当我单击行时，它显示错误 IndexError: list index out of range

Question

menu.py

import kivy

kivy.require('1.9.0')  # replace with your current kivy version !
import sqlite3 as lite
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import BooleanProperty, ListProperty, StringProperty, ObjectProperty,NumericProperty
from kivy.lang import Builder
from kivy.uix.dropdown import DropDown

from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.button import Button
from kivy.uix.recyclegridlayout import RecycleGridLayout
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
from kivy.uix.popup import Popup
from kivy.core.window import Window
import sys
#Window.borderless = True

#Window.clearcolor = (0, 0.517, 0.705, 1)

Window.size = (900, 500)
#from easygui import msgbox

#db =lite.connect(':memory:')
con = lite.connect('test.db')
con.text_factory = str
cur = con.cursor()


class EditStatePopup(Popup):
    obj = ObjectProperty(None)
    start_point = NumericProperty(0)
    max_table_cols = NumericProperty(0)
    new_data = ListProperty([])
    stateId = StringProperty("")
    stateName = StringProperty("")
    stateCode = StringProperty("")

    def __init__(self, obj, **kwargs):
        super(EditStatePopup, self).__init__(**kwargs)
        self.obj = obj
        self.start_point = obj.start_point
        self.max_table_cols = obj.max_table_cols
        self.stateId = obj.rv_data[obj.start_point]["text"]
        self.stateName = obj.rv_data[obj.start_point + 1]["text"]
        self.stateCode = obj.rv_data[obj.start_point + 2]["text"]

    def package_changes(self, stateId, stateName, stateCode):
        print(stateName)
        self.new_data.append(stateId)
        self.new_data.append(stateName)
        self.new_data.append(stateCode)


class SelectableRecycleGridLayout(FocusBehavior, LayoutSelectionBehavior,
                                  RecycleGridLayout):
    ''' Adds selection and focus behaviour to the view. '''


class SelectableButton(RecycleDataViewBehavior, Button):
    ''' Add selection support to the Button '''
    index = None
    selected = BooleanProperty(False)
    selectable = BooleanProperty(True)
    rv_data = ObjectProperty(None)
    start_point = NumericProperty(0)
    max_table_cols = NumericProperty(3)
    data_items = ListProperty([])

    def refresh_view_attrs(self, rv, index, data):
        ''' Catch and handle the view changes '''
        self.index = index
        return super(SelectableButton, self).refresh_view_attrs(rv, index, data)

    def on_touch_down(self, touch):
        ''' Add selection on touch down '''
        if super(SelectableButton, self).on_touch_down(touch):
            return True
        if self.collide_point(*touch.pos) and self.selectable:
            return self.parent.select_with_touch(self.index, touch)

    def apply_selection(self, rv, index, is_selected):
        ''' Respond to the selection of items in the view. '''
        self.selected = is_selected
        self.rv_data = rv.data
        #print("selection changed to {0}".format(rv.data[1]))


    def on_press(self):
        end_point = self.max_table_cols
        rows = len(self.rv_data) # self.max_table_cols
        #print(end_point) // 3
        #print(rows) // 3
        for row in range(rows):
            cols = list(range(end_point))
            #print(cols) // [0, 1, 2]
            #print(self.index) //1
            #print(self.max_table_cols)//3
            if self.index in cols:
                break
            self.start_point += self.max_table_cols
            end_point += self.max_table_cols

        popup = EditStatePopup(self)
        popup.open()

    def update_states(self, stateId, stateName, stateCode):

        cur.execute("UPDATE m_state SET state_name=?, state_code=? WHERE state_id=?",(stateName, stateCode, stateId))
        con.commit()

class RV(BoxLayout):
    data_items = ListProperty([])

    def __init__(self, **kwargs):
        super(RV, self).__init__(**kwargs)
        self.get_states()

    def get_states(self):

        cur.execute("SELECT * FROM `m_state` order by state_id asc")
        rows = cur.fetchall()

        #print(rows)
        # create data_items
        rows = [(1, 'Test', '01'), (2, 'test2', '02'), (2, 'test2', '03')]
        for row in rows:
            for col in row:
                self.data_items.append(col)
                #print(col)

class CustDrop(DropDown):
    def __init__(self, **kwargs):
        super(CustDrop, self).__init__(**kwargs)
        self.select('')

class MainMenu(BoxLayout):
    states = ObjectProperty(None)
    dropdown = ObjectProperty(None)

    def display_states(self):
        # rv = RV()
        self.dropdown.dismiss()
        self.states.add_widget(RV())
        #return CustDrop()

class FactApp(App):
    title = "Test"

    def build(self):
        self.root = Builder.load_file('m_ListState.kv')
        return MainMenu()



