how to draw check box using qstyle in a qgraphicsitem

[wagmare]

hi friends,

how to draw checkbox using qstyle in a qgraphicsitem .?
i tried not to use qgraphicsproxy widget so i tried to use qstyle but i was facing a problem in setting the text color of the checkbox.

please correct me if im wrong in this implementation ..

class CheckBoxItem : public QGraphicsObject,public QGraphicsLayoutItem
{
public:
   CheckBoxItem(const QString & text,QGraphicsItem *parent =0);
    QString m_text;
     QRectF boundingRect() const;
protected:
    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);
 
    void mousePressEvent(QGraphicsSceneMouseEvent *event);
 
 
    QSizeF sizeHint(Qt::SizeHint which, const QSizeF &constraint) const;
    void setGeometry(const QRectF &rect);
 
 
private:
    bool m_mousePressed;
 
 
};

class CheckBoxItem : public QGraphicsObject,public QGraphicsLayoutItem
{
public:
   CheckBoxItem(const QString & text,QGraphicsItem *parent =0);
    QString m_text;
     QRectF boundingRect() const;
protected:
    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);

    void mousePressEvent(QGraphicsSceneMouseEvent *event);


    QSizeF sizeHint(Qt::SizeHint which, const QSizeF &constraint) const;
    void setGeometry(const QRectF &rect);


private:
    bool m_mousePressed;


};

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in .cpp

CheckBoxItem::CheckBoxItem(const QString &text, QGraphicsItem *parent)
    : QGraphicsObject(parent),m_mousePressed(false)
{
    m_text = text;
}
void
CheckBoxItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
    QFont font("Serif",8);
    painter->setFont(font);
 
    const QStyle *style = QApplication::style();
    QStyleOptionButton opt;
 
    opt.state |= m_mousePressed ? QStyle::State_On : QStyle::State_Off;
    opt.state |= QStyle::State_Enabled;
    // opt.palette = QPalette(Qt::red);
    opt.text = m_text;
    opt.rect = option->rect;
    opt.palette = QPalette(Qt::white);
 
    style->drawControl(QStyle::CE_CheckBox,&opt,painter);
 
}
 
QSizeF
CheckBoxItem::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
{
    return boundingRect().size();
}
 
void
CheckBoxItem::setGeometry(const QRectF &rect)
{
    setPos(rect.topLeft());
}

CheckBoxItem::CheckBoxItem(const QString &text, QGraphicsItem *parent)
    : QGraphicsObject(parent),m_mousePressed(false)
{
    m_text = text;
}
void
CheckBoxItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
    QFont font("Serif",8);
    painter->setFont(font);

    const QStyle *style = QApplication::style();
    QStyleOptionButton opt;

    opt.state |= m_mousePressed ? QStyle::State_On : QStyle::State_Off;
    opt.state |= QStyle::State_Enabled;
    // opt.palette = QPalette(Qt::red);
    opt.text = m_text;
    opt.rect = option->rect;
    opt.palette = QPalette(Qt::white);

    style->drawControl(QStyle::CE_CheckBox,&opt,painter);

}

QSizeF
CheckBoxItem::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
{
    return boundingRect().size();
}

void
CheckBoxItem::setGeometry(const QRectF &rect)
{
    setPos(rect.topLeft());
}

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i dont know how to change the color and font size of the text in check box .. but check box is coming fine ..
please help ..

[aamer4yu]

Why do you want to reinvent the wheel ? You can look for QML desktop elements since Qt 5.1

And if you are not using QML, you can anyhow add a widget to QGraphicsScene

[wagmare]

you can anyhow add a widget to QGraphicsScene

i want to add thousands of checkboxes in my view so i preffered not to go for QGraphicsWidget as to reduce load .. so i tried to make a checkbox graphicsitem with cachemode .

[spirit]

QStyleOptionButton inherits QStyleOption. QStyleOption has fontMetrics. So, I guess, you can "feed" your own font metrics in CheckBoxItem:: paint. As for text color, QStyleOption has palette, so you just need to set proper color for QPalette::WindowText or other *Text.

Other thing, you don't see you draw a check box's text using QStyle::drawControl with CE_CheckBoxLabel passed.