volumebutton.cpp Example File

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  #include "volumebutton.h"

  #include <QtWidgets>
  #include <QtWinExtras>

  VolumeButton::VolumeButton(QWidget *parent) :
      QToolButton(parent)
  {
      setIcon(style()->standardIcon(QStyle::SP_MediaVolume));
      setPopupMode(QToolButton::InstantPopup);

      QWidget *popup = new QWidget(this);

      slider = new QSlider(Qt::Horizontal, popup);
      slider->setRange(0, 100);
      connect(slider, &QAbstractSlider::valueChanged, this, &VolumeButton::volumeChanged);

      label = new QLabel(popup);
      label->setAlignment(Qt::AlignCenter);
      label->setNum(100);
      label->setMinimumWidth(label->sizeHint().width());

      connect(slider, &QAbstractSlider::valueChanged, label, QOverload<int>::of(&QLabel::setNum));

      QBoxLayout *popupLayout = new QHBoxLayout(popup);
      popupLayout->setMargin(2);
      popupLayout->addWidget(slider);
      popupLayout->addWidget(label);

      QWidgetAction *action = new QWidgetAction(this);
      action->setDefaultWidget(popup);

      menu = new QMenu(this);
      menu->addAction(action);
      setMenu(menu);

      stylize();
  }

  void VolumeButton::increaseVolume()
  {
      slider->triggerAction(QSlider::SliderPageStepAdd);
  }

  void VolumeButton::descreaseVolume()
  {
      slider->triggerAction(QSlider::SliderPageStepSub);
  }

  int VolumeButton::volume() const
  {
      return slider->value();
  }

  void VolumeButton::setVolume(int volume)
  {
      slider->setValue(volume);
  }

  void VolumeButton::stylize()
  {
      if (QOperatingSystemVersion::current() < QOperatingSystemVersion::Windows8) {
          // Set styling options relevant only to Windows 7.
          if (QtWin::isCompositionEnabled()) {
              QtWin::enableBlurBehindWindow(menu);
              QString css("QMenu { border: 1px solid %1; border-radius: 2px; background: transparent; }");
              menu->setStyleSheet(css.arg(QtWin::realColorizationColor().name()));
          } else {
              QtWin::disableBlurBehindWindow(menu);
              QString css("QMenu { border: 1px solid black; background: %1; }");
              menu->setStyleSheet(css.arg(QtWin::realColorizationColor().name()));
          }
      }
  }