集成在 QScrollArea 中的 Matplotlib 无法在 mac OS 上正确刷新曲线

Question

我在 pyqt5 QScrollArea 中嵌入的 matplotlib 图有问题。我的问题是当我向下滚动时，好像只更新了 matplotlib 的顶部。例如，在下图中，曲线编号 35 以下的曲线未正确更新。

这只发生在 mac OS 但它运行在 Windows 10 上很好。我没有在代码中找到问题。

更新

在我看来，matplotlib 图与 QSrollBar 不匹配。我试着解释更多。当我使用 Qsrollbar 向下滚动时，Matplotlib 图正在下降但没有滚动条那么快。当我向下滚动时，我看到曲线的数量在增加。就好像 Qscrollbar 相对于 matplotlib 图更新太快了。

from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
import sys
import matplotlib
matplotlib.use('Qt5Agg')
import matplotlib.pyplot as plt
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
import numpy as np
import time

class Viewer(QMainWindow):
    def __init__(self, parent=None):
        super(Viewer, self).__init__()
        self.parent = parent
        #######################################
        self.centralWidget = QWidget()
        self.setCentralWidget(self.centralWidget)
        self.mainVBOX_param_scene = QVBoxLayout()
        self.mascene = plot(self)


        self.paramPlotV = QVBoxLayout()
        self.horizontalSliders  = QScrollBar(Qt.Horizontal)
        self.horizontalSliders.setFocusPolicy(Qt.StrongFocus)
        self.horizontalSliders.valueChanged.connect(self.update_plot)
        self.horizontalSliders.setMinimum(0)
        self.horizontalSliders.setMaximum(1)


        self.paramPlot = QHBoxLayout()
        l_gain = QLabel('Gain')
        self.e_gain = QLineEdit('5')
        l_win = QLabel('Window')
        self.e_win = QLineEdit('10')
        l_spacing = QLabel('vertical spacing')
        self.e_spacing = QLineEdit('10')
        l_linewidth = QLabel('linewidth')
        self.e_linewidth = QLineEdit('1')

        self.e_gain.returnPressed.connect(self.update_plot)
        self.e_win.returnPressed.connect(self.udpate_plot_plus_slider)
        self.e_spacing.returnPressed.connect(self.update_plot)
        self.e_linewidth.returnPressed.connect(self.update_plot)

        self.paramPlot.addWidget(l_gain)
        self.paramPlot.addWidget(self.e_gain)
        self.paramPlot.addWidget(l_win)
        self.paramPlot.addWidget(self.e_win)
        self.paramPlot.addWidget(l_spacing)
        self.paramPlot.addWidget(self.e_spacing)
        self.paramPlot.addWidget(l_linewidth)
        self.paramPlot.addWidget(self.e_linewidth)

        self.paramPlotV.addWidget(self.horizontalSliders)
        self.paramPlotV.addLayout(self.paramPlot)

        self.mainVBOX_param_scene.addWidget(self.mascene)
        self.mainVBOX_param_scene.addLayout(self.paramPlotV)

        self.centralWidget.setLayout(self.mainVBOX_param_scene)

        self.Fs = 1024
        self.Sigs_dict = np.random.rand(50,20*self.Fs)
        self.t = np.arange(self.Sigs_dict.shape[1])/self.Fs
        self.parent.processEvents()
        self.update()

    def updateslider(self):
        self.horizontalSliders.setMinimum(0)
        self.horizontalSliders.setMaximum(np.ceil(self.t[-1]/int(self.e_win.text()))-1)
        self.horizontalSliders.setPageStep(1)
        self.horizontalSliders.update()

    def udpate_plot_plus_slider(self):
        self.updateslider()
        self.mascene.update()

    def update_plot(self):
        t0 = time.time()
        self.mascene.update()
        print('time old:', time.time()-t0)

    def update(self):
        self.updateslider()
        self.mascene.modify_sigs()
        self.mascene.update()

class plot(QGraphicsView):
    def __init__(self, parent=None):
        super(plot, self).__init__(parent)
        self.parent = parent
        self.scene = QGraphicsScene(self)
        self.setScene(self.scene)
        self.figure = plt.figure(facecolor='white')#Figure()
        self.canvas = FigureCanvas(self.figure)

        self.widget = QWidget()
        self.widget.setLayout(QVBoxLayout())
        self.widget.layout().setContentsMargins(0, 0, 0, 0)
        self.widget.layout().setSpacing(0)
        self.scroll = QScrollArea(self.widget)
        self.scroll.setWidget(self.canvas)

        layout = QVBoxLayout()
        layout.addWidget(self.scroll)
        self.setLayout(layout)

    def modify_sigs(self):
        self.Sigs_dict = self.parent.Sigs_dict
        self.t = self.parent.t
        self.Fs= self.parent.Fs


    def update(self):
        win_num = self.parent.horizontalSliders.value()
        self.figure.clear()
        plt.figure(self.figure.number)
        plt.subplots_adjust(left=0.1, bottom=0.01, right=1, top=1, wspace=0.0 , hspace=0.0 )
        self.axes = plt.subplot(1, 1, 1)
        gain = float(self.parent.e_gain.text())
        win= float(self.parent.e_win.text())
        self.spacing = float(self.parent.e_spacing.text())
        linewidth = float(self.parent.e_linewidth.text())
        ts = int(win*(win_num) * self.Fs)
        te = ts + int(win * self.Fs)
        if te > len(self.t):
            te=len(self.t)
        for i in range(self.Sigs_dict.shape[0]):
            line, = plt.plot(self.t[ts:te], gain*(self.Sigs_dict[i,ts:te]-np.mean(self.Sigs_dict[i,ts:te]))+i*self.spacing, linewidth=linewidth  )


        self.axes.autoscale(enable=True, axis='both', tight=True)
        self.axes.set_ylim((-self.spacing,(self.Sigs_dict.shape[0]+1)*self.spacing))
        self.axes.set_xlim((ts/ self.Fs, ts / self.Fs + win ))

        self.axes.set_yticks(np.arange(self.Sigs_dict.shape[0]) * self.spacing)
        self.axes.set_yticklabels([str(n) for n in np.arange(self.Sigs_dict.shape[0])])



        self.canvas.setGeometry(0, 0, self.parent.width()-100, (self.parent.height()-100)*self.spacing)
        self.canvas.draw()


def main():
    app = QApplication(sys.argv)
    app.setStyle('Windows')
    ex = Viewer(app)
    ex.showMaximized()
    sys.exit(app.exec())


if __name__ == '__main__':
    main()

Answer 1

我将我的 matplotlib 模块的版本从 3.1.1 更新到 3.2.0rc1，它解决了这个问题。

集成在 QScrollArea 中的 Matplotlib 无法在 mac OS 上正确刷新曲线

Matplotlib integrated in a QScrollArea isn't refresh curves properly on mac OS

python

matplotlib

pyqt5

qscrollbar

更新