[Solved] Signal/Slot connection that spans 3 classes

Endless

I have the RootWindow class which is a QMainWindow. I then instantiate the MonitorWindow class, a QWidget, from RootWindow. Next, in the constructor of MonitorWindow, I instantiate another class called StatusBar, which shows a status bar on the MonitorWindow QWidget. Here are the code snippets that do the above:

In the rootwindow.cpp file:
@
RootWindow::RootWindow(QWidget *parent) :
QMainWindow(parent)
{
showFullScreen();
myStackedWidget = new QStackedWidget(this);
monitorScreen = new MonitorWindow();
myStackedWidget->addWidget(monitorScreen);
connect(monitorScreen, SIGNAL(activateScreen(int)), this, SLOT(setCurrentScreen(int)));
}
@
In the monitorwindow.cpp file:
@
MonitorWindow::MonitorWindow(QWidget *parent) :
QWidget(parent),
ui(new Ui::MonitorWindow)
{
ui->setupUi(this);

// Instantiate status bar and connect it
statusBar = new StatusBar(this);
connect(this, SIGNAL(statusChanged(int)), statusBar, SLOT(updateStatusSlot(int)));
connect(this, SIGNAL(faultStatusChanged(int)), statusBar, SLOT(updateFaultSlot(int)));
connect(statusBar, SIGNAL(showSiteMap()), this, SLOT(sendSiteMapRequest()));

}
@
What I'd like to do is add a fourth connection to the three listed immediately above that connects a signal from StatusBar to a slot in RootWindow. Since RootWindow is two levels above StatusBar, how would I go about doing that?

d2uriel

Maybe something like:
@connect(this->statusBar, SIGNAL(something()), /maybe a cast here/this->parent(), SLOT(somethingElse()));@
?

No idea if it will work :P.

mlong

Create a duplicate signal in your MonitorWindow class and chain them together. For instance, if you wanted to expose the statusbar's showSiteMap signal, you could do:
@
class MonitorWindow ...
{
...
signal:
void showSiteMap();
...
}
@

And in the c'tor do:
@
MonitorWindow::MonitorWindow(...)
{
...
statusBar = new StatusBar(...);

connect(statusBar, SIGNAL(showSiteMap()), this, SIGNAL(showSiteMap()));
...
}
@

Then in your root window you can connect to MonitorWindow's "showSiteMap()" signal.

@
RootWindow::RootWindow(QWidget *parent) :
QMainWindow(parent)
{
...
monitorScreen = new MonitorWindow();

connect(monitorScreen, SIGNAL(showSiteMap()), this, SLOT(doWhatever()));

...
}
@

andre

Note that the SIGNAL/SIGNAL connection in the example of mlong above is not a mistake. You can connect signals together.