如何在 Kivy 代码中加入我的 Python 方法？

Question

我用 Python 编写了一个小程序，它在两个类别之间随机选择并相应地对数据帧进行子集化。 完成后，它会选择一行并提出问题和一个潜在的选择。 问题和选择位于两列不同列下的数据框行中。 到目前为止，它运行良好； 问题是当我尝试将其与 kivy 合并时。

我不明白动作的顺序是如何发生的。 基本上，我希望能够通过 kivy 文件在屏幕上包含问题和选择。 到目前为止，我能够展示它们，但看起来问题中的值与选择列中的值不匹配。 我的直觉告诉我，我的 kivy 文件运行“Choosing_category”两次，而不是只运行一次并获取适当的输出。 有谁知道我该如何解决这个问题？

这是我到目前为止所拥有的：

尝试应用程序

import kivy
from kivy.app import App
import pandas as pd
import numpy as np

from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
kivy.require('1.11.1')

class QuestionWindows(Screen):
    def __init__(self,  **kwargs):
        super(QuestionWindows, self).__init__(**kwargs)
        self.prob = ''
        self.word = ''
        self.choice1 = ''
        self.word = ''
        self.df = pd.DataFrame()

    def _get_df(self):
        df = pd.DataFrame([['new', 'What is you favorite color?', 'blue?', 'blue', 0,0,0,0,0],
                           ['familiar', 'What is your favorite fruit?', 'apple?', 'apple', 0,0,0,0,0],
                           ['new', 'What is your favorite vegetable?', 'carrot?', 'carrot',0,0,0,0,0]],
                          columns=['state', 'questions', 'choice1', 'answer', 'cnt', 'count_correct', 'error_count', 'total_error', 'total_correct'])
        return df

    def choosing_category(self):
        # Loading the dataframe
        self.df = self._get_df()

        # Generating the category for which the question/answer will be sampled from
        self.prob = np.random.choice(['new', 'familiar'], 1, p=[0.7, 0.3])
        # Dealing with the condition on whether the state 'familiar' is not found in the data set
        if self.prob not in self.df['state'].values:
            self.prob = ['new']
            self.prob = self.prob
        else:
            self.prob = self.prob
        # Making sure to present a question/answer that hasn't been presented recently
        if len(self.df[(self.df['state'] == self.prob[0]) & (self.df['cnt'] == 0)]) > 0:
            self.tmp_df = self.df[(self.df['state'] == self.prob[0]) & (self.df['cnt'] == 0)]

        elif len(self.df[(self.df['state'] == prob)]) > 0:
            self.tmp_df = self.df[(self.df['state'] == prob)]
        else:
            self.prob = ['familiar']
            self.tmp_df = self.df[(self.df['state'] == self.prob) & (self.df['cnt'] == 0)]

        # Getting the question from the temporary dataframe
        self.word = np.random.choice(self.tmp_df['questions'])

        # Getting the choice from the question that was previously selected
        self.choice1 = self.df.loc[self.tmp_df[self.tmp_df['questions'] == self.word].index, "choice1"].values
        return str(self.word), str(self.choice1[0])


class QuestionsApp(App):

    def build(self):
        self.screen_manager = ScreenManager()
        self.question_page = QuestionWindows()
        self.screen_manager.add_widget(self.question_page)
        return self.screen_manager


if __name__ == "__main__":

    tryapp = QuestionsApp()
    tryapp.run()

问题.kv

    <SmoothButton@Button>:
    background_color: (0.0, 0.4, 0.95, 1)
    background_normal: ''
    font_size: 20

<QuestionButton@Button>:
    background_color: (0,0,0,0)
    background_normal: ''
    back_color: (0.0, 0.4, 0.95, 1)
    border_radius: [2,2,22,22]
    color: (0.0, 0.4, 0.95, 1)
    bold: True
    canvas.before:
        Color:
            rgba: self.back_color
        RoundedRectangle:
            size: self.size
            pos: self.pos
            radius: self.border_radius

<QuestionWindows>
    #id: question_page
    name: "question_page"
    FloatLayout:
        QuestionButton:
            id: question
            text: root.choosing_category()[0]
            pos_hint: {'x': 0.1, 'y': 0.77}
            size_hint: 0.8, 0.17
            back_color: 1, 1, 1, 1
            background_normal: ''
            font_size: 20
            background_down: ''
        SmoothButton:
            id: choice1
            text: root.choosing_category()[1]
            pos_hint: {'x': 0.1, 'y': 0.27}
            size_hint: 0.8, 0.1

Answer 1

您对choosing_category()方法被调用两次是正确的。 解决这个问题的一个好方法是使用我建议的on_enter()方法。 您可以将QuestionWindows类修改为：

class QuestionWindows(Screen):
    word = StringProperty('')
    choice1 = StringProperty('')
.
.
.

    def choosing_category(self):
        # Loading the dataframe
        self.df = self._get_df()
        .
        .
        .
        # Getting the question from the temporary dataframe
        self.word = np.random.choice(self.tmp_df['questions'])

        # Getting the choice from the question that was previously selected
        # Note the added [0] at the end of this line
        self.choice1 = self.df.loc[self.tmp_df[self.tmp_df['questions'] == self.word].index, "choice1"].values[0]
        # return str(self.word), str(self.choice1[0])


    def on_enter(self, *args):
        self.choosing_category()

这向QuestionWindows类添加了两个属性，这些属性由choosing_categroy()方法更新，并且可以在kv引用：

<QuestionWindows>:
    #id: question_page
    name: "question_page"
    FloatLayout:
        QuestionButton:
            id: question
            text: root.word
            pos_hint: {'x': 0.1, 'y': 0.77}
            size_hint: 0.8, 0.17
            back_color: 1, 1, 1, 1
            background_normal: ''
            font_size: 20
            background_down: ''
        SmoothButton:
            id: choice1
            text: root.choice1
            pos_hint: {'x': 0.1, 'y': 0.27}
            size_hint: 0.8, 0.1

这种方法的一个优点是您可以简单地调用choosing_category()并且问题和选择将更新。