如何解决“屏幕只显示一个空白的紫屏”问题？ [关闭]
Posted
技术标签:
【中文标题】如何解决“屏幕只显示一个空白的紫屏”问题？ [关闭]【英文标题】：how to aolve "The screen only shows a blank purple screen" issue? [closed] 【发布时间】：2021-04-12 00:35:49 【问题描述】：我正在将我的代码从 kivy 转换为 kivymd。但它没有在屏幕上显示任何内容。我无法找到问题......我该如何运行它......我正在使用pycharm。 它在 kivy 代码中运行良好...我查看了一些 kivymd 示例，然后对其进行了转换。
如果我的问题是适当的，请有人编辑它
.py 代码
from kivy.lang import Builder
from kivymd.app import MDApp
from kivy.uix.popup import Popup
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivymd.uix.boxlayout import MDBoxLayout
from kivymd.uix.gridlayout import MDGridLayout
from kivymd.uix.button import MDFlatButton
import sys, time, threading
import pyrebase
from kivymd.uix.screen import MDScreen
from kivy.uix.screenmanager import ScreenManager, Screen
from datetime import datetime, timedelta
import pandas_datareader.data as web
from kivymd.theming import ThemeManager
import pandas as pd
from kivymd.icon_definitions import md_icons
from kivy.utils import get_color_from_hex
import webbrowser
from kivymd.uix.screen import Screen
from kivymd.uix.list import MDList, ThreeLineListItem, ThreeLineAvatarIconListItem, OneLineListItem
from kivymd.uix.list import IconLeftWidget, ImageLeftWidget
from kivy.uix.scrollview import ScrollView
from kivy.uix.button import Button
from kivymd.uix.card import MDCardSwipe
from kivy.properties import ObjectProperty
import csv
from os import path
from kivy.uix.image import Image
from kivy.app import App
from kivy.uix.textinput import TextInput
from kivy.lang import Builder
from kivy.uix.gridlayout import GridLayout
from kivy.uix.floatlayout import FloatLayout
from kivy.properties import NumericProperty, ListProperty, BooleanProperty, ObjectProperty, StringProperty
from kivy.uix.recycleview import RecycleView
from kivy.uix.recyclegridlayout import RecycleGridLayout
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.label import Label
import re
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
import pandas as pd
from kivy.clock import Clock
from functools import partial
from kivymd.uix.dialog import MDDialog
from kivymd.uix.textfield import MDTextField, MDTextFieldRound
from kivymd.uix.label import MDLabel
from kivymd.toast import toast
from kivy.core.window import Window
Window.size = (300, 500)
username = ''
class SelectableRecycleBoxLayout(FocusBehavior, LayoutSelectionBehavior,
RecycleGridLayout):
''' Adds selection and focus behaviour to the view. '''
class SelectableLabel(RecycleDataViewBehavior, MDLabel):
''' Add selection support to the Label '''
index = None
selected = BooleanProperty(False)
selectable = BooleanProperty(True)
txt_input = ObjectProperty(None)
stock_name = ObjectProperty(None)
stock_symbol = ObjectProperty(None)
purchase_price = ObjectProperty(None)
stop_loss = ObjectProperty(None)
highlight = ListProperty([1, 1, 1, 1])
def refresh_view_attrs(self, rv, index, data):
''' Catch and handle the view changes '''
self.index = index
return super(SelectableLabel, self).refresh_view_attrs(
rv, index, data)
def on_touch_down(self, touch):
''' Add selection on touch down '''
if super(SelectableLabel, 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
if is_selected:
# App.get_running_app().root.widget_1.ids.txt_input1.text = str(rv.data[index].get("text"))
xx = str(rv.data[index].get("text"))
if (xx.find('(NSI)') != -1):
x, y = xx.split(" (NSI)")
add_sym = '.NS'
else:
x, y = xx.split(" (BSE)")
add_sym = '.BO'
print(xx)
print(x)
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_name.text = x
f = pd.read_csv("Stock Tickers.csv", encoding="ISO-8859-1", engine='python')
fl = len(f.index)
file = pd.DataFrame(f, columns=['Symbols', 'Name', 'Exchange'])
for i in range(fl):
for index in range(1):
columnSeriesObj_sym = file.iloc[:, 0]
columnSeriesObj1 = file.iloc[:, 1]
columnSeriesObj_ex = file.iloc[:, 2]
before_sym, b = columnSeriesObj_sym.values[i].split('.')
