The black widget lies inside the MainWindow of your application , so as per my understanding when you doubleClick on the black widget you want to maximize the application and if maximized then on double click you want to resize it back.

One option is to subclass QWidget( for your black Widget) and reimplement mouseDoubleClick() function.

Here is a test code :-

MyWidget.h

MyWidget.cpp

Other option is that in your mainwindow you can override eventFilter() function and use installEventFilter() for your widget.

code:-

MainWindow.h

MainWindow.cpp

Sam wrote:

The black widget lies inside the MainWindow of your application , so as per my understanding when you doubleClick on the black widget you want to maximize the application and if maximized then on double click you want to resize it back.

One option is to subclass QWidget( for your black Widget) and reimplement mouseDoubleClick() function.

Here is a test code :-

MyWidget.h

1. class MyWidget : public QWidget
2. {
3.     Q_OBJECT
4. public:
5.     explicit MyWidget(QWidget *parent = 0);
6.  
7.  
8. protected:
9.     void mouseDoubleClickEvent(QMouseEvent *event);
10.  
11. signals:
12.     void doubleClicked();
13. public slots:
14.     void onDoubleClicked();
15.    
16. };

MyWidget.cpp

1. MyWidget::MyWidget(QWidget *parent) :
2.     QWidget(parent)
3. {
4.     connect(this,SIGNAL(doubleClicked()),SLOT(onDoubleClicked()));
5. }
6.  
7. void MyWidget::mouseDoubleClickEvent(QMouseEvent *event)
8. {
9.     emit doubleClicked();
10. }
11.  
12.  
13. void MyWidget::onDoubleClicked()
14. {
15.     if (parentWidget()->isMaximized())
16.     {
17.         // you can implement to move the mainwindow to the center of screen.
18.         qDebug() << parentWidget(); //to see if parentWidget is mainwindow
19.         this->parentWidget()->resize(300,300);
20.  
21.     } else
22.     {
23.         this->parentWidget()->showMaximized();
24.     }
25. }

Other option is that in your mainwindow you can override eventFilter() function and use installEventFilter() for your widget.

code:-

MainWindow.h

1. class MainWindow : public QMainWindow
2. {
3.     Q_OBJECT
4.    
5. public:
6.     explicit MainWindow(QWidget *parent = 0);
7.     ~MainWindow();
8.  
9. public slots:
10.         void onDoubleClicked();
11.  
12. signals:
13.         void doubleClicked();
14.  
15. protected:
16.     void mousePressEvent(QMouseEvent *event);
17.     bool eventFilter(QObject *target, QEvent *event);
18.    
19. private:
20.     Ui::MainWindow *ui;
21.     QWidget *widget;
22.  
23.  
24. };

MainWindow.cpp

@MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow)
{ ui->setupUi(this);

widget = new QWidget(this); widget->installEventFilter(this); widget->setAutoFillBackground(true); widget->setPalette(QPalette(Qt::red)); setCentralWidget(widget); connect(this,SIGNAL),SLOT));

}

MainWindow::~MainWindow()
{ delete ui;
}

void MainWindow::onDoubleClicked()
{ if (isMaximized()) { resize(300,300);

} else { showMaximized(); } }

bool MainWindow::eventFilter(QObject *target, QEvent *event)
{ if (target widget) { if (event->type() QEvent::MouseButtonDblClick) { QMouseEvent *mouseEvent = static_cast<QMouseEvent *>(event); if (mouseEvent->button() == Qt::LeftButton ) { emit doubleClicked(); return QMainWindow::eventFilter(target,event); } } } return QMainWindow::eventFilter(target,event);
}@

NOTE : When doubleclick the black widget ,it should become in full screen mode ,i.e. the full screen of my computer should become black (that is just like a player play video in full screen mode )then if I doubleclick again ,it should return back .

NOTE : When doubleclick the black widget ,it should become in full screen mode ,i.e. the full screen of my computer should become black (that is just like a player play video in full screen mode )then if I doubleclick again ,it should return back .

Thats more easy just set the following for your widget

Sam wrote:

bq. NOTE : When doubleclick the black widget ,it should become in full screen mode ,i.e. the full screen of my computer should become black (that is just like a player play video in full screen mode )then if I doubleclick again ,it should return back .

Thats more easy just set the following for your widget

@setWindowFlags(this->windowFlags() | Qt::CustomizeWindowHint | Qt::WindowStaysOnTopHint | Qt::WindowMaximizeButtonHint | Qt::WindowCloseButtonHint);
setWindowState(this->windowState() | Qt::WindowFullScreen);@

Qt::WindowFullScreen only affects windows,but here the black widget is not window

Are you sure ? coz that works for me , test code :-

Okay here is the complete implementation

MainWindow.h

MainWindow.cpp

This works as required.

redstoneleo wrote:

… http://img.my.csdn.net/uploads/201212/06/1354779576_2592.jpg … http://img.my.csdn.net/uploads/201212/06/1354779928_2090.jpg …

Hi I’m new but interested in this thread. The access to the jpgs is “403 Forbidden” ??!!

bernd

@wartburgritt

Welcome to devnet,

Are you looking for a solution to the problem specified in the first post ?

For the above images you can have a look at image 1 [google.ae] and image 2 [google.ae]