Python/Kivy：如何在 TreeView 中搜索子节点

Question

我正在使用python-2.7 和kivy-1.9.0。当我运行 test.py 然后显示 name TextInput 。当我输入name 然后TreeView 打开。我为Filter 添加了一个TextInput 文本。但它仅适用于Parent 节点。当我输入R 时，它不会在结果中显示Reserves & Surplus。它不适用于儿童node。
1.有人能告诉我如何在子节点中搜索吗？

test.py

from kivy.uix.screenmanager import Screen
from kivy.app import App
from kivy.lang import Builder
from kivy.core.window import Window
from kivy.uix.popup import Popup
from kivy.uix.treeview import TreeView, TreeViewLabel, TreeViewNode
from kivy.uix.label import Label
from kivy.uix.textinput import TextInput
from kivy.properties import ObjectProperty, ListProperty, StringProperty, NumericProperty
Window.size = (500, 400)


def populate_tree_view(tree_view, parent, node):
    if parent is None:
        tree_node = tree_view.add_node(TreeViewLabel(text=node['node_id'],
                                                     is_open=True))
    else:
        tree_node = tree_view.add_node(TreeViewLabel(text=node['node_id'],
                                                     is_open=True), parent)

    for child_node in node['children']:
        populate_tree_view(tree_view, tree_node, child_node)


class CustomTextInput(TextInput):

    def do_cursor_movement(self, action, control=False, alt=False):
        if not self._lines:
            return
        if action in ('cursor_up', 'cursor_down'):
            App.get_running_app().root.popup._request_keyboard()
        return super(CustomTextInput, self).do_cursor_movement(action, control=control, alt=alt)


class TreeViewLabel(Label, TreeViewNode):
    pass


class TreeViewGroup(Popup):
    tree_view = ObjectProperty(None)
    filter_text_input = ObjectProperty(None)
    tv = ObjectProperty(None)
    filter_text = StringProperty('')
    tree = ListProperty([])
    obj = ObjectProperty(None)

    keycodes = {
        # specials keys
        'backspace': 8, 'tab': 9, 'enter': 13, 'rshift': 303, 'shift': 304,
        'alt': 308, 'rctrl': 306, 'lctrl': 305,
        'super': 309, 'alt-gr': 307, 'compose': 311, 'pipe': 310,
        'capslock': 301, 'escape': 27, 'spacebar': 32, 'pageup': 280,
        'pagedown': 281, 'end': 279, 'home': 278, 'left': 276, 'up':
        273, 'right': 275, 'down': 274, 'insert': 277, 'delete': 127,
        'numlock': 300, 'print': 144, 'screenlock': 145, 'pause': 19,

        # F1-15
        'f1': 282, 'f2': 283, 'f3': 284, 'f4': 285, 'f5': 286, 'f6': 287,
        'f7': 288, 'f8': 289, 'f9': 290, 'f10': 291, 'f11': 292, 'f12': 293,
        'f13': 294, 'f14': 295, 'f15': 296,
    }

    def __init__(self, **kwargs):
        super(TreeViewGroup, self).__init__(**kwargs)
        self._keyboard = None

        self.create_tree_view_root()


        rows = [{'node_id': 'Capital Account',
                 'children': [{'node_id': 'Reserves & Surplus',
                               'children': [{'node_id': '1.1.1',
                                             'children': [{'node_id': '1.1.1.1',
                                                           'children': []}]},
                                            {'node_id': '1.1.2',
                                             'children': []},
                                            {'node_id': '1.1.3',
                                             'children': []}]},
                              {'node_id': '1.2',
                               'children': []}]},
                {'node_id': 'Current Assests',
                 'children': []}]


        self.tree = [{'node_id': r['node_id'], 'children': r['children']} for r in rows]
        self.tv.bind(minimum_height=self.tree_view.setter('height'))
        self.create_tree_view_branch(self.tree)

    def create_tree_view_root(self):
        self.tv = TreeView(root_options=dict(text=""),
                           hide_root=False,
                           indent_level=4)

    def create_tree_view_branch(self, obj):
        for branch in obj:
            populate_tree_view(self.tv, None, branch)
        self.tree_view.add_widget(self.tv)

    def on_open(self, *args):
        self.obj = self.filter_text_input
        self.filter_text_input.focus = True
        self.filter_text = App.get_running_app().root.name.text

    def dismiss_callback(self):
        if self._keyboard is not None:
            self._keyboard.release()
        self.tree_view.clear_widgets()
        self.dismiss()
        App.get_running_app().root.name.focus = True

    def _request_keyboard(self):
        self._keyboard = Window.request_keyboard(self._keyboard_closed, self)
        self._keyboard.bind(on_key_down=self._on_keyboard_down)
        if (self.tv.selected_node is None) \
                and (len(self.tv.root.nodes) > 0):
            self.tv.select_node(self.tv.root.nodes[0])
        else:
            self.filter_text_input.focus = True

