PROBLEM TO SIGNALS AND SLOTS

Giakara

I Create A custom widget Class in main window and i try to connect a slider from mainwindow to a function in Qustom class. App starts correctly but when i move the slider it gets The program has unexpectedly finished.

jsulm

@Giakara said in PROBLEM TO SIGNALS AND SLOTS:

The program has unexpectedly finished

So, did you use the debugger to see where and why it crashes?
Is "window" a valid pointer?

Also, please post code as text, not pictures.

Giakara

The debugger shows an error about qtcreatordbext.dll not found

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; class WindowWidget; }
QT_END_NAMESPACE

class WindowWidget : public QWidget {
Q_OBJECT
public:
WindowWidget(QWidget *parent = nullptr) {

//code//

       fast::SurfaceExtraction::pointer mSurfaceExtraction = fast::SurfaceExtraction::New();
       mSurfaceExtraction->setInputConnection(mSmoothing->getOutputPort());
       mSurfaceExtraction->setThreshold(0);

    };
    ~WindowWidget() {
        fast::Reporter::info() << "Trying to stop computation thread" << fast::Reporter::end();
        if(mThread != NULL) {
            mThread->stop();
            delete mThread;
            mThread = NULL;
        }
        fast::Reporter::info() << "Computation thread stopped" << fast::Reporter::end();
    };
public slots:
    }
    void updateThreshold(int value){

        mSurfaceExtraction->setThreshold(value);

    };

private:
    fast::SurfaceExtraction::pointer mSurfaceExtraction;
    fast::ComputationThread* mThread;
    fast::View* mView;
    fast::GaussianSmoothingFilter::pointer mSmoothing;

};
class MainWindow : public QMainWindow
{
Q_OBJECT

public:
MainWindow(QWidget *parent = nullptr);
~MainWindow();

private slots:

void on_slider_valueChanged(int value);

private:
Ui::MainWindow *ui;
WindowWidget *window;
};

cpp

MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent),
ui(new Ui::MainWindow),window(new WindowWidget)
{

ui->setupUi(this);
ui->verticalLayout->addWidget(window);
//connect(ui->slider, &QSlider::valueChanged, std::bind(&WindowWidget::updateThreshold, this, std::placeholders::_1));

}

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

void MainWindow::on_slider_valueChanged(int value)
{

window->updateThreshold(value);

}

this is my code if i create o slider inside my Window it works (I m new to QT)

jsulm

@Giakara said in PROBLEM TO SIGNALS AND SLOTS:

void updateThreshold(int value){
    mSurfaceExtraction->setThreshold(value);

};

Please check all your pointers and fix your debugger - people here are not debuggers to analize crashes in your code without having it...

Christian Ehrlicher

@Giakara said in PROBLEM TO SIGNALS AND SLOTS:

fast::SurfaceExtraction::pointer mSurfaceExtraction = fast::SurfaceExtraction::New();

Basic++ - it does not initialize the variable you want to.