Matplotlib 2.1.0 导航工具栏中的主页按钮嵌入在 pyqt5 窗口中，它不再正常工作

Question

我在 qtdesigner pyqt5 制作的窗口中嵌入了一个 matplotlib。我有 3 个文件

窗口：

from PyQt5 import QtCore, QtGui, QtWidgets

class Ui_MplMainWindow(object):
    def setupUi(self, MplMainWindow):
        MplMainWindow.setObjectName("MplMainWindow")
        MplMainWindow.resize(628, 416)
        self.centralwidget = QtWidgets.QWidget(MplMainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.gridLayout_2 = QtWidgets.QGridLayout(self.centralwidget)
        self.gridLayout_2.setObjectName("gridLayout_2")
        self.mpl = MplWidgetTest(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.mpl.sizePolicy().hasHeightForWidth())
        self.mpl.setSizePolicy(sizePolicy)
        self.mpl.setObjectName("mpl")
        self.gridLayout_2.addWidget(self.mpl, 0, 0, 1, 1)
        self.groupBox = QtWidgets.QGroupBox(self.centralwidget)
        self.groupBox.setMaximumSize(QtCore.QSize(95, 16777215))
        self.groupBox.setObjectName("groupBox")
        self.gridLayout = QtWidgets.QGridLayout(self.groupBox)
        self.gridLayout.setObjectName("gridLayout")
        self.buttonDrawDate = QtWidgets.QPushButton(self.groupBox)
        self.buttonDrawDate.setMaximumSize(QtCore.QSize(75, 16777215))
        self.buttonDrawDate.setObjectName("buttonDrawDate")
        self.gridLayout.addWidget(self.buttonDrawDate, 0, 0, 1, 1)
        self.buttonErase = QtWidgets.QPushButton(self.groupBox)
        self.buttonErase.setMaximumSize(QtCore.QSize(75, 16777215))
        self.buttonErase.setObjectName("buttonErase")
        self.gridLayout.addWidget(self.buttonErase, 1, 0, 1, 1)
        spacerItem = QtWidgets.QSpacerItem(20, 40, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
        self.gridLayout.addItem(spacerItem, 2, 0, 1, 1)
        self.gridLayout_2.addWidget(self.groupBox, 0, 1, 1, 1)
        MplMainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(MplMainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 628, 21))
        self.menubar.setObjectName("menubar")
        MplMainWindow.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(MplMainWindow)
        self.statusbar.setObjectName("statusbar")
        MplMainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MplMainWindow)
        QtCore.QMetaObject.connectSlotsByName(MplMainWindow)

    def retranslateUi(self, MplMainWindow):
        _translate = QtCore.QCoreApplication.translate
        MplMainWindow.setWindowTitle(_translate("MplMainWindow", "MainWindow"))
        self.groupBox.setTitle(_translate("MplMainWindow", "GroupBox"))
        self.buttonDrawDate.setText(_translate("MplMainWindow", "Draw"))
        self.buttonErase.setText(_translate("MplMainWindow", "Erase"))

from mplwidgettest import MplWidgetTest

Matplot 小部件类：

from PyQt5.QtWidgets import QSizePolicy, QWidget, QVBoxLayout
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt5agg import (
    FigureCanvasQTAgg as FigureCanvas,
    NavigationToolbar2QT as NavigationToolbar)


class MplCanvas(FigureCanvas):
    """Class to represent the FigureCanvas widget"""
    def __init__(self):
        # setup Matplotlib Figure and Axis
        self.fig = Figure()
        self.ax = self.fig.add_subplot(111)
        # initialization of the canvas
        FigureCanvas.__init__(self, self.fig)
        # we define the widget as expandable
        FigureCanvas.setSizePolicy(self,
                                   QSizePolicy.Expanding,
                                   QSizePolicy.Expanding)
        # notify the system of updated policy
        FigureCanvas.updateGeometry(self)
class MplWidgetTest(QWidget):
    """Widget defined in Qt Designer"""
    def __init__(self, parent = None):
        # initialization of Qt MainWindow widget
        QWidget.__init__(self, parent)
        # set the canvas to the Matplotlib widget
        self.canvas = MplCanvas()
        # create a NavigatioToolbar
        self.ntb=NavigationToolbar(self.canvas,self)
        # create a vertical box layout
        self.vbl = QVBoxLayout()
        # add mpl widget to vertical box
        self.vbl.addWidget(self.canvas)
        # add NavigationToolBar to vertical box
        self.vbl.addWidget(self.ntb)
        # set the layout to th vertical box
        self.setLayout(self.vbl)

