QTimer not calling slot

[been_1990]

I have a QObject subclass that sets a timer to call a slot. But that never happens.

shot.h:

#ifndef SHOT_H
#define SHOT_H
 
#include <QObject>
#include <QTimer>
 
 
class Shot : public QObject
{
    Q_OBJECT
public:
    explicit Shot(QObject *parent = 0);
private:
    QTimer *timer;
public slots:
    void updatePos();
 
};
 
#endif // SHOT_H

#ifndef SHOT_H
#define SHOT_H

#include <QObject>
#include <QTimer>


class Shot : public QObject
{
    Q_OBJECT
public:
    explicit Shot(QObject *parent = 0);
private:
    QTimer *timer;
public slots:
    void updatePos();

};

#endif // SHOT_H

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shot.cpp:

#include "shot.h"
#include <QDebug>
 
Shot::Shot(QObject *parent) :
    QObject(parent)
{
    timer = new QTimer();
    connect(timer, SIGNAL(timeout()), this, SLOT(updatePos()));
    timer->setInterval(0);
    timer->start();
}
 
void Shot::updatePos()
{
    //timer never reaches here...
}

#include "shot.h"
#include <QDebug>

Shot::Shot(QObject *parent) :
    QObject(parent)
{
    timer = new QTimer();
    connect(timer, SIGNAL(timeout()), this, SLOT(updatePos()));
    timer->setInterval(0);
    timer->start();
}

void Shot::updatePos()
{
    //timer never reaches here...
}

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[tbscope]

Does the slot really exist? Is the file processed by moc?

[wysota]

Is the event loop running?

[been_1990]

Does the slot really exist? Is the file processed by moc?

Yes, it does:

public slots:
void updatePos()

public slots:
void updatePos()

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;

Is the event loop running?

Hmmm.. I think so. This is a class I call to create an item when needed.

if(btn1){
            ui->lineEdit->setText("cliked");
            Shot tiro;
}

if(btn1){
            ui->lineEdit->setText("cliked");
            Shot tiro;
}

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[wysota]

Think what is the scope of your "tiro" object and what happens to it when line #4 of the code is reached.

[been_1990]

@#!!%&* I should really take a shot on the head.

Scope, I always forget.... Thanks for the patience.

BTW, why is QGraphicsView so slow when updating an item's position?

[wysota]

BTW, why is QGraphicsView so slow when updating an item's position?

Because you are not using it correctly.

[been_1990]

I'm using setPos(x,y) to update it's position. Isn't that correct? I checked out the "40000 Chips" example, and copied some settings from it's QGraphicsView:

graphicsView->setOptimizationFlags(QGraphicsView::DontSavePainterState);
     graphicsView->setViewportUpdateMode(QGraphicsView::SmartViewportUpdate);

graphicsView->setOptimizationFlags(QGraphicsView::DontSavePainterState);
     graphicsView->setViewportUpdateMode(QGraphicsView::SmartViewportUpdate);

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But it still goes slow. Where can I see an example of correct implementation of QGraphicsView with changing elements positions(not drag-'n-drop)

[wysota]

There is no correct implementation of Graphics View bla bla bla. What is correct depends on a case-by-case basis.