catch signal stepDown from doubleSpinBox

[pospiech]

I want to catch teh up and down signals from QAbstractSpinBox within a QDoubleSpinBox instance:

connect(doubleSpinBox, SIGNAL(stepDown()), this, SLOT(OnUnitStepDown()));
	connect(doubleSpinBox, SIGNAL(stepUp () ), this, SLOT(OnUnitStepUp()));

connect(doubleSpinBox, SIGNAL(stepDown()), this, SLOT(OnUnitStepDown()));
	connect(doubleSpinBox, SIGNAL(stepUp () ), this, SLOT(OnUnitStepUp()));

To copy to clipboard, switch view to plain text mode 

however that only results in

no such Signal QDoubleSpinBox::stepDown()
...

how do I do it then?

[caduel]

stepDown() is a slot. You can not connect to a slot.

[pospiech]

stepDown() is a slot. You can not connect to a slot.

ok, I have overlooked that. However I need to get a signal upon upper and lower Buttons. Is there any way to implement something that does that?

[caduel]

You can subclass the spinbox and override the stepBy() method.
Apart from that, maybe the valueChanged signal?

[pospiech]

You can subclass the spinbox and override the stepBy() method.
Apart from that, maybe the valueChanged signal?

What I need is the buttons. They shall not change the value, I just want to know that they are pressed.

I could also live with a doublespinbox without any buttons and standalone buttons without any edit area.

I tried to subclass from qdoublespinbox, but that does not work.

[caduel]

in what way did subclassing not work?

[pospiech]

in what way did subclassing not work?

class QScienceLineEdit : public QDoubleSpinBox
{
	Q_OBJECT
public:
	QScienceLineEdit(QWidget* parent = 0, Qt::WFlags flags = 0);
	virtual ~QScienceLineEdit();
...

class QScienceLineEdit : public QDoubleSpinBox
{
	Q_OBJECT
public:
	QScienceLineEdit(QWidget* parent = 0, Qt::WFlags flags = 0);
	virtual ~QScienceLineEdit();
...

To copy to clipboard, switch view to plain text mode 

fails at line

Q_DECLARE_PRIVATE(QDoubleSpinBox)

Q_DECLARE_PRIVATE(QDoubleSpinBox)

To copy to clipboard, switch view to plain text mode 

in qspinbox.h

[caduel]

That should not be the case. Can you show us you .pro file, and the complete header file?

[pospiech]

Now I tried to subclass from doubleSpinBox again. It works now (new project, dont know why it failed in the old one).

However the slot:
void QScienceSpinBox::stepDown()

is never called if I press up or down arrows.

The code is looking like this:

class QScienceSpinBox : public QDoubleSpinBox
{
Q_OBJECT
public:
    QScienceSpinBox(QWidget * parent = 0);
 
    QString textFromValue ( double value ) const;
    double valueFromText ( const QString & text ) const;
...	
private slots:
	void stepDown();
	void stepUp();
 
};

class QScienceSpinBox : public QDoubleSpinBox
{
Q_OBJECT
public:
    QScienceSpinBox(QWidget * parent = 0);

    QString textFromValue ( double value ) const;
    double valueFromText ( const QString & text ) const;
...	
private slots:
	void stepDown();
	void stepUp();

};

To copy to clipboard, switch view to plain text mode 

[rexi]

Is it only the stepDown slot? The stepUp/Down slots are public in QDoubleSpinBox, and you are redeclaring them as private. Maybe that's causing your problem.

[pospiech]

Is it only the stepDown slot? The stepUp/Down slots are public in QDoubleSpinBox, and you are redeclaring them as private. Maybe that's causing your problem.

makeing the slots public changes nothing. The functions are still not called at button up or down.

EDIT:
If I use the correct virtual function it works:

// overwritten virtual function of QAbstractSpinBox
void QScienceSpinBox::stepBy(int steps)
{
	if (steps < 0)
		stepDown();
	else
		stepUp();
}
 
void QScienceSpinBox::stepDown()
{
	QSBDEBUG() << "stepDown()";
	setValue(value()/10.0);
}
 
void QScienceSpinBox::stepUp()
{
	QSBDEBUG() << "stepUp()";
	setValue(value()*10.0);
}

// overwritten virtual function of QAbstractSpinBox
void QScienceSpinBox::stepBy(int steps)
{
	if (steps < 0)
		stepDown();
	else
		stepUp();
}

void QScienceSpinBox::stepDown()
{
	QSBDEBUG() << "stepDown()";
	setValue(value()/10.0);
}

void QScienceSpinBox::stepUp()
{
	QSBDEBUG() << "stepUp()";
	setValue(value()*10.0);
}

To copy to clipboard, switch view to plain text mode