如何在Kivy中从数据库中获取数据

Question

test.py

import sqlite3 as lite

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.properties import ObjectProperty


Window.size = (700, 530)

con = lite.connect('demo.db')
con.text_factory = str
cur = con.cursor()


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)


tree = [{'node_id': 'Test2',
         'children': []},
        {'node_id': 'Test3',
         'children': []}]


class TreeViewLabel(Label, TreeViewNode):
    pass


class TreeviewGroup(Popup):
    treeview = ObjectProperty(None)
    tv = ObjectProperty(None)

    def __init__(self, **kwargs):
        super(TreeviewGroup, self).__init__(**kwargs)
        self.tv = TreeView(root_options=dict(text="Test1"),
                           hide_root=False,
                           indent_level=4)
        for branch in tree:
            populate_tree_view(self.tv, None, branch)
        self.remove_widgets()
        self.treeview.add_widget(self.tv)

    def remove_widgets(self):
        for child in [child for child in self.treeview.children]:
            self.treeview.remove_widget(child)


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

    def display_groups(self, instance):
        if len(instance.text) > 0:
            self.popup = TreeviewGroup()
            self.popup.open()


class Group(App):
    #cur.execute("SELECT * FROM `m_state` order by state_id asc")
    #rows = cur.fetchall()
    #print(rows)
    rows = [(1, 'test1', 111), (2, 'test2', 112), (3, 'test3', 113), (4, 'test4', 114)]
    def build(self):
        self.root = Builder.load_file('test.kv')
        return self.root


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

test.kv

：kivy 1.10.0

<TreeViewLabel>:
    on_touch_down:
        app.root.stateName.text = self.text
        app.root.popup.dismiss()

<TreeviewGroup>:
    id: treeview
    treeview: treeview
    title: "Select City"
    size_hint: None, None
    size: 400, 400
    auto_dismiss: False

    BoxLayout
        orientation: "vertical"
        BoxLayout:
            id: treeview
        Button:
            size_hint: 1, 0.1
            text: "Close"
            on_release: root.dismiss()


<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:
    stateName: stateName

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

        CustomLabel:
            text: 'State Name'

        SingleLineTextInput:
            id: stateName
            on_text: root.display_groups(self)

        CustomLabel:
            text: 'State Code'

        Spinner:
            text: "State Code"
            values: ["111", "112", "113", "114"]
            #background_color: color_button if self.state == 'normal' else color_button_pressed
            background_down: 'atlas://data/images/defaulttheme/spinner'
            #color: color_font
            #option_cls: Factory.get("MySpinnerOption")
            #size_hint: None, None


        CustomLabel:
            text: 'City Name'

        SingleLineTextInput:
            id: cityName

        CustomLabel:
            text: 'Short Name'

        SingleLineTextInput:
            id: shortName

        CustomLabel:
            text: 'Pin Code'

        SingleLineTextInput:
            id: pinCode

        GreenButton:
            text: 'Ok'

        GreenButton:
            text: 'Cancel'

        Label:

        Label:

有人可以帮助我吗？  1.在上面的图像状态代码显示111,112,113,114是静态的。如何显示动态这些状态代码。我从数据库中检索数据看起来如何  rows = [（1，'test1'，111），（2，'test2'，112），（3，'test3'，113），（4，'test4'，114）]

第三个指数值即将到来111,112,113,114。如何将这些值放在微调器中。

Answer 1

您可以在组类中设置listproperty属性，然后在kv中使用此列表设置微调器的值：

.py ：

中的

...

class Group(App):
    #cur.execute("SELECT * FROM `m_state` order by state_id asc")
    #rows = cur.fetchall()
    #print(rows)
    rows = [(1, 'test1', 111), (2, 'test2', 112), (3, 'test3', 113), (4, 'test4', 114)]
    r = ListProperty()
    r = [str(t[2]) for t in rows]

...

然后在 .kv ：

...

Spinner:
    text: "State Code"
    values: app.r

...

我使用了Lisproperty，以防将来价值发生变化