从运行的Kivy应用程序访问数据

Question

我正在使用使用Kivy应用程序实现的GUI界面的程序。我的最终目标是在Kivy Textbox中输入所需的电压，并使用Arduino + DAC转换器进行设置。目前，我只是想从我的主体中的Kivy应用程序外部的文本输入中访问电压，以便我可以清晰地将GUI与与Arduino的通信和其他必要的计算分开。

问题在于，在app.run（）之后，该程序不会继续进行，直到关闭Kivy应用程序并丢失了输入的电压为止。我已经尝试使用多处理库，但是只要应用程序运行，start（）函数也可以运行。我也不确定访问电压的最佳方法是什么，我尝试将其作为GUI的班级成员，但这也许不是一个好主意。

这是我的gui.py代码：

    from kivy.app import App
    from kivy.uix.label import Label
    from kivy.uix.gridlayout import GridLayout
    from kivy.uix.textinput import TextInput
    from kivy.properties import StringProperty, NumericProperty
    from kivy.uix.button import Button
    
    class GUI_GridLayout(GridLayout):
    
        voltage_label_1 = StringProperty("Voltage 1?")
        voltage_label_2 = StringProperty("Voltage 2?")
    
        voltage_input_1 = TextInput()
        voltage_input_2 = TextInput()
    
        submit_button_label_1 = StringProperty("Submit 1")
        submit_button_label_2 = StringProperty("Submit 2")
    
        voltage_output_1 = NumericProperty(0)
        voltage_output_2 = NumericProperty(0)
    
        def press_1(self):
            voltage_1 = self.voltage_input_1.text
            self.voltage_output_1  = float(voltage_1)
    
        def press_2(self):
            voltage_2 = self.voltage_input_2.text
            self.voltage_output_2 = float(voltage_2)
    
        def build(self):
            self.add_widget(Label(text=self.voltage_label_1))
            self.add_widget(self.voltage_input_1)
    
            self.add_widget(Label(text=self.voltage_label_2))
            self.add_widget(self.voltage_input_2)
    
            self.submit_button_1 = Button(text=self.submit_button_label_1)
            self.submit_button_1.bind(on_press=self.press_1)
            self.add_widget(self.submit_button_1)
    
            self.submit_button_2 = Button(text=self.submit_button_label_2)
            self.submit_button_2.bind(on_press=self.press_2)
            self.add_widget(self.submit_button_2)
    
    
    
    class apason_GUIApp(App):
        def build(self):
            return GUI_GridLayout()

相应的kv文件：

#:kivy 1.0.9

<GUI_GridLayout>:

    cols: 3

    voltage_input_1: input_1
    voltage_input_2: input_2

    Label:
        font_size: 50
        text: str(root.voltage_label_1)

    TextInput:
        id: input_1
        font_size: 50
        multiline: False
        text: root.voltage_input_1.text

    Button:
        font_size: 50
        text: str(root.submit_button_label_1)
        on_press: root.press_1()

    Label:
        font_size: 50
        center_x: root.width / 4
        text: str(root.voltage_label_2)

    TextInput:
        id: input_2
        font_size: 50
        multiline: False
        text: root.voltage_input_2.text

    Button:
        font_size: 50
        text: str(root.submit_button_label_2)
        on_press: root.press_2()

这是我的主要：

import GUI.GUI as gui
import multiprocessing as multiproc
import time

class GetVoltage:

    def __init__(self):
        self.voltage_1 = 0
        self.voltage_2 = 0

    def fetchVoltage(self, interface):
        self.voltage_1 = interface.voltage_output_1
        self.voltage_2 = interface.voltage_output_2

    def run(self, interface):
        while (True):

            self.fetchVoltage(interface)

            print(self.voltage_1)
            print(self.voltage_2)

            time.sleep(1)

if __name__ == '__main__':

    interface = gui.apason_GUIApp()
    interface_process = multiproc.Process(target=interface.run())

    checker = GetVoltage()
    checker_process = multiproc.Process(target=checker.run(interface))

    interface_process.start()
    checker_process.start()

Answer 1

由于运行main.py.py时，您已经有一个进程，因此您实际上只需要启动第二个进程即可。您可以使用a queue 。这是使用此方法的main.py.py的修改版本：

import GUI as gui
import multiprocessing as multiproc


class GetVoltage:
    def run(self, queue):
        while True:
            voltage = queue.get()  # get the data from the other process by using the Queue
            print(voltage)


if __name__ == '__main__':
    q = multiproc.Queue()

    # start the GetVoltage process
    checker = GetVoltage()
    checker_process = multiproc.Process(target=checker.run, args=(q,), daemon=True)
    checker_process.start()

    # start the App
    interface = gui.apason_GUIApp()
    interface.q = q
    interface.run()  # this does not return until the App closes

    # kill the GetVoltage process after the App exits
    checker_process.kill()

app代码中的几个次要更改：

def press_1(self):
    voltage_1 = self.voltage_input_1.text
    self.voltage_output_1 = float(voltage_1)
    App.get_running_app().q.put('voltage_1 = ' + voltage_1)  # put the data in the Queue

def press_2(self):
    voltage_2 = self.voltage_input_2.text
    self.voltage_output_2 = float(voltage_2)
    App.get_running_app().q.put('voltage_2 = ' + voltage_2)  # put the data in the Queue