if columnSeriesObj1.values[i] == App.get_running_app().root.get_screen(
'body_screen').widget_1.ids.stock_name.text:
App.get_running_app().root.get_screen(
'body_screen').widget_1.ids.stock_symbol.text = before_sym + add_sym
class RV(RecycleView):
def __init__(self, **kwargs):
super(RV, self).__init__(**kwargs)
class DropDownWidget(MDBoxLayout):
txt_input = ObjectProperty(None)
rv = ObjectProperty(None)
stock_name = ObjectProperty(None)
stock_symbol = ObjectProperty(None)
purchase_price = ObjectProperty(None)
stop_loss = ObjectProperty(None)
def back(self):
self.clear_texts()
MDApp.get_running_app().root.transition.direction = 'right'
MDApp.get_running_app().root.current = 'option_screen'
def clear_texts(self):
App.get_running_app().root.get_screen('body_screen').widget_1.ids.txt_input.text = ""
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_name.text = ""
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_symbol.text = ""
App.get_running_app().root.get_screen('body_screen').widget_1.ids.purchase_price.text = ""
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stop_loss.text = ""
def btn_input(self):
if App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_name.text == '':
toast('Please Select Stock')
elif App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_symbol.text == '':
toast('Please Select Stock')
elif App.get_running_app().root.get_screen('body_screen').widget_1.ids.purchase_price.text == '':
toast('Please Enter Purchase Price')
elif App.get_running_app().root.get_screen('body_screen').widget_1.ids.stop_loss.text == '':
toast('Please Enter Stoploss')
elif float(App.get_running_app().root.get_screen('body_screen').widget_1.ids.stop_loss.text) <= 100:
print("Stock Name:", App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_name.text,
"Stock Symbol:", App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_symbol.text)
print("Purchase Price:",
App.get_running_app().root.get_screen('body_screen').widget_1.ids.purchase_price.text,
"Stop Loss(%):", App.get_running_app().root.get_screen('body_screen').widget_1.ids.stop_loss.text)
# write data to csv file
file_name ="stoploss.csv"
if path.exists(file_name):
with open(file_name, "a+", newline='')as newFile:
fieldnames = ["Stock Name", "Stock Symbol", "Purchase Price", "Stop Loss(%)"]
newFileWriter = csv.DictWriter(newFile, fieldnames=fieldnames)
newFileWriter.writerow("Stock Name": App.get_running_app().root.get_screen(
'body_screen').widget_1.ids.stock_name.text,
"Stock Symbol": App.get_running_app().root.get_screen(
'body_screen').widget_1.ids.stock_symbol.text,
"Purchase Price": App.get_running_app().root.get_screen(
'body_screen').widget_1.ids.purchase_price.text,
"Stop Loss(%)": App.get_running_app().root.get_screen(
'body_screen').widget_1.ids.stop_loss.text)
else:
myFile = open(file_name, 'w+', newline='')
myData = [["Stock Name", "Stock Symbol", "Purchase Price", "Stop Loss(%)"],
[App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_name.text,
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stock_symbol.text,
App.get_running_app().root.get_screen('body_screen').widget_1.ids.purchase_price.text,
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stop_loss.text]]
with myFile:
writer = csv.writer(myFile)
