Embed a Matplotlib graphic into a widget - PyQt5 - python-3.x

Question

I would like to embed a graphic from Matplotlib into an existing GUI containing a Widget and a PushButton developed from QtDesigner and PyQt5. I can embed the graphic but can't resize the graphic to take all space available/needed into the Widget.
Front end code:
from PyQt5 import QtCore, QtGui, QtWidgets
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(595, 393)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.gridLayout = QtWidgets.QGridLayout(self.centralwidget)
self.gridLayout.setObjectName("gridLayout")
self.pushButton = QtWidgets.QPushButton(self.centralwidget)
self.pushButton.setMaximumSize(QtCore.QSize(100, 16777215))
self.pushButton.setObjectName("pushButton")
self.gridLayout.addWidget(self.pushButton, 0, 0, 1, 1)
self.widget = QtWidgets.QWidget(self.centralwidget)
self.widget.setMinimumSize(QtCore.QSize(0, 200))
self.widget.setStyleSheet("background-color: rgb(255, 255, 255);")
self.widget.setObjectName("widget")
self.gridLayout.addWidget(self.widget, 0, 1, 1, 1)
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 595, 21))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.pushButton.setText(_translate("MainWindow", "PushButton"))
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)
MainWindow.show()
sys.exit(app.exec_())
Back end code:
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QMainWindow, QApplication, QWidget, QSizePolicy
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
from matplotlib.figure import Figure
from front_end import Ui_MainWindow
class Graph_init(FigureCanvas):
def __init__(self, parent=None):
fig = Figure()
self.axes = fig.add_subplot(111)
self.compute_initial_figure()
FigureCanvas.__init__(self, fig)
self.setParent(parent)
FigureCanvas.setSizePolicy(self, QSizePolicy.Expanding, QSizePolicy.Expanding)
FigureCanvas.updateGeometry(self)
class Graph_populate(Graph_init):
def compute_initial_figure(self):
x = [2000,2001,2002,2003,2004]
y = [10,20,30,40,50]
self.axes.plot(x, y)
class GUI(QMainWindow, Ui_MainWindow):
def __init__(self, parent=None):
super(GUI, self).__init__(parent)
self.setupUi(self)
self.sc = Graph_populate(self.widget)
if __name__ == '__main__':
app = QApplication(sys.argv)
prog = GUI()
prog.showMaximized()
sys.exit(app.exec_())
Thank you

Answer 1

In PyQt you would normally add a widget to your application by adding it to a Layout. In the code you seem to have forgotten to do that step.
So if self.gridLayout is the layout you want your FigureCanvas to reside in, you would need to add the latter to the former as
self.gridLayout.addWidget(self.sc, 0, 1, 1, 1)
The role of self.widget on the other hand is not really clear here and you may probably remove it. The self.centralwidget can take the role of the parent, if it is really needed,
self.sc = Graph_populate(self.centralwidget)