Connection from a signal to a slot returns false

Question

I have the following class declaration:

class nets_list : public QDockWidget
{
    Q_OBJECT

private:
    QListView * files;

public slots:
    void SelectNet(QModelIndex i);

signals:
    void NetSelected(QString t);

public:
    nets_list(QWidget * parent = nullptr);
};

At some point in my nets_list constructor, I want to connect a clicked(QModelIndex) signal of the files member to the NetRunner(QString) slot in the parent of my class:

bool x1 = connect(files, SIGNAL(clicked(QModelIndex)), this, SLOT(SelectNet(QModelIndex)));
bool x2 = connect(this, SIGNAL(NetSelected(QString)), parent, SLOT(NetRunner(QString)));

The code for SelectNet() is just:

void nets_list::SelectNet(QModelIndex i)
{
    emit NetSelected(fs->fileName(i));
}

because I just want to extract a QString from the QModelIndex parameter so that I can call the slot in the parent class.

The problem is that the second connect call returns false (bool x2 appears to be false). Why?

Also: is there a better solution for connecting signals and slots with different parameter types? I thought that using an "intermediate" function such as my SelectNet(QModelIndex) slot was a good solution.

EDIT:

the parent class is

class MW : public QMainWindow
{
    Q_OBJECT

private:
    QMenu * net_menu;
    QMenuBar * menu_bar;

    QStackedWidget * ctrl;
    netBuilderWidget * builder;
    netTrainerWidget * trainer;
    netRunnerWidget * runner;

    nets_list * nets_dock;

public slots:
    void netBuilder();
    void netTrainer();
    void netRunner(QString t);

    void addNet();

public:
    MW();
    QSize minimumSizeHint() const Q_DECL_OVERRIDE;
    QSize sizeHint() const Q_DECL_OVERRIDE;
};

Answer 1

replace

SLOT(NetRunner(QString))

with

SLOT(netRunner(QString))

and the connect should work.