='Quick Add', command=lambda: QuickAdd(parent))
class QuickAdd(tk.Toplevel):
    def __init__(self, parent):
        tk.Toplevel.__init__(self, parent)
        saysomething = tk.Entry(self)
        saysomething.grid(row=1, column=0)
        def addbutton():
            global Bigbadtext
            Bigbadtext = saysomething.get()
            app.InstanceLinker(InProgressCandidates).AddtoList()
        okbutton = ttk.Button(self, text='Add', command=addbutton)
        okbutton.grid(row=2, column=0)
class InProgressCandidates(tk.Frame):
    def __init__(self, parent):
        tk.Frame.__init__(self, parent)
        self.tree = ttk.Treeview(self)
        self.tree.grid(row=1, column=0, sticky='nesw')
        scrollbar = ttk.Scrollbar(self, orient='vertical', command=self.tree.yview)
        scrollbar.grid(row=1, column=1, sticky='nws')
        self.tree.config(columns='something', selectmode='browse', height=20, yscrollcommand=scrollbar.set)
        self.tree.column('#0', width=20, minwidth=10, stretch=tk.YES)
        self.tree.column('something', width=150, minwidth=10, stretch=tk.YES)
        self.tree.heading('#0', text='#', anchor=tk.W)
        self.tree.heading('something', text='Say something', anchor=tk.W)
    def AddtoList(self):
        global Counter
        Counter += 1
        print('I was here')
        self.tree.insert("", Counter, Bigbadtext, text=Counter)
        self.tree.set(Bigbadtext, 'something', Bigbadtext)
app = MainApp()
app.mainloop()

Answer 1

问题是您要创建两个树形视图小部件，然后将项目添加到不可见的一个。

您在此处创建一个：

frame = InProgressCandidates(self)

然后您在此处创建另一个：

self.FrameList = {InProgressCandidates:InProgressCandidates(self)}

由于您已经创建了一个，所以您创建的那个应该是self.FrameList中的内容：

self.FrameList = {InProgressCandidates:frame}

Answer 2

这不是真正的答案，但我对这个问题投了赞成票，因为它解决了我的问题。我想向小部件添加项目，但不想在完成填充树之前将其显示给用户。但是每个插入都立即显示出来。现在我创建了 2 个相同的小部件，一个可见，另一个不可见，一旦填充，我就会在它们之间进行更改。因此，即使是错误也会有好处。

Tkinter Treeview不显示新插入的项目，未给出错误

2 个答案: