Question

Ok so when I run this (wrote it up just to display the problem) :

#include <QtGui/QApplication>
#include "mainwindow.h"
#include <QtGUI>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QWidget *window = new QWidget;

    QPushButton *MainInter = new QPushButton("Push me!",window);

    QObject::connect(MainInter,SIGNAL(released()),MainInter,SLOT(move(100,100)));

    window->resize(900,500);
    window->show();
    return a.exec();
}

Why doesn’t the button move when clicked? 🙂

Answer 1

move is not a slot, but an accessor to change the pos property, it can’t be connected directly to a signal. But you can connect the signal to the start() slot of QPropertyAnimation which will change that property:

QPushButton *MainInter = new QPushButton("Push me!",window);

QPropertyAnimation *animation = new QPropertyAnimation(MainInter, "pos");
// To make the move instantaneous
animation->setDuration(0);
animation->setEndValue(QPoint(100,100));

QObject::connect(MainInter, SIGNAL(released()), animation, SLOT(start()));
...

or make that property value part of a state of a QStateMachine and use the signal to transition to that state:

QPushButton *MainInter = new QPushButton("Push me!",window);

QStateMachine *machine = new QStateMachine();
QState *s1 = new QState(machine);
QState *s2 = new QState(machine);
// the transition replaces the connect statement
s1->addTransition(MainInter, SIGNAL(released()), s2);
s2->assignProperty(MainInter, "pos", QPoint(100,100));
machine->setInitialState(s1);
machine->start();    
...