在我生命中，我似乎无法弄清楚如何在kv中使用MDToolBar right_action_items:来切换屏幕。我知道用按钮on_release:可以添加一个简单的app.root.current = 'analyzer'（我将屏幕定义为“分析器”和“主”）。
但是，您无法将此代码添加到kv中的right_action_items: Lambda x: app.root.current = 'analyzer'中。
因此，我尝试在python中添加一个函数，该函数将在我的Manager(ScreenManager)->
def change_screen(self, inst):
Manager.current = f'{inst.ids.main.text}'
但是它不起作用...我迷路，困惑，害怕...帮助。我。请...
main.py
from kivymd.app import MDApp
from kivymd.theming import ThemeManager
from kivymd.uix.dialog import MDDialog
from kivy.uix.screenmanager import Screen, ScreenManager
from kivymd.uix.list import TwoLineListItem
from kivymd.uix.button import MDIconButton
from kivymd import *
from PyDictionary import PyDictionary
import sys
import json
import requests
class Manager(ScreenManager):
def change_screen(self, inst):
Manager.current = f'{inst.ids.main.text}'
class Main(Screen):
"""main application goes here"""
def close_dialog(self, obj):
self.dialog.dismiss()
def show_data(self):
message = """
Think of Probably Knot (PK) as a study
guide of sorts. Helping the user guide
himself.
This little program was designed to help
re-think ones sentences and therefore
find new solutions. By changing ones
perception, things can become more clear
where once they were misunderstood.
PK re-shuffle a word from an input
sentence to help rephrase ones
orignal sentence. To better
understand problems and ideas by
changing the angle of perception
with more elegant solutions.
"""
close = MDIconButton(icon="close-circle", on_release=self.close_dialog)
#more = MDIconButton(icon="more")
self.dialog = MDDialog(title="Probably Knot Helper", text=message,
size_hint=(0.8, 1), buttons=[close])
self.dialog.open()
class Analyzer(Screen):
def analyze(self, main): # main is pointing to ---> Main().show_data()
"""Analyse data with PyDictionary"""
sent = main.ids.sentence.text.lower()
wrd = main.ids.word.text.lower()
print(sent, wrd)
# Definition Section #
dictionary = PyDictionary()
define_wrd = dictionary.meaning(wrd)
if wrd != '' and sent != '':
API_KEY = 'a701e74e453ee6695e450310340401f5'
URL = f'http://words.bighugelabs.com/api/2/{API_KEY}/{wrd}/json'
if wrd not in sent:
print("i made it")
error = MDDialog(title="Error", text=f"Word: '{wrd}' is not in\n\n'{sent}'")
error.open()
else:
r = requests.get(URL) # get's url json file
j = json.loads(r.text) # loads json into 'j' as a dict
if type(j) == dict: # check is 'j' variable is coming in as a Dict holds the new sentences new = f"{result}\n"
final_set = set()
try:
for w in j['adjective']['syn']:
final_set.add(w)
except KeyError:
print(f'Adjective for "{wrd}" is not found.')
try:
for w in j['noun']['syn']:
final_set.add(w)
except KeyError:
print(f'Noun for "{wrd}" is not found.')
try:
for w in j['verb']['syn']:
final_set.add(w)
except KeyError:
print(f'Verb for "{wrd}" is not found.')
item = TwoLineListItem(text=f"Original: {sent}", secondary_text=f"{wrd}")
self.ids.container.add_widget(item)
for word in final_set:
item = TwoLineListItem(text=f"{sent.replace(wrd, word)}", secondary_text=f"{word}")
self.ids.container.add_widget(item)
