使用按钮打开和关闭 matplotlib 小部件

Question

到目前为止，我所写内容的目的是在我的 GUI 中有一个“温度”按钮，按下该按钮会打开我单独制作的 matplotlib 图 (mplwidget.py)。

但是，当我运行代码时，应用程序和小部件同时打开，并且温度按钮似乎没有任何功能（即使我关闭小部件，按下按钮也不会再次打开它）。

import sys
from PyQt5.QtCore import QCoreApplication

from PyQt5.QtGui import QIcon
from PyQt5.QtWidgets import QApplication, QWidget, QMainWindow, QPushButton, QAction, QMessageBox
from PyQt5.uic.properties import QtGui

from mplwidget import animate #import animation widget

class window(QMainWindow):

    def __init__(self):
        super(window, self).__init__()
        self.setGeometry(50, 50, 500, 300)
        self.setWindowTitle('Temperature Control')
        self.setWindowIcon(QIcon('adn.png'))

        extractAction = QAction('&Quit', self)
        extractAction.setShortcut('Ctrl+Q')
        extractAction.setStatusTip('leave the app')
        extractAction.triggered.connect(self.close_application)

        self.statusBar()

        mainMenu = self.menuBar()
        fileMenu = mainMenu.addMenu('&File')
        fileMenu.addAction(extractAction)

        self.home()

    def home(self):
        btn = QPushButton('quit', self)
        btn.clicked.connect(self.close_application)
        btn.resize(btn.sizeHint())
        btn.move(0, 100)

        button = QPushButton('Temperature',self)
        button.clicked.connect(self.opengraph)
        button.move(50,200)
        self.show()

    def opengraph(self):
        animate()

    def close_application(self):

        choice = QMessageBox.question(self, 'Message',
                                     "Are you sure to quit?", QMessageBox.Yes |
                                     QMessageBox.No, QMessageBox.No)

        if choice == QMessageBox.Yes:
            sys.exit()
        else:
            pass

if __name__ == "__main__":

    def run():
        app = QApplication(sys.argv)
        Gui = window()
        sys.exit(app.exec_())

run()

mplwidget 在下面

def GraphWidget():

    fig = plt.figure()
    ax1 = fig.add_subplot(1,1,1)

    Time = []
    Temp = []

    def animate(i):

        x = datetime.datetime.now()
        y = numpy.random.randint(48,52)
        Time.append(x)
        Temp.append(int(y))    

    #    print (Temp)
        ax1.plot(Time,Temp)

    ani = animation.FuncAnimation(fig,animate, interval=1000)
    plt.show()

Answer 1

试试看：

import sys
from PyQt5.QtGui     import QIcon
from PyQt5.QtWidgets import QApplication, QMainWindow, QPushButton, QAction, QMessageBox

from mplwidget import MplWindow                     # +++

class window(QMainWindow):

    def __init__(self):
        super(window, self).__init__()
        self.setGeometry(50, 50, 500, 300)
        self.setWindowTitle('Temperature Control')
        self.setWindowIcon(QIcon('adn.png'))
        extractAction = QAction('&Quit', self)
        extractAction.setShortcut('Ctrl+Q')
        extractAction.setStatusTip('leave the app')
        extractAction.triggered.connect(self.close_application)
        self.statusBar()
        mainMenu = self.menuBar()
        fileMenu = mainMenu.addMenu('&File')
        fileMenu.addAction(extractAction)

        self.matplWindow = MplWindow()               # +++

        self.home()


    def home(self):
        btn = QPushButton('quit', self)
        btn.clicked.connect(self.close_application)
        btn.resize(btn.sizeHint())
        btn.move(0, 100)
        button = QPushButton('Temperature',self)
        button.clicked.connect(self.opengraph)
        button.move(50,200)
        self.show()

