Problem is that I keep getting the 'No Such Slot' runtime error in Qt Creator every time I launch a 'settings' window from my main window. I've found Qt to be quite counter-intuitive so far and this slots 'n signals concept seems a bit of a stretch from simply passing vars or function calls. Basically, I have menu with a settings option, that when clicked, opens a settings window which needs to grab a double from the user and update a var in the main window.
SettingsWindow.h
class SettingsWindow : public QWidget
{
Q_OBJECT
public:
SettingsWindow(QWidget *parent = 0);
signals:
void ValChanged(double newVal);
public slots:
void Accept();
private:
QLineEdit *le1;
};
The settings window has an accept button which calls Accept() which emits the ValChanged signal with newVal set as the user input in le1 as a double.
SettingsWindow.cpp
void SettingsWindow::Accept(){
emit ValChanged(le1->text().toDouble());
this->close();
}
This settings window is called by the application's main window: MainWindow
MainWindow.cpp
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = 0);
public slots:
void SetVal(double x);
private slots:
void NewWindow();
private:
double theVal;
};
This main window has a menu which one would select settings from. This creates a new window with a field for one to enter a number.
MainWindow.cpp
void MainWindow::NewWindow()
{
SettingsWindow *MySettings=new SettingsWindow(this);
QObject::connect(MySettings, SIGNAL(ValChanged(double)), this, SLOT(SetVal(double)));
MySettings->show();
MySettings->raise();
}
void MainWindow::SetVal(double x){
theVal = x;
}
My hope is that when the settings window is opened, the user can enter a val into the field which then emits the ValChanged Signal which sets theVal to the value specified by the user. Most of the time I saw an issue with people not including Q_OBJECT macro, but I've included it both times. Any suggestions on why this doesn't work?
qt_metacall(QMetaObject::Call _c, int _id, void **_a)? – Thomas VincentNo such slot: MainWindow::SetVal(double)(without thex). If the error message is correct, and your code is reallySLOT(SetVal(double x)), then you can fix the problem by removing thex. – TonyK