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

m_ListState.kv

#:kivy 1.10.0
#:import CoreImage kivy.core.image.Image
#:import os os

<EditStatePopup>:
    title: "Update State"
    size_hint: None, None
    size: 300, 300
    auto_dismiss: False

    BoxLayout:
        orientation: "vertical"
        GridLayout:
            cols: 2
            Label:
                text: "Id"
            Label:
                id: stateId
                text: root.stateId
            Label:
                text: "Name"
            TextInput:
                id: stateName
                text: root.stateName
            Label:
                text: "Code"
            TextInput:
                id: stateCode
                text: root.stateCode

            Button:
                size_hint: 1, 0.4
                text: "Cancel"
                on_release: root.dismiss()

            Button:
                size_hint: 1, 0.4
                text: "Ok"
                on_release:
                    root.package_changes(stateId.text, stateName.text, stateCode.text)
                    #root.obj.update_states(root.start_point, root.max_table_cols, root.new_data)
                    root.obj.update_states(stateId.text, stateName.text, stateCode.text)
                    root.dismiss()



<SelectableButton>:
    # Draw a background to indicate selection
    canvas.before:
        Color:
            rgba: (.0, 0.9, .1, .3) if self.selected else (0, 0, 0, 1)
        Rectangle:
            pos: self.pos
            size: self.size

<RV>:
    BoxLayout:
        orientation: "vertical"

        GridLayout:
            size_hint: 1, None
            size_hint_y: None
            height: 25
            cols: 3

            Label:
                text: "Id"
            Label:
                text: "Name"
            Label:
                text: "Code"

        BoxLayout:
            RecycleView:
                viewclass: 'SelectableButton'
                data: [{'text': str(x)} for x in root.data_items]
                SelectableRecycleGridLayout:
                    cols: 3
                    default_size: None, dp(26)
                    default_size_hint: 1, None
                    size_hint_y: None
                    height: self.minimum_height
                    orientation: 'vertical'
                    multiselect: True
                    touch_multiselect: True



<DropdownButton@Button>:
    border: (0, 16, 0, 16)
    text_size: self.size
    valign: "middle"
    padding_x: 5
    size_hint_y: None
    height: '30dp'
    background_color: 90 , 90, 90, 90
    color: 0, 0.517, 0.705, 1



<MenuButton@Button>:
    text_size: self.size
    valign: "middle"
    padding_x: 5
    size : (80,30)
    size_hint : (None, None)
    background_color: 90 , 90, 90, 90
    background_normal: ''
    color: 0, 0.517, 0.705, 1
    border: (0, 10, 0, 0)


<MainMenu>:
    states: states
    dropdown: dropdown

    BoxLayout:
        orientation: 'vertical'
        #spacing : 10

        BoxLayout:
            canvas.before:
                Rectangle:
                    pos: self.pos
                    size: self.size

            size_hint_y: 1

            MenuButton:
                id: btn
                text: 'View'
                size : (60,30)
                on_release: dropdown.open(self)

            CustDrop:
                id: dropdown
                auto_width: False
                width: 150

                DropdownButton:
                    text: 'State'
                    size_hint_y: None
                    height: '32dp'
                    #on_release: dropdown3.open(self)
                    on_release: root.display_states()

                DropdownButton:
                    text: 'City'
                    size_hint_y: None
                    height: '32dp'
                    #on_release: dropdown3.open(self)
                    on_release: root.display_city()

        BoxLayout:
            canvas.before:
                Rectangle:
                    pos: self.pos
                    size: self.size

                Color:
                    rgb: (1,1,1)

            AsyncImage:
                source: "add.jpg"
                #on_release: os.system("python m_State.py")

            Label:
                size_hint_x: 22

        BoxLayout:
            id: states
            size_hint_y: 9

        Label:
            size_hint_y: 9

谁能帮忙解决一些问题？？
1.当我一次又一次单击状态（视图子菜单）时，数据重复。如何避免它。当我单击状态时，应显示状态列表，当我单击城市时，应显示城市列表。display_city（ ）我还没有写这个只是为了举例。
2. 当我点击取消两次然后它显示错误 IndexError: list index out of range.
3.当我更新状态时，它会在数据库中更新，但不会在屏幕上实时更改。如果我再次运行，则会显示更新的数据。

Answer 1

请参考问题、解决方案和示例来解决您的问题。

重复的列

问题

每次单击查看时，都会动态添加小部件。如果您单击两次查看，列会重复两次。

解决方案

您必须在每次动态添加小部件之前删除它们。

def display_states(self):
    self.dropdown.dismiss()
    self.remove_widgets()
    self.rv = RV()
    self.states.add_widget(self.rv)

