QWidgetAction doesn't work inside QMenu as a context menu for tray

Question

I'm trying to insert a QWidgetAction inside a QMenu, which will be used as a context menu for tray. When I do this, I only get an empty line inside my menu.

I'm using:

• Qt 5.5.1.
• Plasma 5 desktop environment (Linux).

Here is my code:

action = new QWidgetAction(0);
testw = new QWidget();
testl = new QLabel(QString("Test"), testw);

action->setDefaultWidget(testw);

menu.addAction(action);
trayIcon.setContextMenu(&menu);

If I use menu.addAction(QString("Test")); it is displayed properly.

All the variables are members of my class.

Answer 1

As long as you already have the menu shown then the problem is with extra widget you wrap the QLabel with. This is the way QWdigetAction usually works:

QWidgetAction* pWidgetAction = new QWidgetAction(0); // no parent-owner?
QLabel* pLabelWidget = new QLabel("Test");           // label widget
pWidgetAction->setDefaultWidget(pLabelWidget);       // label is a widget
menu.addAction(pWidgetAction);                       // add widget action
trayIcon.setContextMenu(&menu);                      // this I assume works

Also unsure of the life-cycle of these objects (the ownership) and why menu and trayIcon are not pointers but you should be more clear about that. By default I always create UI objects with new and pass the parent widget/object address to constructor though we can have those on stack as well (not flexible approach).