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Two Way Button Problem



  • Hi all,
    Sorry for noob question but i'm a newbie with qt and C++ isn't my primary language.
    I've created in Qt Design a button named ResistenzeOn, with a slot clicked(); .
    In my mainwindow.h i've declared this :

    #ifndef MAINWINDOW_H
    #define MAINWINDOW_H

    #include <QtGui>
    #include <QSize>
    #include <QDebug>
    #include <QMainWindow>
    #include <QMessageBox>
    #include <QWidget>

    namespace Ui {
    class MainWindow;
    }

    class MainWindow : public QMainWindow
    {
    Q_OBJECT

    public:
    explicit MainWindow(QWidget *parent = 0);

    QState *off;
    QState *on;
    QStateMachine machine;
    
    
    
    ~MainWindow();
    

    private slots:

    void on_ResistenzeOn_clicked();
    

    private:

    Ui::MainWindow *ui;
    

    };

    #endif // MAINWINDOW_H

    In mainwindow.cpp:

    MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
    {
    ui->setupUi(this);

    off = new QState();
    off->assignProperty(ui->ResistenzeOn,"text","On");
    off->setObjectName("off");
    
    on = new QState();
    on->assignProperty(ui->ResistenzeOn,"text","Off");
    
    off->addTransition(ui->ResistenzeOn, SIGNAL(on_ResistenzeOn_clicked()), on);
    on ->addTransition(ui->ResistenzeOn, SIGNAL(on_ResistenzeOn_clicked()), off);
    
    machine.addState(off);
    machine.addState(on);
    
    machine.setInitialState(off);
    machine.start();
    

    }

    MainWindow::~MainWindow()
    {
    delete ui;
    }

    void MainWindow::on_ResistenzeOn_clicked()
    {

    gpioWrite(OUT_RES, 1);
    ui->labelResistence->setPixmap(MainWindow::fireScaled);
    

    }

    But when i run the program the output is :
    QState::addTransition: no such signal QPushButton::on_ResistenzeOn_clicked()

    I cannot understand where is the problem.
    Ho can i call a specific function based on the button state?
    Thanks,
    Giovanni


  • Lifetime Qt Champion

    Hi,

    on_ResistenzeOn_clicked is not a signal but a slot that will be automatically connect to your button when ui->setupUi(this) is called. What you want to connect to your states is the button's clicked() signal.



  • SGaist, thanks a lot,
    but how can i specify which function is called when the transition occur?
    Thanks,
    Giovanni


  • Lifetime Qt Champion

    What function would you like to call ?



  • @SGaist : Thanks for your time.
    I have a function that set to ON or OFF a PIN using PIGPIO:

    gpioWrite(pinNumber, level);

    When i click and the state go to off i need to call gpioWrite(21,0); when go to on i will call gpioWrite(21,1);

    Thanks.
    Giovanni


  • Lifetime Qt Champion

    Do you have a dedicated object that handles the GPIOs ?

    In any case you can use two slots, one for each state that you can connect to the corresponding state's entered signal.


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