无法以编程方式将TreeView添加到Box

Question

我正在尝试按钮点击时以编程方式添加TreeView，但没有运气。这是我的例子：

import gi
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk, GLib, Gdk

class TreeView(Gtk.TreeView):

    def __init__(self, items):
        Gtk.TreeView.__init__(self)

        # Creating the ListStore model
        model = Gtk.ListStore(int, str, str)
        for item in items:
            model.append(item)

        # attach model and renderers
        self.set_model(model)
        for i, column_name in enumerate(['c1', 'c2', 'c3']):
            renderer = Gtk.CellRendererText()
            column = Gtk.TreeViewColumn(column_name, renderer, text = i)
            self.append_column(column)

if __name__ == "__main__":
    tv = [
        [ 3, 'AST', 'Practica 1' ],
        [ 5, 'AST', 'Practica 2' ],
        [ 8, 'PBE', 'Practica 3' ]
    ]

    def add(button):
        table = TreeView(tv)
        box.add(table)
        win.show_all()

    win = Gtk.Window()
    win.set_position(Gtk.WindowPosition.CENTER)
    win.set_border_width(10)
    win.set_default_size(600, 400)
    win.connect("destroy", Gtk.main_quit)
    box = Gtk.Box(orientation = Gtk.Orientation.VERTICAL)
    button = Gtk.Button.new_with_label("Add")
    button.connect("clicked", add)
    box.add(button)
    win.add(box)
    win.show_all()
    Gtk.main()

当我单击按钮时，只显示列名，没有数据。如果我在主要内容中table = TreeView(tv)和box.add(table)写得很好。

在ubuntu 16.04上运行。 gtk3版本：3.18.9

编辑：

交换两个TreeView的示例。行为不一致，但适用于ListBox仿真：

import gi
    gi.require_version('Gtk', '3.0')
    from gi.repository import Gtk, GLib, Gdk

def replace_widget(old, new):
    parent = old.get_parent()

    props = {}
    for key in Gtk.ContainerClass.list_child_properties(type(parent)):
        props[key.name] = parent.child_get_property(old, key.name)

    parent.remove(old)
    parent.pack_start(new, False, False, 0)

    for name, value in props.items():
        parent.child_set_property(new, name, value)

    new.show_all()

# native TreeView: doesn't work!
class TreeView(Gtk.TreeView):

    def __init__(self, items, **kwargs):
        # Creating the ListStore model
        model = Gtk.ListStore(*[type(value) for value in items[0].values()])
        for item in items:
            model.append(list(item.values()))

        # Creating the TreeView
        super().__init__(model = model, **kwargs)
        #self.set_model(model)
        self.get_selection().set_mode(Gtk.SelectionMode.NONE) # disable selection
        for i, column_name in enumerate(list(items[0].keys())):
            renderer = Gtk.CellRendererText()
            column = Gtk.TreeViewColumn(column_name, renderer, text = i)
            column.props.expand = True
            self.append_column(column)

'''
# TreeView ListBox emulation: works!
class TreeView(Gtk.ListBox):

    def __init__(self, items, **kwargs):
        super().__init__(**kwargs)

        # header
        row = Gtk.ListBoxRow()
        self.add(row)
        box = Gtk.Box(orientation = Gtk.Orientation.HORIZONTAL, homogeneous = True)
        row.add(box)
        for header in items[0].keys():
            header_label = Gtk.Label(header, halign = Gtk.Align.START)
            box.pack_start(header_label, True, True, 0)

        # data rows
        for i, item in enumerate(items):
            row = Gtk.ListBoxRow()
            self.add(row)
            box = Gtk.Box(orientation = Gtk.Orientation.HORIZONTAL, homogeneous = True)
            row.add(box)
            for column in item.values():
                box.pack_start(Gtk.Label(str(column), halign = Gtk.Align.START), True, True, 0)
'''

if __name__ == "__main__":
    tasks = [
        { 'date': '2018-09-30', 'subject': 'AST', 'name': 'Pràctica 1' },
        { 'date': '2018-10-10', 'subject': 'AST', 'name': 'Pràctica 2' },
        { 'date': '2018-12-05', 'subject': 'AST', 'name': 'Pràctica 3' },
        { 'date': '2018-12-08', 'subject': 'AST', 'name': 'Pràctica 4' },
        { 'date': '2018-10-08', 'subject': 'PBE', 'name': 'Project Plan' },
        { 'date': '2018-10-22', 'subject': 'PBE', 'name': 'Requirement Specifications' },
        { 'date': '2018-11-25', 'subject': 'PBE', 'name': 'Critical Design Report' },
        { 'date': '2018-12-13', 'subject': 'PBE', 'name': 'Final Report' }
    ]

    marks = [
        { 'subject': 'AST', 'name': 'control teoria', 'mark': 7.5, 'student': 'C5CC358A' },
        { 'subject': 'AST', 'name': 'Lab 1', 'mark': 3.5, 'student': 'C5CC358A' },
        { 'subject': 'AST', 'name': 'Lab 2', 'mark': 4.7, 'student': 'C5CC358A' },
        { 'subject': 'AST', 'name': 'final', 'mark': 8.6, 'student': 'C5CC358A' },
        { 'subject': 'PBE', 'name': 'puzzle1', 'mark': 2.8, 'student': 'C5CC358A' },
        { 'subject': 'PBE', 'name': 'puzzle2', 'mark': 8.4, 'student': 'C5CC358A' },
        { 'subject': 'PBE', 'name': 'control', 'mark': 7.3, 'student': 'C5CC358A' },
        { 'subject': 'PBE', 'name': 'CDR', 'mark': 8, 'student': 'C5CC358A' },
        { 'subject': 'PBE', 'name': 'FR', 'mark': 9, 'student': 'C5CC358A' }
    ]

    def clicked(button):
        replace_widget(first, TreeView(marks))

    win = Gtk.Window()
    win.set_position(Gtk.WindowPosition.CENTER)
    win.set_border_width(10)
    win.set_default_size(600, 400)

    win.connect("destroy", Gtk.main_quit)
    box = Gtk.Box(orientation = Gtk.Orientation.VERTICAL)
    button = Gtk.Button.new_with_label("Replace")
    button.connect("clicked", clicked)
    first = TreeView(tasks)
    box.pack_start(first, False, False, 0)
    box.pack_start(button, False, False, 0)
    win.add(box)
    win.show_all()
    Gtk.main()