Redirect keyboard events to QTextEdit when it has no focus ?

redstoneleo

when the QTextEdit doesn’t have focus ,how to redirect keyboard events to the text editor ?

@
import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
class BoxLayout(QWidget):
def init(self, parent=None):
super(BoxLayout, self).init(parent)

self.resize(100, 300)

    ok = QPushButton("OK")
    cancel = QPushButton("Cancel")
    self.textEdit = QTextEdit()
    vbox = QVBoxLayout()
    vbox.addWidget(self.textEdit)
    vbox.addWidget(ok)
    vbox.addWidget(cancel)
    self.setLayout(vbox)

app = QApplication(sys.argv)
qb = BoxLayout()
qb.show()
sys.exit(app.exec_())

@

Adrien Leravat

Hi redstoneleo,

(explained using the C++ prototypes)
To receive keyboard events on your QTextEdit, you can

Give it the focus after creating it :
@QWidget::setFocus(Qt::OtherFocusReason)
@
Redirect focus from one widget to another (lets say windows to your edit)
@QWidget::setFocusProcus(QWidget*)
myWindow->setFocusProxy(myTextEdit);
@
Prevent other widgets from gaining focus using
@QWidget::setFocusPolicy(Qt::NoFocus)
@

Or if you need to intercept any key event at application level, you can create an QObject class: reimplement the method
@bool QObject::eventFilter(QObject*, QEvent*)
@

And use QObject::installEventFilter(QObject*) with this class as parameter, on the window, or the application.

redstoneleo

[quote author="Adrien Leravat" date="1374482323"]Hi redstoneleo,

(explained using the C++ prototypes)
To receive keyboard events on your QTextEdit, you can

Give it the focus after creating it :
@QWidget::setFocus(Qt::OtherFocusReason)
@
Redirect focus from one widget to another (lets say windows to your edit)
@QWidget::setFocusProcus(QWidget*)
myWindow->setFocusProxy(myTextEdit);
@
Prevent other widgets from gaining focus using
@QWidget::setFocusPolicy(Qt::NoFocus)
@

Or if you need to intercept any key event at application level, you can create an QObject class: reimplement the method
@bool QObject::eventFilter(QObject*, QEvent*)
@

And use QObject::installEventFilter(QObject*) with this class as parameter, on the window, or the application.[/quote]

thanks for your help !
yes ,I did want to intercept any key event at application level, I have also been told to use event filter at such case before ,but I have difficulty in implementing the eventFilter() function here ,can you show some code ?thanks in advance !

redstoneleo

the following is my code of using Event Filters ,but it doesn't work , anyone can help ?
@
import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
class BoxLayout(QWidget):
def init(self, parent=None):
super(BoxLayout, self).init(parent)
self.resize(100, 300)

    ok = QPushButton("OK")
    cancel = QPushButton("Cancel")
    self.textEdit =QLineEdit("""This function returns true if the contents of the MIME data object, specified by source , can be decoded and inserted into the document. It is called for example when during a drag operation the mouse enters this widget and it is necessary to determine whether it is possible to accept the drag and drop operation.""")
    
    vbox = QVBoxLayout()
    vbox.addWidget(self.textEdit)
    vbox.addWidget(ok)
    vbox.addWidget(cancel)
    self.setLayout(vbox)


    self.textEdit.installEventFilter(self)

def eventFilter(self, obj, event):
    if obj == self and event.type() == QKeyEvent:
            self.textEdit.setFocus () 
            self.textEdit.keyPressEvent(event)
            return True
    else:
        return QMainWindow.eventFilter(self, obj, event)

app = QApplication(sys.argv)
qb = BoxLayout()
qb.show()
sys.exit(app.exec_())

@

raven-worx

you need to install the eventfilter on the QApplication instance ;)

redstoneleo

[quote author="raven-worx" date="1374845629"]you need to install the eventfilter on the QApplication instance ;)[/quote]

if I install the eventfilter on the QApplication instance ,so what should be modified in the eventfilter function ?
this question has stuck me for a few days , I wonder if you could help ,thanks in advance !!!

butterface

Where did you do that? As far as I can tell you installed it on the textEdit.