How to disable ALT + F4

[elizabeth.h1]

I was looking to find the same , but can't find it.
I am sure there is must some way to say if ALT +F4 was pressed

[elizabeth.h1]

I try the following , but not working :

bool MyDlg::event(QEvent *event)
{
    QKeyEvent* myKeyEvent=(QKeyEvent*)event;
    if(myKeyEvent->matches(QKeySequence::Close))
        return true;
    return QDialog::event(event);
}

bool MyDlg::event(QEvent *event)
{
    QKeyEvent* myKeyEvent=(QKeyEvent*)event;
    if(myKeyEvent->matches(QKeySequence::Close))
        return true;
    return QDialog::event(event);
}

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[kwisp]

see my "crutch" example you can simplify it

#include <QApplication>
#include <QUrl>
#include <QVariant>
#include <QString>
#include <QtGlobal>
#include <QDebug>
#include <QWidget>
#include <QKeyEvent>
#include <QCloseEvent>
#include <QMouseEvent>
#include <QEvent>
 
class CloseHandler:public QObject {
	private:
		bool flag;
	protected:
		bool eventFilter(QObject* obj, QEvent* event)
		{
			if(obj->isWidgetType()) {
				switch(event->type()) {
					case QEvent::Close: {
						qDebug()<<__func__<<"Close";
						if(flag){
							event->ignore();
							return true;
						}
						//flag = false;
						break;
					}
					case QEvent::KeyPress: {
						if(((QKeyEvent*)event)->key() == Qt::Key_F4 || (((QKeyEvent*)event)->modifiers() == Qt::AltModifier)) {
							flag = true;
						}
						break;
					}
					case QEvent::MouseButtonPress://??
					case QEvent::MouseButtonRelease://??
					case QEvent::MouseMove://??
					case QEvent::Leave://!!
						flag = false;
					default: break;
				}
			}
			return QObject::eventFilter(obj,event);
		}
};
 
int main(int a ,char** b )
{
	QApplication app(a,b);
	QWidget w;
	CloseHandler h;
	w.installEventFilter(&h);
	w.show();
	return app.exec();
}

#include <QApplication>
#include <QUrl>
#include <QVariant>
#include <QString>
#include <QtGlobal>
#include <QDebug>
#include <QWidget>
#include <QKeyEvent>
#include <QCloseEvent>
#include <QMouseEvent>
#include <QEvent>

class CloseHandler:public QObject {
	private:
		bool flag;
	protected:
		bool eventFilter(QObject* obj, QEvent* event)
		{
			if(obj->isWidgetType()) {
				switch(event->type()) {
					case QEvent::Close: {
						qDebug()<<__func__<<"Close";
						if(flag){
							event->ignore();
							return true;
						}
						//flag = false;
						break;
					}
					case QEvent::KeyPress: {
						if(((QKeyEvent*)event)->key() == Qt::Key_F4 || (((QKeyEvent*)event)->modifiers() == Qt::AltModifier)) {
							flag = true;
						}
						break;
					}
					case QEvent::MouseButtonPress://??
					case QEvent::MouseButtonRelease://??
					case QEvent::MouseMove://??
					case QEvent::Leave://!!
						flag = false;
					default: break;
				}
			}
			return QObject::eventFilter(obj,event);
		}
};

int main(int a ,char** b )
{
	QApplication app(a,b);
	QWidget w;
	CloseHandler h;
	w.installEventFilter(&h);
	w.show();
	return app.exec();
}

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[wirasto]

How to disable escape key too ? I modified your code, but not work

case QEvent::KeyPress:
{
     if (((QKeyEvent*)event)->key() == Qt::Key_F4 || (((QKeyEvent*)event)->modifiers() == Qt::AltModifier))
     {
        flag = true;
     }
 
	//this is my code
     if (((QKeyEvent*)event)->key() == Qt::Key_Escape) {
         flag =true;
     }
 
     break;
}

case QEvent::KeyPress:
{
     if (((QKeyEvent*)event)->key() == Qt::Key_F4 || (((QKeyEvent*)event)->modifiers() == Qt::AltModifier))
     {
        flag = true;
     }

	//this is my code
     if (((QKeyEvent*)event)->key() == Qt::Key_Escape) {
         flag =true;
     }

     break;
}

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