norwegianwoodstyle.cpp Example File

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  #include <QtWidgets>

  #include "norwegianwoodstyle.h"

  NorwegianWoodStyle::NorwegianWoodStyle() :
      QProxyStyle(QStyleFactory::create("windows"))
  {
  }

  void NorwegianWoodStyle::polish(QPalette &palette)
  {
      QColor brown(212, 140, 95);
      QColor beige(236, 182, 120);
      QColor slightlyOpaqueBlack(0, 0, 0, 63);

      QPixmap backgroundImage(":/images/woodbackground.png");
      QPixmap buttonImage(":/images/woodbutton.png");
      QPixmap midImage = buttonImage;

      QPainter painter;
      painter.begin(&midImage);
      painter.setPen(Qt::NoPen);
      painter.fillRect(midImage.rect(), slightlyOpaqueBlack);
      painter.end();

      palette = QPalette(brown);

      palette.setBrush(QPalette::BrightText, Qt::white);
      palette.setBrush(QPalette::Base, beige);
      palette.setBrush(QPalette::Highlight, Qt::darkGreen);
      setTexture(palette, QPalette::Button, buttonImage);
      setTexture(palette, QPalette::Mid, midImage);
      setTexture(palette, QPalette::Window, backgroundImage);

      QBrush brush = palette.background();
      brush.setColor(brush.color().dark());

      palette.setBrush(QPalette::Disabled, QPalette::WindowText, brush);
      palette.setBrush(QPalette::Disabled, QPalette::Text, brush);
      palette.setBrush(QPalette::Disabled, QPalette::ButtonText, brush);
      palette.setBrush(QPalette::Disabled, QPalette::Base, brush);
      palette.setBrush(QPalette::Disabled, QPalette::Button, brush);
      palette.setBrush(QPalette::Disabled, QPalette::Mid, brush);
  }

  void NorwegianWoodStyle::polish(QWidget *widget)
  {
      if (qobject_cast<QPushButton *>(widget)
              || qobject_cast<QComboBox *>(widget))
          widget->setAttribute(Qt::WA_Hover, true);
  }

  void NorwegianWoodStyle::unpolish(QWidget *widget)
  {
      if (qobject_cast<QPushButton *>(widget)
              || qobject_cast<QComboBox *>(widget))
          widget->setAttribute(Qt::WA_Hover, false);
  }

  int NorwegianWoodStyle::pixelMetric(PixelMetric metric,
                                      const QStyleOption *option,
                                      const QWidget *widget) const
  {
      switch (metric) {
      case PM_ComboBoxFrameWidth:
          return 8;
      case PM_ScrollBarExtent:
          return QProxyStyle::pixelMetric(metric, option, widget) + 4;
      default:
          return QProxyStyle::pixelMetric(metric, option, widget);
      }
  }

  int NorwegianWoodStyle::styleHint(StyleHint hint, const QStyleOption *option,
                                    const QWidget *widget,
                                    QStyleHintReturn *returnData) const
  {
      switch (hint) {
      case SH_DitherDisabledText:
          return int(false);
      case SH_EtchDisabledText:
          return int(true);
      default:
          return QProxyStyle::styleHint(hint, option, widget, returnData);
      }
  }

  void NorwegianWoodStyle::drawPrimitive(PrimitiveElement element,
                                         const QStyleOption *option,
                                         QPainter *painter,
                                         const QWidget *widget) const
  {
      switch (element) {
      case PE_PanelButtonCommand:
          {
              int delta = (option->state & State_MouseOver) ? 64 : 0;
              QColor slightlyOpaqueBlack(0, 0, 0, 63);
              QColor semiTransparentWhite(255, 255, 255, 127 + delta);
              QColor semiTransparentBlack(0, 0, 0, 127 - delta);

              int x, y, width, height;
              option->rect.getRect(&x, &y, &width, &height);

              QPainterPath roundRect = roundRectPath(option->rect);
              int radius = qMin(width, height) / 2;