以及调用别人的主文件：

import sys
from IHMDrawDates import Ui_MplMainWindow
from PyQt5.QtWidgets import QMainWindow, QApplication, QWidget
import numpy as np
import datetime


class DesignerMainWindow(QMainWindow, Ui_MplMainWindow):
    def __init__(self, parent = None):
        super(DesignerMainWindow, self).__init__(parent)
        self.setupUi(self)
        # connect the signals with the slots
        self.buttonDrawDate.clicked.connect(self.drawDate)
        self.buttonErase.clicked.connect(self.eraseDate)
    def drawDate(self):
#        base = datetime.datetime(2018, 1, 1)
#        x = np.array([base + datetime.timedelta(hours=i) for i in range(24)])
#        y = np.random.rand(len(x))
        x = np.arange(0,100,0.1)
        y = np.sin(x)
        self.mpl.canvas.ax.plot(x,y)
        self.mpl.canvas.ax.relim()
        self.mpl.canvas.ax.autoscale(True)
        self.mpl.canvas.draw()
    def eraseDate(self):
        self.mpl.canvas.ax.clear()
        self.mpl.canvas.draw()


if __name__ == '__main__':
    app=0
    app = QApplication(sys.argv)
    dmw = DesignerMainWindow()
    # show it
    dmw.show() 
    sys.exit(app.exec_())    

更新到 matplotlib 2.1.0 后，主页按钮无法正常工作。它总是返回到最初的干净轴。示例：

1.-点击绘图按钮前：

2.-点击绘图按钮：

3.-点击放大：

4.-点击首页：

在更新之前，按下 HOME 按钮返回到图像编号 2，现在使用 matplotlib 2.1.0 它返回到图像 4。任何想法。

当我添加时：

def drawDate(self):
    x = np.arange(0,100,0.1)
    y = np.sin(x)
    self.mpl.canvas.ax.plot(x,y)
    self.mpl.canvas.ax.relim()
    self.mpl.canvas.ax.autoscale(True)
    self.mpl.ntb.update()
    self.mpl.canvas.draw()

def eraseDate(self):
    self.mpl.canvas.ax.clear()
    self.mpl.ntb.update()
    self.mpl.canvas.draw()

然后发生：

Answer 1

我猜这个问题的答案已经在这篇文章中给出，只是针对 Tkinter，而不是 PyQt： NagivationToolbar fails when updating in Tkinter canvas

主页按钮恢复绘图的初始状态，这通常是主页按钮所需的功能。

在这里，您显然希望它在单击按钮后恢复绘图状态。这将通过调用工具栏的update() 方法来完成。

在这种情况下，您将添加

self.mpl.ntb.update()

在drawDate 方法中。

该方法可能看起来像

def drawDate(self):
    x = np.arange(0,100,0.1)
    y = np.sin(x)
    self.mpl.canvas.ax.plot(x,y)
    self.mpl.canvas.ax.relim()
    self.mpl.canvas.ax.autoscale(True)
    self.mpl.ntb.update()             # <-- add this
    #self.mpl.ntb.push_current()      #     and possibly this(?)
    self.mpl.canvas.draw()


def eraseDate(self):
    self.mpl.canvas.ax.clear()
    self.mpl.ntb.update()             # <-- add this
    #self.mpl.ntb.push_current()      #     and possibly this(?)
    self.mpl.canvas.draw()