在 kivy/python 中的应用程序中自动计算结果

Question

是否可以在kivy中获得自动结果计算？我认为我有 3 个 TextInput 字段，当其中至少 2 个填写 3 时，我会得到结果。

我想到了类似的东西：

--------------
|  2         |  --> TextInput 1
--------------
|result = 5  |  --> TextInput 2
-------------
|    3       |  ---> TextInput 3
--------------

Or

--------------
| result = 5 |  --> TextInput 1
--------------
|     2      |  --> TextInput 2
-------------
|    3       |  ---> TextInput 3
--------------

输入至少 2 个数字后，结果应该会自动出现。

我的.py：

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen


class HomeScreen(Screen):
    pass


class CalculatorHome(Screen):
    pass


GUI = Builder.load_file("kv/my.kv")


class MainApp(App):
    def build(self):
       return GUI

    def change_screen(self, screen_name, direction):
        # Get the screen manager from the kv file
        screen_manager = self.root.ids['screen_manager']
        screen_manager.current = screen_name
        screen_manager.transition.direction = direction

    def clear_text(self, *args):
        for ar in args:
            ar.text = ''


MainApp().run()

使用 TextIput 计算.kv

<CalculatorHome>:
    FloatLayout:

        GridLayout:

            rows:3
            pos_hint: {"top": .8, "left": 1 }
            size_hint: 1, .4

            TextInput:
                id: number1
                multiline: False
            TextInput:
                id: number2
                multiline: False
            TextInput:
                id: number3
                multiline: False

        GridLayout:

            rows:1
            pos_hint: {"top": .3, "left": 1 }
            size_hint: 1, .1

            Button:
                text: "CLEAR"
                on_press: app.clear_text(number1, number2, number3 )

Answer 1

如果你把一些东西从kv放到python文件中会更简单，像这样：

class MainApp(App):
    def build(self):
       # if you use ScreenManager you should return it in build function
       self.sm = ScreenManager()
       # creating the objects of screen classes
       self.homescreen = HomeScreen()
       self.calculatorhome = CalculatorHome()
       # don't forget to set names of screens in kv file!
       self.sm.add_widget(self.homescreen)
       self.sm.add_widget(self.calculatorhome)
       self.t1 = ObjectProperty(None)
       self.t2 = ObjectProperty(None)
       self.t3 = ObjectProperty(None)
       Clock.schedule_once(self.gettextinputs)
       return self.sm

    def gettextinputs(self, *args):
        # get textinputs from kv
        self.t1 = self.calculatorhome.ids.number1
        self.t2 = self.calculatorhome.ids.number2
        self.t3 = self.calculatorhome.ids.number3

        # bind on change function calling
        self.t1.bind(text = lambda e1, e2: self.checkinputs())
        self.t2.bind(text = lambda e1, e2: self.checkinputs())
        self.t3.bind(text = lambda e1, e2: self.checkinputs())

    def checkinputs(self):
        if self.t1.text and self.t2.text:
            result = int(self.t1.text) + int(self.t2.text)
            self.t3.text = str(result)
        elif self.t1.text and self.t3.text:
            result = int(self.t1.text) + int(self.t3.text)
            self.t2.text = str(result)
        elif self.t2.text and self.t3.text:
            result = int(self.t2.text) + int(self.t3.text)   
            self.t1.text = str(result)

所以现在当您更改文本输入的文本时，空的将显示其他两个的结果。