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

索引错误

问题

每当您单击每一行数据时，它都会调用 on_press 方法。 self.start_point 在类 SelectableButton 实例化时初始化。

解决方案

在on_press方法中初始化self.start_point。

def on_press(self):
    self.start_point = 0
    end_point = MAX_TABLE_COLS
    rows = len(self.rv_data) // MAX_TABLE_COLS

    for row in range(rows):
        if self.index in list(range(end_point)):
            break
        self.start_point += MAX_TABLE_COLS
        end_point += MAX_TABLE_COLS

    popup = EditStatePopup(self)
    popup.open()

RecycleView 未更新

问题

在update_states方法中，缺少RecycleView的数据更新。

解决方案

添加以下内容以更新 RecycleView 的数据。

def update_states(self, obj):
    # update data_items
    # obj.start_point + 1 --- skip State_ID
    for index in range(obj.start_point + 1, obj.start_point + MAX_TABLE_COLS):
        self.rv.data_items[index] = obj.col_data[index - obj.start_point]

    # update Database Table
    cur.execute("UPDATE m_state SET State_Name=?, State_Code=? WHERE State_ID=?",
                (obj.col_data[1], obj.col_data[2], obj.col_data[0]))
    con.commit()

示例

m_ListState.py

​​>

import kivy
kivy.require('1.10.0')  # replace with your current kivy version !

import sqlite3 as lite
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import BooleanProperty, ListProperty, ObjectProperty,NumericProperty
from kivy.lang import Builder
from kivy.uix.dropdown import DropDown

from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.button import Button
from kivy.uix.recyclegridlayout import RecycleGridLayout
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
from kivy.uix.popup import Popup
from kivy.core.window import Window

import sys
#Window.borderless = True

#Window.clearcolor = (0, 0.517, 0.705, 1)

Window.size = (900, 500)
#from easygui import msgbox

MAX_TABLE_COLS = 3

path = "/home/iam/dev/SQLite/sampleDB/StateCodesNamesDB/"

#db =lite.connect(':memory:')
# con = lite.connect('fact.db')
con = lite.connect(path + 'country.db')
con.text_factory = str
cur = con.cursor()


class EditStatePopup(Popup):
    start_point = NumericProperty(0)
    col_data = ListProperty(["?", "?", "?"])

    def __init__(self, obj, **kwargs):
        super(EditStatePopup, self).__init__(**kwargs)
        self.start_point = obj.start_point
        self.col_data[0] = obj.rv_data[obj.start_point]["text"]
        self.col_data[1] = obj.rv_data[obj.start_point + 1]["text"]
        self.col_data[2] = obj.rv_data[obj.start_point + 2]["text"]

    def package_changes(self, stateName, stateCode):
        self.col_data[1] = stateName
        self.col_data[2] = stateCode


class SelectableRecycleGridLayout(FocusBehavior, LayoutSelectionBehavior,
                                  RecycleGridLayout):
    ''' Adds selection and focus behaviour to the view. '''


class SelectableButton(RecycleDataViewBehavior, Button):
    ''' Add selection support to the Button '''
    index = None
    selected = BooleanProperty(False)
    selectable = BooleanProperty(True)
    rv_data = ObjectProperty(None)
    start_point = NumericProperty(0)

    def refresh_view_attrs(self, rv, index, data):
        ''' Catch and handle the view changes '''
        self.index = index
        return super(SelectableButton, self).refresh_view_attrs(rv, index, data)

    def on_touch_down(self, touch):
        ''' Add selection on touch down '''
        if super(SelectableButton, self).on_touch_down(touch):
            return True
        if self.collide_point(*touch.pos) and self.selectable:
            return self.parent.select_with_touch(self.index, touch)

    def apply_selection(self, rv, index, is_selected):
        ''' Respond to the selection of items in the view. '''
        self.selected = is_selected
        self.rv_data = rv.data

    def on_press(self):
        self.start_point = 0
        end_point = MAX_TABLE_COLS
        rows = len(self.rv_data) // MAX_TABLE_COLS

        for row in range(rows):
            if self.index in list(range(end_point)):
                break
            self.start_point += MAX_TABLE_COLS
            end_point += MAX_TABLE_COLS

        popup = EditStatePopup(self)
        popup.open()


class RV(BoxLayout):
    data_items = ListProperty([])

    def __init__(self, **kwargs):
        super(RV, self).__init__(**kwargs)
        self.get_states()

    def get_states(self):
        cur.execute("SELECT * FROM m_state order by State_ID asc")
        rows = cur.fetchall()