writer.writerows(myData)
self.clear_texts()
else:
App.get_running_app().root.get_screen('body_screen').widget_1.ids.stop_loss.text = ''
toast(text='The Stoloss should be less then 100%')
class MyTextInput(MDTextFieldRound):
txt_input = ObjectProperty(None)
flt_list = ObjectProperty()
word_list = ListProperty()
stock_name = ObjectProperty(None)
stock_symbol = ObjectProperty(None)
purchase_price = ObjectProperty(None)
stop_loss = ObjectProperty(None)
# this is the variable storing the number to which the look-up will start
starting_no = NumericProperty()
suggestion_text = ''
def __init__(self, **kwargs):
super(MyTextInput, self).__init__(**kwargs)
def on_text(self, instance, value):
# find all the occurrence of the word
self.parent.parent.parent.ids.rv.data = []
if len(value) != 0:
matches = [word for word in self.word_list if word.lower().find(value.lower()) != -1]
# display the data in the recycleview
display_data = []
for i in matches:
display_data.append('text': i)
self.parent.parent.parent.ids.rv.data = display_data
# ensure the size is okay
if len(matches) <= 10:
self.parent.height = (50 + (len(matches) * 20))
else:
self.parent.height = 250
def keyboard_on_key_down(self, window, keycode, text, modifiers):
if self.suggestion_text and keycode[1] == 'tab':
self.ids.rv.refresh_from_data()
self.insert_text(self.suggestion_text + ' ')
return True
return super(MyTextInput, self).keyboard_on_key_down(window, keycode, text, modifiers)
class Body1(MDScreen):
def build(self):
f = pd.read_csv("Stock Tickers.csv", encoding="ISO-8859-1", engine='python')
fl = len(f.index)
file = pd.DataFrame(f, columns=['Symbols', 'Name', 'Exchange'])
wl = []
for i in range(fl):
for index in range(1):
columnSeriesObj = file.iloc[:, 1]
self.columnSeriesObj_ex = file.iloc[:, 2]
wl.append(columnSeriesObj.values[i] + " (" + self.columnSeriesObj_ex.values[i] + ")")
tp = tuple(wl)
self.widget_1 = DropDownWidget()
self.widget_1.ids.txt_input.word_list = wl
self.widget_1.ids.txt_input.starting_no = 3
self.add_widget(self.widget_1)
sm = ScreenManager()
sm.add_widget(Body1(name='body_screen1'))
class stockinput1App(MDApp):
def build(self):
kv = Builder.load_file("ss.kv")
return kv
if __name__ == "__main__":
stockinput1App().run()
.kv 代码
ScreenManager:
Body1:
<Body1>:
on_enter:root.build()
name: 'body_screen1'
canvas.before:
Color:
rgba: 155/255, 159/255, 250/255, 1
Rectangle:
pos: self.pos
size: self.size
<DropDownWidget>:
canvas.before:
Color:
rgba: 155/255, 159/255, 250/255, 1
Rectangle:
pos: self.pos
size: self.size
cols:1
id: DropDownWidget
stock_name: stock_name
stock_symbol: stock_symbol
purchase_price: purchase_price
stop_loss: stop_loss
txt_input: txt_input
rv: rv
orientation:'vertical'
spacing: '20dp'
MDToolbar:
title:'Add Stock'
type: "top"
size_hint_y:0.1
pos_hint: 'top':1.0
left_action_items: [["arrow-left", lambda x: root.back()]]
md_bg_color:152/255,87/255,189/255,1
elevation:10
MDBoxLayout:
spacing:'5dp'
orientation:'vertical'
MDCard:
md_bg_color:155/255, 159/255, 250/255, 1
pos_hint: 'center_x': .5, 'center_y': .5
elevation:0
orientation:'vertical'
spacing:'10dp'
MyTextInput:
id: txt_input
hint_text: "Search"
icon_right: "magnify"
icon_right_color:1,1,1,1
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:.9,.2
