drawing complex controls

happ

How do I draw complex controls using qstyle?
I reimplement drawComplex like other types but nothing happens.

Pl45m4

How do I draw complex controls using qstyle?
I reimplement drawComplex like other types but nothing happens.

That's not much information.

Show what you did exactly.

happ

@Pl45m4 whenever i set my custom style to my app (QApplication) all the complex controls disappear).
this is the drawComplex code that i've written:

void ChangeSlider(const QStyleOptionComplex *opt, QPainter* painter, const QWidget* w)
{
    if(opt->state == QStyle::State_Active)
    {
        if(opt->activeSubControls == QStyle::SC_SliderHandle)
        {
            painter->setBrush(QColor(0xe6, 0x00, 0x00));
            painter->setPen(QColor(0xe6, 0x00, 0x00));
        }
        else if(opt->activeSubControls == QStyle::SC_SliderHandle)
        {
            painter->setBrush(QColor(0x4D, 0xA6, 0xFF));
            painter->setPen(QColor(0x4D, 0xA6, 0xFF));
        }
    }
    painter->drawRect(opt->rect);
}

void GlobalStyles::drawComplexControl(ComplexControl cc, const QStyleOptionComplex *opt, QPainter *p,
                          const QWidget *w) const
{
      switch(cc)
      {
      case QStyle::CC_Slider:
          ChangeSlider(opt, p, w);
          return;
      default:
          QCommonStyle::drawComplexControl(cc,opt,p,w);
      }

 }

what am i doing wrong here?

Pl45m4

@happ

So you custom slider subclass has GlobalStyles style set?!
Do you only call style()->drawComplexControl(........) within the sliders paintEvent?
Otherwise it would get overridden.

If you look at QSliders default implementation:
Qt6

void QSlider::paintEvent(QPaintEvent *)
{
    Q_D(QSlider);
    QStylePainter p(this);
    QStyleOptionSlider opt;
    initStyleOption(&opt);
    opt.subControls = QStyle::SC_SliderGroove | QStyle::SC_SliderHandle;
    if (d->tickPosition != NoTicks)
        opt.subControls |= QStyle::SC_SliderTickmarks;
    p.drawComplexControl(QStyle::CC_Slider, opt);
}

Qt5 (slightly different)

void QSlider::paintEvent(QPaintEvent *)
{
    Q_D(QSlider);
    QPainter p(this);
    QStyleOptionSlider opt;
    initStyleOption(&opt);
    opt.subControls = QStyle::SC_SliderGroove | QStyle::SC_SliderHandle;
    if (d->tickPosition != NoTicks)
        opt.subControls |= QStyle::SC_SliderTickmarks;
    if (d->pressedControl) {
        opt.activeSubControls = d->pressedControl;
        opt.state |= QStyle::State_Sunken;
    } else {
        opt.activeSubControls = d->hoverControl;
    }
    style()->drawComplexControl(QStyle::CC_Slider, &opt, &p, this);
}

@happ said in drawing complex controls:

whenever i set my custom style to my app (QApplication) all the complex controls disappear).

Edit:

Haven't seen that... ;-)
I assume because your style only contains information on how to draw a QSlider.
You might have lost everything else.

(not sure about that, maybe somebody else can verify that)

medyakovvit

@happ Does your style inherit QCommonStyle? If you want other widgets to look like there is no custom style then you can use proxy style.
And here is how you create your style:

auto proxy = new MyProxyStyle(QApplication::style()->name());
proxy->setParent(widget);   // take ownership to avoid memleak
widget->setStyle(proxy);

Notice that the name of the default application style is used to create a proxy style.

There are a layer of OS-dependent styles where an OS-specific drawing happens but they are private. The QCommonStyle probably contains some general drawing only.

happ

@medyakovvit

I was inheriting QCommonStyle when i used QProxyStyle they started showing up but my changes aren't still being implemented.

medyakovvit

@happ I mean that you can inherit your style from QProxyStyle instead of QCommonStyle

class CustomStyle : public QProxyStyle
{
public:
    CustomStyle(cosnt QString styleName): QProxyStyle(styleName) {...}

    virtual void drawComplexControl(ComplexControl cc, const QStyleOptionComplex *opt, QPainter *p, const QWidget *w) const override
    {
        switch(cc)
        {
            case QStyle::CC_Slider:
              // draw your slider
            return;
    
          default: QProxyStyle::drawComplexControl(cc,opt,p,w);
    }
}

// In the code where you create the slider
auto slider = new QSlider();
auto proxy = new CustomStyle(QApplication::style()->name());
proxy->setParent(slider);   // take ownership to avoid memleak
slider->setStyle(proxy);