        # create data_items
        for row in rows:
            for col in row:
                self.data_items.append(col)


class CustDrop(DropDown):
    def __init__(self, **kwargs):
        super(CustDrop, self).__init__(**kwargs)
        self.select('')


class MainMenu(BoxLayout):
    rv = ObjectProperty(None)
    states = ObjectProperty(None)
    dropdown = ObjectProperty(None)

    def display_states(self):
        self.dropdown.dismiss()
        self.remove_widgets()
        self.rv = RV()
        self.states.add_widget(self.rv)

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

    def update_states(self, obj):
        # update data_items
        # obj.start_point + 1 --- skip State_ID
        for index in range(obj.start_point + 1, obj.start_point + MAX_TABLE_COLS):
            self.rv.data_items[index] = obj.col_data[index - obj.start_point]

        # update Database Table
        cur.execute("UPDATE m_state SET State_Name=?, State_Code=? WHERE State_ID=?",
                    (obj.col_data[1], obj.col_data[2], obj.col_data[0]))
        con.commit()


class FactApp(App):
    title = "Test"

    def build(self):
        self.root = Builder.load_file('m_ListState.kv')
        return MainMenu()


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

m_ListState.kv

#:kivy 1.10.0
#:import CoreImage kivy.core.image.Image
#:import os os

<EditStatePopup>:
    title: "Update State"
    size_hint: None, None
    size: 300, 300
    auto_dismiss: False

    BoxLayout:
        orientation: "vertical"
        GridLayout:
            cols: 2
            Label:
                text: "Id"
            Label:
                id: stateId
                text: root.col_data[0]
            Label:
                text: "Name"
            TextInput:
                id: stateName
                text: root.col_data[1]
            Label:
                text: "Code"
            TextInput:
                id: stateCode
                text: root.col_data[2]

            Button:
                size_hint: 1, 0.4
                text: "Cancel"
                on_release: root.dismiss()

            Button:
                size_hint: 1, 0.4
                text: "Ok"
                on_release:
                    root.package_changes(stateName.text, stateCode.text)
                    app.root.update_states(root)
                    root.dismiss()



<SelectableButton>:
    # Draw a background to indicate selection
    canvas.before:
        Color:
            rgba: (.0, 0.9, .1, .3) if self.selected else (0, 0, 0, 1)
        Rectangle:
            pos: self.pos
            size: self.size

<RV>:
    BoxLayout:
        orientation: "vertical"

        GridLayout:
            size_hint: 1, None
            size_hint_y: None
            height: 25
            cols: 3

            Label:
                text: "Id"
            Label:
                text: "Name"
            Label:
                text: "Code"

        BoxLayout:
            RecycleView:
                viewclass: 'SelectableButton'
                data: [{'text': str(x)} for x in root.data_items]
                SelectableRecycleGridLayout:
                    cols: 3
                    default_size: None, dp(26)
                    default_size_hint: 1, None
                    size_hint_y: None
                    height: self.minimum_height
                    orientation: 'vertical'
                    multiselect: True
                    touch_multiselect: True



<DropdownButton@Button>:
    border: (0, 16, 0, 16)
    text_size: self.size
    valign: "middle"
    padding_x: 5
    size_hint_y: None
    height: '30dp'
    background_color: 90 , 90, 90, 90
    color: 0, 0.517, 0.705, 1



<MenuButton@Button>:
    text_size: self.size
    valign: "middle"
    padding_x: 5
    size : (80,30)
    size_hint : (None, None)
    background_color: 90 , 90, 90, 90
    background_normal: ''
    color: 0, 0.517, 0.705, 1
    border: (0, 10, 0, 0)


<MainMenu>:
    states: states
    dropdown: dropdown

    BoxLayout:
        orientation: 'vertical'
        #spacing : 10

        BoxLayout:
            canvas.before:
                Rectangle:
                    pos: self.pos
                    size: self.size

            size_hint_y: 1

            MenuButton:
                id: btn
                text: 'View'
                size : (60,30)
                on_release: dropdown.open(self)

            CustDrop:
                id: dropdown
                auto_width: False
                width: 150

                DropdownButton:
                    text: 'State'
                    size_hint_y: None
                    height: '32dp'
                    #on_release: dropdown3.open(self)
                    on_release: root.display_states()

                DropdownButton:
                    text: 'City'
                    size_hint_y: None
                    height: '32dp'
                    #on_release: dropdown3.open(self)
                    on_release: root.display_city()

        BoxLayout:
            canvas.before:
                Rectangle:
                    pos: self.pos
                    size: self.size

                Color:
                    rgb: (1,1,1)

            AsyncImage:
                source: "clipboard.jpeg"    # "gst_image/add.jpg"
                #on_release: os.system("python m_State.py")

            Label:
                size_hint_x: 22

        BoxLayout:
            id: states
            size_hint_y: 9

        Label:
            size_hint_y: 9

输出