我正在尝试让一个Qt窗口在按下按钮时在另一个Qt窗口中显示matplotlib图形。我有一个 .py 文件，该文件使用按钮生成该UI，另一个 .py 文件在运行时会打开一个显示图形的QT窗口。
如果我只运行第二个 .py 文件，则显示图表的QT窗口会打开，没问题。
然而，问题是当我通过第一个运行第二个 .py 文件时， pythonw.exe 在我点击按钮运行第二个时崩溃< strong> .py 文件。
以下是代码（一个 .py 文件。如果用户希望查看matplotlib图，则会为用户创建用户界面以点击该按钮）：
import matplotlib
matplotlib.use('Qt4Agg')
import pylab
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure
try:
_fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
def _fromUtf8(s):
return s
try:
_encoding = QtGui.QApplication.UnicodeUTF8
def _translate(context, text, disambig):
return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
def _translate(context, text, disambig):
return QtGui.QApplication.translate(context, text, disambig)
import matplotlibtest
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName(_fromUtf8("MainWindow"))
MainWindow.resize(690, 786)
self.centralwidget = QtGui.QWidget(MainWindow)
self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
self.widget_2 = QtGui.QWidget(self.centralwidget)
self.widget_2.setGeometry(QtCore.QRect(120, 20, 471, 51))
self.widget_2.setObjectName(_fromUtf8("widget_2"))
#...some other irrelevant code...
self.plotButton = QtGui.QPushButton(self.layoutWidget_2)
self.plotButton.setMinimumSize(QtCore.QSize(0, 23))
self.plotButton.setObjectName(_fromUtf8("plotButton"))
self.gridLayout_2.addWidget(self.plotButton, 9, 1, 1, 1)
self.plotButton.clicked.connect(self.showimage)
def showimage(self):
matplotlibtest.main()
因此，当用户点击 plotButton 时，会运行 matplotlibtest.py 的主要功能。
在 matplotlibtest.py 中，我有这段代码（来自http://packtlib.packtpub.com/library/9781847197900/ch06）。运行时此代码打开一个QT窗口，显示一个简单的matplotlib图。这里没有问题 - 当运行此代码时，它会按照我的意愿打开图形。
# for command-line arguments
import sys
# Python Qt4 bindings for GUI objects
from PyQt4 import QtGui
# Numpy functions for image creation
import numpy as np
# Matplotlib Figure object
from matplotlib.figure import Figure
import matplotlib
matplotlib.use('Qt4Agg')
# import the Qt4Agg FigureCanvas object, that binds Figure to
# Qt4Agg backend. It also inherits from QWidget
from matplotlib.backends.backend_qt4agg \
import FigureCanvasQTAgg as FigureCanvas
# import the NavigationToolbar Qt4Agg widget
from matplotlib.backends.backend_qt4agg \
import NavigationToolbar2QTAgg as NavigationToolbar
class Qt4MplCanvas(FigureCanvas):
def __init__(self, parent):
# plot definition
self.fig = Figure()
self.axes = self.fig.add_subplot(111)
t = np.arange(0.0, 3.0, 0.01)
s = np.cos(2*np.pi*t)
self.axes.plot(t, s)
# initialization of the canvas
FigureCanvas.__init__(self, self.fig)
# set the parent widget
self.setParent(parent)
# we define the widget as expandable
FigureCanvas.setSizePolicy(self,
QtGui.QSizePolicy.Expanding,
QtGui.QSizePolicy.Expanding)
# notify the system of updated policy
FigureCanvas.updateGeometry(self)
class ApplicationWindow(QtGui.QMainWindow):
def __init__(self):
# initialization of Qt MainWindow widget
QtGui.QMainWindow.__init__(self)
# set window title
self.setWindowTitle("Matplotlib Figure in a Qt4 Window With NavigationToolbar")
# instantiate a widget, it will be the main one
self.main_widget = QtGui.QWidget(self)
# create a vertical box layout widget
vbl = QtGui.QVBoxLayout(self.main_widget)
# instantiate our Matplotlib canvas widget
qmc = Qt4MplCanvas(self.main_widget)
# instantiate the navigation toolbar
ntb = NavigationToolbar(qmc, self.main_widget)
# pack these widget into the vertical box
vbl.addWidget(qmc)
vbl.addWidget(ntb)
# set the focus on the main widget
self.main_widget.setFocus()
# set the central widget of MainWindow to main_widget
self.setCentralWidget(self.main_widget)
def main():
# create the GUI application
qApp = QtGui.QApplication(sys.argv)
# instantiate the ApplicationWindow widget
aw = ApplicationWindow()
# show the widget
aw.show()
sys.exit(qApp.exec_())
if __name__ == '__main__':
main()
单击按钮时如何显示matplotlib图？
为什么 pythonw.exe 崩溃？
如果我想传递参数（x = [1,2,3]，y = [1,1,1]）来制作图表，我会放class Qt4MplCanvas(FigureCanvas): def __init__(self,parent,x,y)，当我构建它时我写qmc = Qt4MplCanvas(self.main_widget, [1,2,3], [1,1,1])？
