[Solved] UI form connection error

[gerberka]

I created widget in qt designer, and I want to connect widget's buttons with slots of my objects but when I add row with connection code my programm crash :( Thanks for answers!

mainwindow.cpp
@
void MainWindow::AddImages(){
...
Ui::ImageProperties ui;
foreach (const QString &str, list) {
QWidget widget = new QWidget;
ui.setupUi(widget);
ui.label->setText(str);
ImageItem item = (ImageItem*)(scene->addPixmap(QPixmap(str)));
connect(ui.checkBox,SIGNAL(stateChanged(int)),item,SLOT(changeVisibility(int)));
images.append(item);
propImagesLayout->addWidget(widget);
}
@

mainwindow.h
@
QList<ImageItem*> images;
QVBoxLayout* propImagesLayout;
@
imageitem class
@
class ImageItem : public QObject, public QGraphicsPixmapItem
{
Q_OBJECT
public:
ImageItem(QPixmap pixmap) : QGraphicsPixmapItem(pixmap){}

public slots:
void changeVisibility(int state){
if(state == 0)hide();
else show();
}
void changeOpacity(int level){
setOpacity(level/10);
}
};
@

[dheerendra]

ImageItem* item = (ImageItem*)(scene->addPixmap(QPixmap(str)));

Just check above statement. Item is definitely null here. AddPixmap may not be working.

[gerberka]

Thank you!
I edit class ImageItem and programm work
@
class ImageItem : public QObject
{
Q_OBJECT
private:
QGraphicsPixmapItem *m_pixmap;
public:
ImageItem(QGraphicsPixmapItem *pixmap){
m_pixmap = pixmap;
}

public slots:
void changeVisibility(int state){
if(state == 0)m_pixmap->hide();
else m_pixmap->show();
}
void changeOpacity(int level){
m_pixmap->setOpacity(level/10);
}
};
@