title: buttons and label does not resize when going to full screen in pyqt5
body: <p>I have created a GUI that has three buttons and a label. But when I go full screen the buttons and the label does not go to full screen even if i am using show full screen. Here is my code.</p>
  <pre><code>class App(object):
      def setupUi(self, Dialog):
          Dialog.setObjectName(&quot;Dialog&quot;)
          Dialog.resize(1500, 617)
          self.processedImgLabel = QtWidgets.QLabel(Dialog)
          self.processedImgLabel.setGeometry(QtCore.QRect(50, 70, 1420, 520))
          self.processedImgLabel.setFrameShape(QtWidgets.QFrame.Box)
          self.processedImgLabel.setText(&quot;&quot;)
          self.processedImgLabel.setObjectName(&quot;processedImgLabel&quot;)
          self.processedImgLabel.showFullScreen()
          self.widget = QtWidgets.QWidget(Dialog)
          self.widget.setGeometry(QtCore.QRect(50, 10, 1291, 25))
          self.widget.setObjectName(&quot;widget&quot;)
          self.horizontalLayout = QtWidgets.QHBoxLayout(self.widget)
          self.horizontalLayout.setContentsMargins(0, 0, 0, 0)
          self.horizontalLayout.setObjectName(&quot;horizontalLayout&quot;)
          self.startButton = QtWidgets.QPushButton(self.widget)
          self.startButton.setObjectName(&quot;startButton&quot;)
          self.horizontalLayout.addWidget(self.startButton)
          self.stopButton = QtWidgets.QPushButton(self.widget)
          self.stopButton.setObjectName(&quot;stopButton&quot;)
          self.horizontalLayout.addWidget(self.stopButton)
          self.detectButton = QtWidgets.QPushButton(self.widget)
          self.detectButton.setObjectName(&quot;detectButton&quot;)
          self.comboBox = QtWidgets.QComboBox()
          self.comboBox.setObjectName(&quot;comboBox&quot;)
          self.horizontalLayout.addWidget(self.detectButton)
  
          self.retranslateUi(Dialog)
          QtCore.QMetaObject.connectSlotsByName(Dialog)
          
  
      def retranslateUi(self, Dialog):
          _translate = QtCore.QCoreApplication.translate
          Dialog.setWindowTitle(_translate(&quot;Dialog&quot;, &quot;App&quot;))
          self.startButton.setText(_translate(&quot;Dialog&quot;, &quot;Start&quot;))
          self.stopButton.setText(_translate(&quot;Dialog&quot;, &quot;Stop&quot;))
          self.detectButton.setText(_translate(&quot;Dialog&quot;, &quot;Exit&quot;))
  </code></pre>
  <p>Here is what is happening:
  Before full screen.
  <a href="https://i.stack.imgur.com/zLuYl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zLuYl.png" alt="enter image description here" /></a></p>
  <p>After full screen
  <a href="https://i.stack.imgur.com/whm1f.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/whm1f.png" alt="enter image description here" /></a></p>