python - 在 python 代码中与使用 Qt Designer 创建的 MatplotlibWidget 交互

Question

我在与通过 Qt Designer 创建的 MatplotlibWidget 交互时遇到问题。我无法更改轴标签、比例、提供标题或任何内容。我做错了什么吗？

这是使用 Qt Designer 生成的示例 UI 代码:

from PyQt4 import QtCore, QtGui

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.mplwidget = MatplotlibWidget(self.centralwidget)

        self.mplwidget.setGeometry(QtCore.QRect(70, 50, 400, 300))
        self.mplwidget.setObjectName("mplwidget")

        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtGui.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 21))
        self.menubar.setObjectName("menubar")
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtGui.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

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

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(QtGui.QApplication.translate("MainWindow", "MainWindow", None, QtGui.QApplication.UnicodeUTF8))

from matplotlibwidget import MatplotlibWidget

class MainWindow(QtGui.QMainWindow, Ui_MainWindow):

    def __init__(self, parent=None, f=QtCore.Qt.WindowFlags()):
        QtGui.QMainWindow.__init__(self, parent, f)

        self.setupUi(self)

这是我编写的用于与 UI python 代码交互的 python 代码:

from PyQt4 import QtGui, QtCore
from TestUI2 import MainWindow

class Window(MainWindow):
    def __init__(self):
        MainWindow.__init__(self)

        x=[0,10,100]
        y=[3,4,5]

        self.mplwidget.axes.set_xscale('log') # Nothing Happens 
        self.mplwidget.axes.set_title('GRAPH') # Nothing Happens

        self.mplwidget.axes.plot(x,y) 


if __name__ == '__main__':

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

Answer 1

您需要先为 MatplotlibWidget 定义您自己的类(在您的主脚本中，而不是 UI 代码中)，然后在 Window() 定义中实例化它。为此，您还需要从 _qt4agg matplotlib 后端模块和 Figure 类导入 FigureCanvas:

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as Canvas
from matplotlib.figure import Figure

然后在 Matplotlib 类定义中创建 Figure 子图和 Figure Canvas 的实例，然后可以使用它们与主窗口中的图进行交互。所以使用你的代码看起来像这样:

from PyQt4 import QtGui, QtCore
from TestUI2 import MainWindow

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as Canvas
from matplotlib.figure import Figure

class Window(MainWindow):
    def __init__(self):
        MainWindow.__init__(self)

        x=[0,10,100]
        y=[3,4,5]

        self.mplwidget = MatplotlibWidget(self.centralwidget)

        self.mplwidget.setGeometry(QtCore.QRect(70, 50, 600, 500))
        self.mplwidget.setObjectName("mplwidget")

        self.mplwidget.plotDataPoints(x,y)    

class MatplotlibWidget(Canvas):        
    def __init__(self, parent=None, title='Title', xlabel='x label', ylabel='y label', dpi=100, hold=False):
        super(MatplotlibWidget, self).__init__(Figure())

        self.setParent(parent)
        self.figure = Figure(dpi=dpi)
        self.canvas = Canvas(self.figure)
        self.theplot = self.figure.add_subplot(111)        

        self.theplot.set_title(title)
        self.theplot.set_xlabel(xlabel)
        self.theplot.set_ylabel(ylabel)

    def plotDataPoints(self, x, y):
        self.theplot.plot(x,y)
        self.draw()            

if __name__ == '__main__':

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

和 Ui 脚本:

from PyQt4 import QtCore, QtGui

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)

        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")        

        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtGui.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 21))
        self.menubar.setObjectName("menubar")
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtGui.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

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

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(QtGui.QApplication.translate("MainWindow", "MainWindow", None, QtGui.QApplication.UnicodeUTF8))

class MainWindow(QtGui.QMainWindow, Ui_MainWindow):

    def __init__(self, parent=None, f=QtCore.Qt.WindowFlags()):
        QtGui.QMainWindow.__init__(self, parent, f)

        self.setupUi(self)

然后，如果您想与 mpl 图交互，例如更改标题，您可以在 Window 类中进行操作，例如:

self.mplwidget.theplot.set_title("New Title")

希望对您有所帮助。