here my kode where I generated event for QLineEdit to put pressed key combination in textline it Ok for Shift key and Alt key but not for Ctrl key why ?
#!/usr/bin/python
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
def main():
app = QApplication(sys.argv)
w = MyWindow()
w.show()
sys.exit(app.exec_())
class MyWindow(QWidget):
def __init__(self, *args):
QWidget.__init__(self, *args)
self.la = QLabel("Press tab in this box:")
self.le = MyLineEdit()
layout = QVBoxLayout()
layout.addWidget(self.la)
layout.addWidget(self.le)
self.setLayout(layout)
self.connect(self.le, SIGNAL("press"),
self.update)
def update(self):
oldText = str(self.le.text())
self.le.setText(self.le.myText)
class MyLineEdit(QLineEdit):
def __init__(self, *args):
QLineEdit.__init__(self, *args)
self.myText = ""
def event(self, event):
if event.type() == QEvent.KeyPress:
if event.modifiers() & Qt.ControlModifier :
in textline it is Ok for Shift key and Alt key I can put by variable self.myText value in textline, but not for Ctrl key why ?
print event.text()
self.myText = "Ctrl+"+ event.text()
self.emit(SIGNAL("press"))
return True
return QLineEdit.event(self, event)
if __name__ == "__main__":
main()
The reason why the original example doesn't work is because many of the Ctrl+key combinations produce control characters - e.g. Ctrl+J produces a newline.
The correct way to capture keyboard combinations is using QKeySequence, which will work for all keys, including function keys, arrow keys, page up/down keys, etc. You can also get translated shortcuts by using QKeySequence.PortableText.
Here's a demo based on the original example:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
def main():
app = QApplication(sys.argv)
w = MyWindow()
w.show()
sys.exit(app.exec_())
class MyWindow(QWidget):
def __init__(self, *args):
QWidget.__init__(self, *args)
self.la = QLabel("Press tab in this box:")
self.le = MyLineEdit()
layout = QVBoxLayout()
layout.addWidget(self.la)
layout.addWidget(self.le)
self.setLayout(layout)
self.le.keyPressed.connect(self.update)
def update(self, text):
self.le.setText(text)
MOD_MASK = (Qt.CTRL | Qt.ALT | Qt.SHIFT | Qt.META)
class MyLineEdit(QLineEdit):
keyPressed = pyqtSignal(str)
def keyPressEvent(self, event):
keyname = ''
key = event.key()
modifiers = int(event.modifiers())
if (modifiers and modifiers & MOD_MASK == modifiers and
key > 0 and key != Qt.Key_Shift and key != Qt.Key_Alt and
key != Qt.Key_Control and key != Qt.Key_Meta):
keyname = QKeySequence(modifiers + key).toString()
print('event.text(): %r' % event.text())
print('event.key(): %d, %#x, %s' % (key, key, keyname))
self.keyPressed.emit(keyname)
if __name__ == "__main__":
main()