# try:
# for num, w in enumerate(j['adjective']['syn'], 1):
# item = OneLineListItem(text=f"{num}: {sent.replace(wrd, w)}\n")
# self.ids.container.add_widget(item)
# except KeyError:
# print(f'Adjective for "{wrd}" is not found.')
# try:
# for num, w in enumerate(j['noun']['syn'], 1):
# item = OneLineListItem(text=f"{num}: {sent.replace(wrd, w)}\n")
# self.ids.container.add_widget(item)
# except KeyError:
# print(f'Noun for "{wrd}" is not found.')
# try:
# for num, w in enumerate(j['verb']['syn'], 1):
# item = OneLineListItem(text=f"{num}: {sent.replace(wrd, w)}\n")
# self.ids.container.add_widget(item)
# except KeyError:
# print(f'Verb for "{wrd}" is not found.')
class ProbablyKnotApp(MDApp):
def build(self):
self.theme_cls = ThemeManager()
self.theme_cls.theme_style = "Dark"
self.theme_cls.primary_palette = "Amber"
self.theme_cls.primary_hue = "A700"
return Manager()
if __name__ == "__main__":
ProbablyKnotApp().run()
kv
<Manager>:
Main:
id: main
name: 'main'
Analyzer:
id: analyze
name: 'analyzer'
<Main>:
BoxLayout:
orientation: 'vertical'
MDToolbar:
id: toolbar
title: "Probably Knot v3"
md_bg_color: app.theme_cls.primary_color
right_action_items: [["help-circle-outline", lambda x: app.root.get_screen('main').show_data()]]
MDFloatLayout:
MDTextField:
id: sentence
icon_right: "book-open-outline"
icon_right_color: app.theme_cls.primary_color
hint_text: "Enter Sentence"
helper_text: "Write a problem statement to analyze"
helper_text_mode: "on_focus"
multiline: False
pos_hint: {'center_x': 0.5, 'center_y': 0.7}
size_hint_x: None
width: root.width - dp(20)
MDTextField:
id: word
icon_right: "lead-pencil"
icon_right_color: app.theme_cls.primary_color
hint_text: "Enter Word"
helper_text: "Write ONE word from the above sentence"
helper_text_mode: "on_focus"
multiline: False
pos_hint: {'center_x': 0.5, 'center_y': 0.6}
size_hint_x: None
width: root.width - dp(20)
MDIconButton:
icon: "brain"
pos_hint: {'center_x': 0.5, 'center_y': 0.4}
user_font_size: 64
on_press: app.root.get_screen('analyzer').analyze(root)
on_release: app.root.current = 'analyzer'
# MDRectangleFlatButton:
# text: "help"
# pos_hint: {'center_x': 0.75, 'center_y': .1}
# on_release: app.root.get_screen('main').show_data()
<Analyzer>:
BoxLayout:
orientation: 'vertical'
MDToolbar:
id: toolbar
title: "Probably Knot v3"
md_bg_color: app.theme_cls.accent_color
right_action_items: [["backburger", lambda x: main.change_screen(root)], ["help-circle-outline", lambda x: app.root.get_screen('main').show_data()]]
ScrollView:
MDList:
id: container
答案 0 :(得分：1)
我遇到了同样的问题，我没有找到完美的解决方案，但是我找到了一种补救方法。
我用right_action_items内的MDFloatActionButton代替了MDToolbar：
MDToolbar:
title: 'Settings'
elevation: 10
MDFloatingActionButton:
icon: 'keyboard-backspace'
theme_text_color: 'Custom'
elevation: 0
md_bg_color: app.theme_cls.primary_color
enter code here on_release: root.ids.screen_manager.current = 'Home'
答案 1 :(得分：0)
感谢雅克的回答。它适用于我的应用程序。
我也在 KivyMD 中找到了这个解决方案
https://github.com/kivymd/KivyMD/issues/213#issuecomment-598703010
我的代码：
# .kv file
MDToolbar:
type: "bottom"
right_action_items: [["clock", lambda x : app.set_screen('ss')]]
# 'ss' is the Screen name.
# .py file class Main(MDApp):
def set_screen(self, screen_name):
self.root.current = screen_name