How can I check if a keyboard modifier is pressed (Shift, Ctrl, or Alt)?

Question

I am building a UI with Qt Creator and I want buttons to perform different actions with different modifiers. So I thought I could call functions with dynamic string properties that would perform the action depending on the modifier.

Is there a simpler way to do this?

Answer 1

It looks like all you need to do is check the keyboardModifiers in your button handler, and select a different action as appropriate. The various modifiers can be OR'd together in order to check for multi-key combinations:

PyQt5:

import sys from PyQt5 import QtCore, QtWidgets  class Window(QtWidgets.QWidget):     def __init__(self):         super().__init__()         self.button = QtWidgets.QPushButton('Test')         self.button.clicked.connect(self.handleButton)         layout = QtWidgets.QVBoxLayout(self)         layout.addWidget(self.button)      def handleButton(self):         modifiers = QtWidgets.QApplication.keyboardModifiers()         if modifiers == QtCore.Qt.ShiftModifier:             print('Shift+Click')         elif modifiers == QtCore.Qt.ControlModifier:             print('Control+Click')         elif modifiers == (QtCore.Qt.ControlModifier |                            QtCore.Qt.ShiftModifier):             print('Control+Shift+Click')         else:             print('Click')  if __name__ == '__main__':      app = QtWidgets.QApplication(sys.argv)     window = Window()     window.show()     sys.exit(app.exec()) 

PyQt4:

import sys from PyQt4 import QtGui, QtCore  class Window(QtGui.QWidget):     def __init__(self):         super(Window, self).__init__()         self.button = QtGui.QPushButton('Test')         self.button.clicked.connect(self.handleButton)         layout = QtGui.QVBoxLayout(self)         layout.addWidget(self.button)      def handleButton(self):         modifiers = QtGui.QApplication.keyboardModifiers()         if modifiers == QtCore.Qt.ShiftModifier:             print('Shift+Click')         elif modifiers == QtCore.Qt.ControlModifier:             print('Control+Click')         elif modifiers == (QtCore.Qt.ControlModifier |                            QtCore.Qt.ShiftModifier):             print('Control+Shift+Click')         else:             print('Click')  if __name__ == '__main__':      app = QtGui.QApplication(sys.argv)     window = Window()     window.show()     sys.exit(app.exec_()) 

Answer 2

I was trying to handle multiple keys pressed at the same time (e.g. A and W or W and D). The solution below works with multiple keys being pressed at the same time (including Ctrl, Shift, Alt, etc.).

def keyPressEvent(self, event):     self.firstrelease = True     astr = "pressed: " + str(event.key())     self.keylist.append(astr)  def keyReleaseEvent(self, event):     if self.firstrelease == True:         self.processmultikeys(self.keylist)      self.firstrelease = False     del self.keylist[-1]  def processmultikeys(self, keyspressed):     # Your logic here     print keyspressed 

Go here for the original discussion of this solution: How to get multiple key presses in single event?