关闭window后方法仍然是运行

Question

我无法理解 window 对象的工作原理。我通过 matplotlib 在二级 window 上有一个实时绘图。该图每秒更新一次新的计算值。我期望的是每当我关闭第二个 window 时停止运行并在我重新打开它时重新启动的方法。我可以在关闭第二个 window 时重置数组值，但如前所述，这种计算值的方法仍然是运行.

这是我的代码（最初使用传感器，我修改它以生成随机数）：

from PyQt5 import QtCore
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QVBoxLayout
import sys
import random
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure


# The main window 
class Window(QWidget):
    def __init__(self):
        super().__init__()
 
        self.setGeometry(200,200, 400,300)
        self.setWindowTitle('Test')
        self.demo = None
        
        self.create_buttons()
        
    def create_buttons(self):
        btn1 = QPushButton('Open window', self)
        btn1.setGeometry(100,100, 100,100)
        btn1.clicked.connect(self.open_w)
        
    def open_w(self):
        if self.demo is None:
            self.demo = AppDemo()
        self.demo.show()
        
# Second window, where I plot the data
class AppDemo(QWidget):
    def __init__(self):
        super().__init__()
        self.resize(650, 500)
        self.plotwidget = QWidget(self)
        self.chart = Matplotlibwidget()
        self.chart.plot_widget(self.plotwidget, self.chart)
        
    def closeEvent(self, event):
        event.accept()
        func.start_lists()
        print('Window closed')
        
# My widget for my graph        
class Matplotlibwidget(FigureCanvas):
    def __init__(self, parent=None):
        fig = Figure()
        self.axes = fig.add_subplot(111)
        
        FigureCanvas.__init__(self, fig)
        self.setParent(parent)
        FigureCanvas.updateGeometry(self)      
    
    def plot_widget(self, canvasWidget, graph):
        self.layoutvertical = QVBoxLayout(canvasWidget)
        self.layoutvertical.addWidget(graph)        
        timer = QtCore.QTimer(self)
        timer.timeout.connect(self.plotting)
        timer.start(1000)
              
    def plotting(self):
        self.y = func.calculate()
        func.appends(self.y)
        self.axes.cla()
        self.axes.plot(func.x, func.y)
        self.draw()

# This is a generic class I use to calculate the data, originally this is a class for my sensor
class FuncTime ():
    def __init__(self):
        self.start_lists()
         
    def start_lists(self):
        self.x, self.y = [0], [1]
        
    def calculate(self):
        return self.y[-1] + self.y[-1] * random.uniform(-0.1, 0.1)
        
    def appends(self, y):
        print(self.x[-1], ', ', self.y[-1])
        self.x.append(self.x[-1] + 1)
        self.y.append(y)

  
app = QApplication(sys.argv)
func = FuncTime()
window = Window()
window.show()
sys.exit(app.exec_())

Answer 1

window关闭并不意味着定时器停止，您必须使用QTimer的停止方法来实现它。

from functools import cached_property
import random
import sys

from PyQt5.QtCore import QTimer
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QVBoxLayout

from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure


class Window(QWidget):
    def __init__(self):
        super().__init__()

        self.setGeometry(200, 200, 400, 300)
        self.setWindowTitle("Test")
        self.create_buttons()

    @cached_property
    def demo(self):
        return AppDemo()

    def create_buttons(self):
        btn1 = QPushButton("Open window", self)
        btn1.setGeometry(100, 100, 100, 100)
        btn1.clicked.connect(self.open_w)

    def open_w(self):
        self.demo.chart.start()
        self.demo.show()


class AppDemo(QWidget):
    def __init__(self):
        super().__init__()
        self.resize(650, 500)

        self.chart = Matplotlibwidget()

        lay = QVBoxLayout(self)
        lay.addWidget(self.chart)

    def closeEvent(self, event):
        super().closeEvent(event)
        self.chart.stop()


class Matplotlibwidget(FigureCanvas):
    def __init__(self, parent=None):
        fig = Figure()
        self.axes = fig.add_subplot(111)
        FigureCanvas.__init__(self, fig)
        self.setParent(parent)
        self.updateGeometry()

    @cached_property
    def timer(self):
        return QTimer(interval=1000, timeout=self.handle_timeout)

    @cached_property
    def func_time(self):
        return FuncTime()

    def start(self):
        self.timer.start()

    def stop(self):
        self.timer.stop()
        self.func_time.reset()

    def handle_timeout(self):
        self.plotting()

    def plotting(self):
        self.y = self.func_time.calculate()
        self.func_time.appends(self.y)
        self.axes.cla()
        self.axes.plot(self.func_time.x, self.func_time.y)
        self.draw()


class FuncTime:
    def __init__(self):
        self.reset()

    def reset(self):
        self.x, self.y = [0], [1]

    def calculate(self):
        return self.y[-1] + self.y[-1] * random.uniform(-0.1, 0.1)

    def appends(self, y):
        print(self.x[-1], ", ", self.y[-1])
        self.x.append(self.x[-1] + 1)
        self.y.append(y)


app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())

关闭window后方法仍然是运行

Method is still running after closing window

python

matplotlib

pyqt5