    def opengraph(self):
        self.matplWindow.funAnimation()              # +++

    def close_application(self):
        choice = QMessageBox.question(self, 'Message',
                                     "Are you sure to quit?", QMessageBox.Yes |
                                     QMessageBox.No, QMessageBox.No)
        if choice == QMessageBox.Yes:
            sys.exit()
        else:
            pass

if __name__ == "__main__":
    app = QApplication(sys.argv)
    Gui = window()
    sys.exit(app.exec_())

mplwidget.py

import matplotlib.pyplot as plt
import numpy
import datetime
import matplotlib.animation as animation
from PyQt5.QtWidgets import QDialog, QApplication, QPushButton, QVBoxLayout


class MplWindow(QDialog):
    Time = []
    Temp = []
    def __init__(self, parent=None):
        super(MplWindow, self).__init__(parent)

    def funAnimation(self):        
        self.fig = plt.figure()
        self.ax1 = self.fig.add_subplot(1,1,1)
        self.ani = animation.FuncAnimation(self.fig, self.animate, interval=1000)
        plt.show()

    def animate(self, i):
        x = datetime.datetime.now()
        y = numpy.random.randint(48,52)
        self.Time.append(x)
        self.Temp.append(int(y))    
        self.ax1.plot(self.Time, self.Temp)

Answer 2

问题是plt.show() 本身无法启动事件循环，因为由于 QT 窗口打开，事件循环已经在运行。在这种情况下，需要调用fig.show()，其中fig 是正在使用的数字。

这反过来又导致mplwidget.py 模块中的函数实际返回的问题。一旦它返回动画的引用就会丢失并且会被垃圾回收；因此屏幕上不会出现动画。

解决的办法是让函数返回动画，并将其存储在主程序的某处。

import sys
from PyQt5.QtCore import QCoreApplication

from PyQt5.QtGui import QIcon
from PyQt5.QtWidgets import QApplication, QWidget, QMainWindow, QPushButton, QAction, QMessageBox
from PyQt5.uic.properties import QtGui

from mplwidget import showgraph

class window(QMainWindow):

    def __init__(self):
        super(window, self).__init__()
        self.setGeometry(50, 50, 500, 300)
        self.setWindowTitle('Temperature Control')
        self.setWindowIcon(QIcon('adn.png'))

        extractAction = QAction('&Quit', self)
        extractAction.setShortcut('Ctrl+Q')
        extractAction.setStatusTip('leave the app')
        extractAction.triggered.connect(self.close_application)

        self.statusBar()

        mainMenu = self.menuBar()
        fileMenu = mainMenu.addMenu('&File')
        fileMenu.addAction(extractAction)

        self.home()

    def home(self):
        btn = QPushButton('quit', self)
        btn.clicked.connect(self.close_application)
        btn.resize(btn.sizeHint())
        btn.move(0, 100)

        button = QPushButton('Temperature',self)
        button.clicked.connect(self.opengraph)
        button.move(50,200)
        self.show()

    def opengraph(self):
        self.store = showgraph()

    def close_application(self):

        choice = QMessageBox.question(self, 'Message',
                                     "Are you sure to quit?", QMessageBox.Yes |
                                     QMessageBox.No, QMessageBox.No)

        if choice == QMessageBox.Yes:
            sys.exit()
        else:
            pass

if __name__ == "__main__":

    def run():
        app = QApplication(sys.argv)
        Gui = window()
        sys.exit(app.exec_())

run()

mplwidget.py：

import matplotlib.pyplot as plt
import datetime
import numpy
import matplotlib.animation as animation

def showgraph():

    fig = plt.figure()
    ax1 = fig.add_subplot(1,1,1)

    Time = []
    Temp = []

    def animate(i):

        x = datetime.datetime.now()
        y = numpy.random.randint(48,52)
        Time.append(x)
        Temp.append(int(y))    

        ax1.plot(Time,Temp)

    ani = animation.FuncAnimation(fig,animate, interval=1000)
    fig.show()
    return fig, ani