Pyside QPushButton and matplotlib mix

Question

I am trying to develop a very simple pyside / Qt program using matplotlib. I want the chart to be drawn at the click of a button. So far, I can draw something on the constructor, but I cannot connect the Pyside event with matplotlib. Is there any way to do this?

import sys import platform import numpy as np import PySide from PySide.QtGui import QApplication, QMainWindow, QTextEdit,\ QPushButton, QMessageBox, QWidget, QVBoxLayout from PySide import QtCore __version__ = '0.0.1' import matplotlib matplotlib.use('Qt4Agg') matplotlib.rcParams['backend.qt4']='PySide' from matplotlib.figure import Figure from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas class MainWindow(QMainWindow): def __init__(self, parent=None): super(MainWindow, self).__init__(parent) self.main_frame = QWidget() self.figure = Figure() self.canvas = FigureCanvas(self.figure) self.canvas.setParent( self.main_frame ) self.axes = self.figure.add_subplot(111) vbox = QVBoxLayout( ) vbox.addWidget( self.canvas ) self.main_frame.setLayout( vbox ) self.setCentralWidget( self.main_frame ) self.button = QPushButton('Run') def button_pressed(self): data1 = np.loadtxt('FStream.dat') data2 = np.loadtxt('FShield.dat') self.axes.plot(data1[0],data1[1],data2[0],data2[1]) print 'pressed' self.canvas.draw() if __name__ == '__main__': app = QApplication(sys.argv) frame = MainWindow() frame.button.clicked.connect(frame.button_pressed) frame.button.show() frame.show() app.exec_() 

Thanks a lot!

EDIT: Edited code to put draw ().

EDIT 2: Separation in different functions now looks like this:

 import sys import platform import numpy as np import PySide from PySide.QtGui import QApplication, QMainWindow, QTextEdit,\ QPushButton, QMessageBox, QWidget, QVBoxLayout from PySide import QtCore __version__ = '0.0.1' from ui_pygradient_uni import Ui_MainWindow import matplotlib import widgets.matplotlibwidget matplotlib.use('Qt4Agg') matplotlib.rcParams['backend.qt4']='PySide' #from matplotlib.figure import Figure #from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas class MainWindow(QMainWindow): def __init__(self, parent=None): super(MainWindow, self).__init__(parent) self.main_frame = widgets.matplotlibwidget.MatplotlibWidget() self.button = QPushButton('Run') vbox = QVBoxLayout( ) vbox.addWidget( self.main_frame.canvas ) self.main_frame.setLayout( vbox ) self.setCentralWidget( self.main_frame ) def button_pressed(self): data1 = np.loadtxt('FStream.dat') data2 = np.loadtxt('FShield.dat') self.axes.plot(data1[0],data1[1],data2[0],data2[1]) self.canvas.draw() print 'pressed' if __name__ == '__main__': app = QApplication(sys.argv) frame = MainWindow() frame.button.clicked.connect(frame.main_frame.Plot) frame.button.show() frame.show() app.exec_() 

And matplotlibwidget looks like this:

 import matplotlib import numpy as np matplotlib.use('Qt4Agg') matplotlib.rcParams['backend.qt4']='PySide' from matplotlib.figure import Figure from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas class MatplotlibWidget(FigureCanvas): def __init__(self, parent=None): super(MatplotlibWidget, self).__init__(Figure()) self.setParent(parent) self.figure = Figure() self.canvas = FigureCanvas(self.figure) self.axes = self.figure.add_subplot(111) def Plot(self): data1 = np.loadtxt('FStream.dat') data2 = np.loadtxt('FShield.dat') self.axes.plot(data1[0],data1[1],data2[0],data2[1]) self.canvas.draw() 

Answer 1

Try to enter

 self.canvas.draw() 

after

 self.axes.plot(data1[0],data1[1],data2[0],data2[1]) 

Your GUI code looks fine, and button_pressed is called correctly, but the graph does not redraw.