              QBrush brush;
              bool darker;

              const QStyleOptionButton *buttonOption =
                      qstyleoption_cast<const QStyleOptionButton *>(option);
              if (buttonOption
                      && (buttonOption->features & QStyleOptionButton::Flat)) {
                  brush = option->palette.background();
                  darker = (option->state & (State_Sunken | State_On));
              } else {
                  if (option->state & (State_Sunken | State_On)) {
                      brush = option->palette.mid();
                      darker = !(option->state & State_Sunken);
                  } else {
                      brush = option->palette.button();
                      darker = false;
                  }
              }

              painter->save();
              painter->setRenderHint(QPainter::Antialiasing, true);
              painter->fillPath(roundRect, brush);
              if (darker)
                  painter->fillPath(roundRect, slightlyOpaqueBlack);

              int penWidth;
              if (radius < 10)
                  penWidth = 3;
              else if (radius < 20)
                  penWidth = 5;
              else
                  penWidth = 7;

              QPen topPen(semiTransparentWhite, penWidth);
              QPen bottomPen(semiTransparentBlack, penWidth);

              if (option->state & (State_Sunken | State_On))
                  qSwap(topPen, bottomPen);

              int x1 = x;
              int x2 = x + radius;
              int x3 = x + width - radius;
              int x4 = x + width;

              if (option->direction == Qt::RightToLeft) {
                  qSwap(x1, x4);
                  qSwap(x2, x3);
              }

              QPolygon topHalf;
              topHalf << QPoint(x1, y)
                      << QPoint(x4, y)
                      << QPoint(x3, y + radius)
                      << QPoint(x2, y + height - radius)
                      << QPoint(x1, y + height);

              painter->setClipPath(roundRect);
              painter->setClipRegion(topHalf, Qt::IntersectClip);
              painter->setPen(topPen);
              painter->drawPath(roundRect);

              QPolygon bottomHalf = topHalf;
              bottomHalf[0] = QPoint(x4, y + height);

              painter->setClipPath(roundRect);
              painter->setClipRegion(bottomHalf, Qt::IntersectClip);
              painter->setPen(bottomPen);
              painter->drawPath(roundRect);

              painter->setPen(option->palette.foreground().color());
              painter->setClipping(false);
              painter->drawPath(roundRect);

              painter->restore();
          }
          break;
      default:
          QProxyStyle::drawPrimitive(element, option, painter, widget);
      }
  }

  void NorwegianWoodStyle::drawControl(ControlElement element,
                                       const QStyleOption *option,
                                       QPainter *painter,
                                       const QWidget *widget) const
  {
      switch (element) {
      case CE_PushButtonLabel:
          {
              QStyleOptionButton myButtonOption;
              const QStyleOptionButton *buttonOption =
                      qstyleoption_cast<const QStyleOptionButton *>(option);
              if (buttonOption) {
                  myButtonOption = *buttonOption;
                  if (myButtonOption.palette.currentColorGroup()
                          != QPalette::Disabled) {
                      if (myButtonOption.state & (State_Sunken | State_On)) {
                          myButtonOption.palette.setBrush(QPalette::ButtonText,
                                  myButtonOption.palette.brightText());
                      }
                  }
              }
              QProxyStyle::drawControl(element, &myButtonOption, painter, widget);
          }
          break;
      default:
          QProxyStyle::drawControl(element, option, painter, widget);
      }
  }

  void NorwegianWoodStyle::setTexture(QPalette &palette, QPalette::ColorRole role,
                                      const QPixmap &pixmap)
  {
      for (int i = 0; i < QPalette::NColorGroups; ++i) {
          QColor color = palette.brush(QPalette::ColorGroup(i), role).color();
          palette.setBrush(QPalette::ColorGroup(i), role, QBrush(color, pixmap));
      }
  }

  QPainterPath NorwegianWoodStyle::roundRectPath(const QRect &rect)
  {
      int radius = qMin(rect.width(), rect.height()) / 2;
      int diam = 2 * radius;

      int x1, y1, x2, y2;
      rect.getCoords(&x1, &y1, &x2, &y2);

      QPainterPath path;
      path.moveTo(x2, y1 + radius);
      path.arcTo(QRect(x2 - diam, y1, diam, diam), 0.0, +90.0);
      path.lineTo(x1 + radius, y1);
      path.arcTo(QRect(x1, y1, diam, diam), 90.0, +90.0);
      path.lineTo(x1, y2 - radius);
      path.arcTo(QRect(x1, y2 - diam, diam, diam), 180.0, +90.0);
      path.lineTo(x1 + radius, y2);
      path.arcTo(QRect(x2 - diam, y2 - diam, diam, diam), 270.0, +90.0);
      path.closeSubpath();
      return path;
  }