在任何Qt对象的__init__中，我们是否运行超级__init__来初始化Qt对象的父对象？
为什么super(MyMainWindow,self)的参数？
为什么我们使用'对象'
class Ui_MainWIndow(object):
但我们使用'QtGui.QMainWindow'
class MyMainWindow(QtGui.QMainWindow)？
是'object'和'QtGui.QMainWindow'的论点吗？
当我们构建一个Ui_MainWindow时，我们为什么要写
self.ui = Ui_MainWindow()
并不是
self.ui = Ui_MainWindow(object)？
答案 0 :(得分：1)
好的，你的代码中有几个问题：
Ui定义对象，但您没有使用它。matplotlib.use（一个在主.py中，另一个在matplotlibtest中）PyQt应用程序，则必须创建QApplication对象对于解决方案，请检查代码，这是我对您的代码所做的一些修改，以使其工作：
在 .py主文件：
中from PyQt4 import QtCore,QtGui
try:
_fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
def _fromUtf8(s):
return s
try:
_encoding = QtGui.QApplication.UnicodeUTF8
def _translate(context, text, disambig):
return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
def _translate(context, text, disambig):
return QtGui.QApplication.translate(context, text, disambig)
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName(_fromUtf8("MainWindow"))
MainWindow.resize(690, 786)
self.centralwidget = QtGui.QWidget(MainWindow)
self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
self.gridLayout_2 = QtGui.QGridLayout(self.centralwidget) #here
self.centralwidget.setLayout(self.gridLayout_2) #here
#...some other irrelevant code...
self.plotButton = QtGui.QPushButton() #here
self.plotButton.setMinimumSize(QtCore.QSize(0, 23))
self.plotButton.setObjectName(_fromUtf8("plotButton"))
self.gridLayout_2.addWidget(self.plotButton, 9, 1, 1, 1)
self.plotButton.clicked.connect(self.showimage)
def showimage(self):
#changes here
from matplotlibtest import ApplicationWindow
self.aw = ApplicationWindow()
self.aw.show()
#class that actually shows something
class MyMainWindow(QtGui.QMainWindow):
def __init__(self,parent=None):
super(MyMainWindow,self).__init__()
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
#put the main window here
def main():
import sys
qApp = QtGui.QApplication(sys.argv)
aw = MyMainWindow()
aw.show()
sys.exit(qApp.exec_())
if __name__ == '__main__':
main()
在 matplotlibtest.py ：
# Python Qt4 bindings for GUI objects
from PyQt4 import QtGui
# Numpy functions for image creation
import numpy as np
# Matplotlib Figure object
from matplotlib.figure import Figure
import matplotlib
matplotlib.use('Qt4Agg')
# import the Qt4Agg FigureCanvas object, that binds Figure to
# Qt4Agg backend. It also inherits from QWidget
from matplotlib.backends.backend_qt4agg \
import FigureCanvasQTAgg as FigureCanvas
# import the NavigationToolbar Qt4Agg widget
from matplotlib.backends.backend_qt4agg \
import NavigationToolbar2QTAgg as NavigationToolbar
class Qt4MplCanvas(FigureCanvas):
def __init__(self, parent):
# plot definition
self.fig = Figure()
self.axes = self.fig.add_subplot(111)
t = np.arange(0.0, 3.0, 0.01)
s = np.cos(2*np.pi*t)
self.axes.plot(t, s)
# initialization of the canvas
FigureCanvas.__init__(self, self.fig)
# set the parent widget
self.setParent(parent)
# we define the widget as expandable
FigureCanvas.setSizePolicy(self,
QtGui.QSizePolicy.Expanding,
QtGui.QSizePolicy.Expanding)
# notify the system of updated policy
FigureCanvas.updateGeometry(self)
class ApplicationWindow(QtGui.QMainWindow):
def __init__(self):
# initialization of Qt MainWindow widget
QtGui.QMainWindow.__init__(self)
# set window title
self.setWindowTitle("Matplotlib Figure in a Qt4 Window With NavigationToolbar")
# instantiate a widget, it will be the main one
self.main_widget = QtGui.QWidget(self)
# create a vertical box layout widget
vbl = QtGui.QVBoxLayout(self.main_widget)
# instantiate our Matplotlib canvas widget
qmc = Qt4MplCanvas(self.main_widget)
# instantiate the navigation toolbar
ntb = NavigationToolbar(qmc, self.main_widget)
# pack these widget into the vertical box
vbl.addWidget(qmc)
vbl.addWidget(ntb)
# set the focus on the main widget
self.main_widget.setFocus()
# set the central widget of MainWindow to main_widget
self.setCentralWidget(self.main_widget)
#deleted the main function here