Qt: Force child window to have its own task bar entry

Question

I'm using Qt 5 and C++ and I want to force some of my child windows to have their own task bar entries. Right now, I am able to create parentless QWidgets and use the signal-slot mechanism to close those windows when a main window (QMainWindow) is closed.

However as I add more and more parents and childs this whole signal-slot technique will get tedious (won't it?) and I am sure that Qt already has a feature I can use for this. I've seen this; Primary and Secondary Windows section talks about what I'm trying to do. It says:

In addition, a QWidget that has a parent can become a window by setting the Qt::Window flag. Depending on the window management system such secondary windows are usually stacked on top of their respective parent window, and not have a task bar entry of their own.

I can see that I need to set my QWidgets as Primary Windows but I don't exactly know how.

So I tried:

// when a QMainWindow's (this) push button is clicked:
QWidget* newWindow = new QWidget(this, Qt::Window);
newWindow->show();

It doesn't give me the behavior I want. How can I set newWindow as a Primary Window while still keeping this as its parent?

Answer 1

I don't now native method to do it in Qt. But you can use for it signal/slot it's definitely not create a serious burden on the processor until you have at least a thousand windows. For it you can implement your own child parent mechanizme.

For example:

class myOwnWidget: public QWidget{
    Q_OBJECT
public:
    myOwnWidget(myOwnWidget* parent = 0):
        QWidget(){
        if(parent){
            connect(parent,SIGNAL(close()), this,SLOT(deleteLater()));
        }
    }

    void closeEvent(QCloseEvent* e){
        emit close();
        QWidget::closeEvent(e);
    }

signals:
    void close();
};

class PrimaryWindow : public myOwnWidget{
    PrimaryWindow(myOwnWidget *parent):
        myOwnWidget(parent)
    {
        //your constructor here
    }

}

using:

PrimaryWindow * rootWindows = new PrimaryWindow();
PrimaryWindow * childWin = new PrimaryWindow(rootWindows);

In code PrimaryWindow create without Qt-parent, but for closing child windows you should inherit all your windows from myOwnWidget.

Hope it help.