line_color_normal:184/255,187/255,252/255,1
normal_color:1,1,1,0
RV:
id: rv
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:1,0.6
MDCard:
md_bg_color:155/255, 159/255, 250/255, 1
orientation:'horizontal'
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:.9,.4
elevation:0
MDTextField:
id: stock_name
hint_text: "Stock Name"
readonly: True
multiline:True
mode:'rectangle'
required: True
outline_color:184/255,187/255,252/255,1
size:.5,.3
MDCard:
orientation:'horizontal'
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:.9,.4
elevation:0
md_bg_color:155/255, 159/255, 250/255, 1
MDTextField:
id: stock_symbol
hint_text: "Stock Symbol"
readonly: True
multiline:False
mode:'rectangle'
required: True
pos_hint: 'center_x': .5, 'center_y': .5
line_color_normal:184/255,187/255,252/255,1
MDCard:
orientation:'horizontal'
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:.9,.4
elevation:0
md_bg_color:155/255, 159/255, 250/255, 1
MDTextField:
id: purchase_price
hint_text: "Purchase Price"
input_filter: 'float'
multiline:False
mode:'rectangle'
required: True
line_color_normal:184/255,187/255,252/255,1
size:.5,.3
MDCard:
orientation:'horizontal'
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:.9,.4
elevation:0
md_bg_color:155/255, 159/255, 250/255, 1
MDTextField:
id: stop_loss
hint_text: "Stop Loss(%)"
input_filter: 'float'
max_text_length: 3
multiline:False
mode:'rectangle'
required: True
size:.5,.3
color_mode: 'custom'
line_color_normal:1,1,1,1
MDCard:
pos_hint: 'center_x': .5, 'center_y': .5
size_hint:.5,.5
elevation:0
md_bg_color:155/255, 159/255, 250/255, 1
MDRaisedButton:
text:"Submit"
pos_hint: 'center_x': .5, 'center_y': .6
size_hint:.5,.7
md_bg_color:40/255, 44/255, 177/255, 1
elevation:15
on_press: root.btn_input()
<MyTextInput>:
id: MyTextInput
mode:'rectangle'
readonly: False
multiline: False
<SelectableLabel>:
id: SelectableLabel
multiline: True
# Draw a background to indicate selection
canvas:
Color:
rgba: (218/255,112/255,214/255,.6) if self.selected else (1, 1, 1, 0.5)
Rectangle:
pos: self.pos if self.selected else (0,0)
size: self.size if self.selected else (0,0)
halign:'center'
<RV>:
canvas:
Color:
rgba: 1,1,1,1
Line:
width: 1.1
rectangle: self.x , self.y, self.width, self.height
height: 10
bar_width: 20
scroll_type:['bars']
viewclass: 'SelectableLabel'
SelectableRecycleBoxLayout:
cols:1
row_default_height: 30
row_force_default:True
default_size: self.size, dp(20)
default_size_hint: 1, None
size_hint_y: None
height: 300
multiselect: False
我正在分享 csv ,py,kv 文件的链接...here
【问题讨论】：
代码很长，您不会收到任何错误消息 - 所以我们只能建议使用print() 来查看变量中的值以及执行了哪部分代码。它被称为“打印调试”> 或者学习使用真正的调试器。
那是因为您的Body1 在您的kv 中被定义为一个空白的紫色屏幕。
【参考方案1】：
Kivy 中的一个错误导致on_enter 事件没有被调度为ScreenManager 中的初始Screen，因此您的build() 方法永远不会被调用。一种解决方法是自己调用它：
class stockinput1App(MDApp):
def build(self):
kv = Builder.load_file("ss.kv")
kv.get_screen('body_screen1').build()
return kv
另一个说明：从技术上讲，这不是错误，而是以下几行：
sm = ScreenManager()
sm.add_widget(Body1(name='body_screen1'))
正在创建ScreenManager 的第二个实例和Body1 的两个实例。然后所有这些都被忽略。可以删除这些行。整个 GUI 实际上是通过调用 Builder.load_file() 构建的。
【讨论】：
以上是关于如何解决“屏幕只显示一个空白的紫屏”问题？ [关闭]的主要内容，如果未能解决你的问题，请参考以下文章
如何解决 ActionScript 3 (AS3) 中的关闭问题
算法分析：我是不是正确分析了这些算法？如何解决此类问题[关闭]
我在披露指标中看到了双 V 形。为啥以及如何解决这个问题？ [关闭]