More Complex TreeView with TreeStore

This TreeView displays a TreeStore with two columns, one of which is rendered as a toggle.

Code used to generate this example

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
from gi.repository import Gtk
from gi.repository import Pango
import sys

books = [["Tolstoy, Leo", ["War and Peace", True], ["Anna Karenina", False]],
         ["Shakespeare, William", ["Hamlet", False],
             ["Macbeth", True], ["Othello", False]],
         ["Tolkien, J.R.R.", ["The Lord of the Rings", False]]]


class MyWindow(Gtk.ApplicationWindow):

    def __init__(self, app):
        Gtk.Window.__init__(self, title="Library", application=app)
        self.set_default_size(250, 100)
        self.set_border_width(10)

        # the data are stored in the model
        # create a treestore with two columns
        self.store = Gtk.TreeStore(str, bool)
        # fill in the model
        for i in range(len(books)):
            # the iter piter is returned when appending the author in the first column
            # and False in the second
            piter = self.store.append(None, [books[i][0], False])
            # append the books and the associated boolean value as children of
            # the author
            j = 1
            while j < len(books[i]):
                self.store.append(piter, books[i][j])
                j += 1

        # the treeview shows the model
        # create a treeview on the model self.store
        view = Gtk.TreeView()
        view.set_model(self.store)

        # the cellrenderer for the first column - text
        renderer_books = Gtk.CellRendererText()
        # the first column is created
        column_books = Gtk.TreeViewColumn("Books", renderer_books, text=0)
        # and it is appended to the treeview
        view.append_column(column_books)

        # the cellrenderer for the second column - boolean rendered as a toggle
        renderer_in_out = Gtk.CellRendererToggle()
        # the second column is created
        column_in_out = Gtk.TreeViewColumn("Out?", renderer_in_out, active=1)
        # and it is appended to the treeview
        view.append_column(column_in_out)
        # connect the cellrenderertoggle with a callback function
        renderer_in_out.connect("toggled", self.on_toggled)

        # add the treeview to the window
        self.add(view)

    # callback function for the signal emitted by the cellrenderertoggle
    def on_toggled(self, widget, path):
        # the boolean value of the selected row
        current_value = self.store[path][1]
        # change the boolean value of the selected row in the model
        self.store[path][1] = not current_value
        # new current value!
        current_value = not current_value
        # if length of the path is 1 (that is, if we are selecting an author)
        if len(path) == 1:
            # get the iter associated with the path
            piter = self.store.get_iter(path)
            # get the iter associated with its first child
            citer = self.store.iter_children(piter)
            # while there are children, change the state of their boolean value
            # to the value of the author
            while citer is not None:
                self.store[citer][1] = current_value
                citer = self.store.iter_next(citer)
        # if the length of the path is not 1 (that is, if we are selecting a
        # book)
        elif len(path) != 1:
            # get the first child of the parent of the book (the first book of
            # the author)
            citer = self.store.get_iter(path)
            piter = self.store.iter_parent(citer)
            citer = self.store.iter_children(piter)
            # check if all the children are selected
            all_selected = True
            while citer is not None:
                if self.store[citer][1] == False:
                    all_selected = False
                    break
                citer = self.store.iter_next(citer)
            # if they do, the author as well is selected; otherwise it is not
            self.store[piter][1] = all_selected


class MyApplication(Gtk.Application):

    def __init__(self):
        Gtk.Application.__init__(self)

    def do_activate(self):
        win = MyWindow(self)
        win.show_all()

    def do_startup(self):
        Gtk.Application.do_startup(self)

app = MyApplication()
exit_status = app.run(sys.argv)
sys.exit(exit_status)

Useful methods for a TreeView widget

The TreeView widget is designed around a Model/View/Controller design: the Model stores the data; the View gets change notifications and displays the content of the model; the Controller, finally, changes the state of the model and notifies the view of these changes. For more information and for a list of useful methods for TreeModel see The Model/View/Controller design.

In line 48 the "toggled" signal is connected to the callback function on_toggled() using widget.connect(signal, callback function). See Signals and callbacks for a more detailed explanation.