Generally speaking I would discourage this kind of thing as it can be incredibly annoying for the user. Saying that, I have been in a situation where I had no choice so developed the following simple class:
#include <QtGui/QLineEdit>
#include <QtGui/QKeyEvent>
class LineEdit : public QLineEdit
{
Q_OBJECT
public:
LineEdit(QWidget *parent=0) : QLineEdit(parent){ init(); }
LineEdit(const QString &contents, QWidget *parent=0) : QLineEdit(contents,parent){ init(); }
private:
void init(){
setAcceptDrops(false);
setContextMenuPolicy(Qt::CustomContextMenu);
connect(this, SIGNAL(customContextMenuRequested(QPoint)), SLOT(showMenu(QPoint)));
}
protected:
void keyPressEvent(QKeyEvent *event){
if(event->matches(QKeySequence::Copy) || event->matches(QKeySequence::Cut) || event->matches(QKeySequence::Paste))
event->ignore();
else return QLineEdit::keyPressEvent(event);
}
private slots:
void showMenu(QPoint position){}
};
It basically works by:
Catching the "QKeyEvent":http://qt-project.org/doc/qt-4.8/qkeyevent.html for the copy, cut and paste "QKeySequences":http://qt-project.org/doc/qt-4.8/qkeysequence.html and preventing there propagation,
Preventing the user from dragging and dropping data ("setAcceptDrops":http://qt-project.org/doc/qt-4.8/qwidget.html#acceptDrops-prop), and
Redirecting a request for a context menu to a custom slot to prevent the system menu being shown with the cut, copy and paste actions and allowing for the implementation of a custom menu.
Hope this helps ;o)