    def _keyboard_closed(self):
        self._keyboard.unbind(on_key_down=self._on_keyboard_down)
        self._keyboard.release()
        self._keyboard = None

    def _on_keyboard_down(self, keyboard, keycode, text, modifiers):
        node = self.tv.selected_node
        _, key = keycode
        if key in ('down', 'up'):
            parent = node.parent_node
            ix = parent.nodes.index(node)
            nx = ix+1 if key == 'down' else ix-1
            next_node = parent.nodes[nx % len(parent.nodes)]
            self.tv.select_node(next_node)
            self.scroll.scroll_to(next_node)
        elif key in ('enter', 'numpadenter'):
            App.get_running_app().root.name.text = node.text
            print(node.text)
            self.dismiss_callback()

        # Keycode is composed of an integer + a string
        # If we hit escape, release the keyboard
        if keycode[1] == 'escape':
            keyboard.release()

        if self.string_to_keycode(key) == -1:
            self.filter_text += key
            self.obj.focus = True

        # Return True to accept the key. Otherwise, it will be used by
        # the system.
        return True

    def string_to_keycode(self, value):
        '''Convert a string to a keycode number according to the
        :attr:`TreeViewGroup.keycodes`. If the value is not found in the
        keycodes, it will return -1.
        '''
        return TreeViewGroup.keycodes.get(value, -1)

    def filter(self, value):
        self.tree_view.clear_widgets()
        self.create_tree_view_root()
        filtered_tree = []
        for node in self.tree:
            if value.lower() in node['node_id'].lower():
                filtered_tree.append(node)
        self.create_tree_view_branch(filtered_tree)


class GroupScreen(Screen):
    name = ObjectProperty(None)
    popup = ObjectProperty(None)

    def display_groups(self, instance):
        if len(instance.text) > 0:
            if self.popup is None:
                self.popup = TreeViewGroup()
            self.popup.open()


class Group(App):
    def build(self):
        self.root = Builder.load_file('test.kv')
        return self.root


if __name__ == '__main__':
    Group().run()

test.kv

#:kivy 1.10.0

<CustomTextInput>:
    size_hint_y: .13
    multiline: False

<TreeViewLabel>:
    color_selected: [1, 0, 0, 1]  if self.is_selected else [.1, .1, .1, 1]  # red
    on_touch_down:
        app.root.name.text = self.text
        app.root.popup.dismiss_callback()

<TreeviewGroup>:
    tree_view: tree_view
    filter_text_input: filter_text_input
    title: "Select"
    title_size: 17
    size: 800, 800
    auto_dismiss: False
    scroll: scroll

    BoxLayout
        orientation: "vertical"

        CustomTextInput:
            id: filter_text_input
            text: root.filter_text
            on_text:
                root.filter_text = self.text
                root.filter(self.text)

        ScrollView:
            id: scroll
            size_hint: 1, .9

            BoxLayout:
                size_hint_y: None
                id: tree_view

        GridLayout:
            cols: 2
            row_default_height: '20dp'
            size_hint: .5, 0.1
            pos_hint: {'x': .25, 'y': 1}
            Button:
                text: 'Ok'
                on_release:
                    root.dismiss_callback()

            Button:
                text: 'Cancel'
                on_release:
                    root.dismiss_callback()

<CustomLabel@Label>:
    text_size: self.size
    valign: "middle"
    padding_x: 5

<SingleLineTextInput@TextInput>:
    multiline: False

<GreenButton@Button>:
    background_color: 1, 1, 1, 1
    size_hint_y: None
    height: self.parent.height * 0.150

GroupScreen:
    name: name

    GridLayout:
        cols: 2
        padding : 30,30
        spacing: 10, 10
        row_default_height: '40dp'

        CustomLabel:
            text: ' '

        CustomLabel:
            text: ' '

        CustomLabel:
            text: 'Name'

        SingleLineTextInput:
            id: name
            focus: True
            multiline: False
            on_text: root.display_groups(self)

        GreenButton:
            text: 'Ok'

        GreenButton:
            text: 'Cancel'
            on_press: app.stop()

Answer 1

我从未使用过 kivy，但节点搜索是在 filter 方法中完成的，它不会搜索子节点。因此，将其替换为以下内容：

def filter(self, value):
    self.tree_view.clear_widgets()
    self.create_tree_view_root()
    filtered_tree = []
    v = value.lower() # the lowercase value

    def filter_children(parent): # a recursive inner function
        ch = parent['children']
        if not ch:
            return
        for node in ch:
            if v in node['node_id'].lower():
                filtered_tree.append(node)
            filter_children(node)

    for node in self.tree:
        if v in node['node_id'].lower():
            filtered_tree.append(node)
        filter_children(node) # look into children
    self.create_tree_view_branch(filtered_tree)

如果您粘贴此代码，请注意添加额外的缩进 4。