title: Detect resizing in Widget-window resized signal
body: <p>I create a simple UI with Qt Designer and convert it to Python codes. I searched for any method to detect changing window size.</p>
  
  <p>This is the generated code :</p>
  
  <pre><code>from PyQt5 import QtCore, QtGui, QtWidgets
  
  class Ui_MainWindow(object):
      def onResize(event):
          print(event)
  
      def setupUi(self, MainWindow):
          MainWindow.setObjectName("MainWindow")
          MainWindow.setWindowTitle("MainWindow")
          MainWindow.resize(200, 200)
          self.centralwidget = QtWidgets.QWidget(MainWindow)
          self.centralwidget.setObjectName("centralwidget")
          MainWindow.setCentralWidget(self.centralwidget)
  
          MainWindow.resized.connect(self.someFunction)
  
          QtCore.QMetaObject.connectSlotsByName(MainWindow)
  
  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_())
  </code></pre>
  
  <p>I found a similar question <a href="https://stackoverflow.com/questions/8955780/qwidget-resize-signal">QWidget resize signal?</a> and <a href="http://codeprogress.com/python/libraries/pyqt/showPyQTExample.php?index=360&amp;key=QMainWindowResizeEvent" rel="noreferrer">this tutorial to handle size</a> that recommended overriding <em>resizeEvent</em> method of <em>QMainWindow</em>.</p>
  
  <p>But any of them doesn't solve my problem. Is there any <strong>resized</strong> function to detect window resizing like below:</p>
  
  <pre><code>MainWindow.resized.connect(self.someFunction)
  </code></pre>