Qt 5.6 | Qt Widgets | Fridge Magnets Example | draglabel.cpp Example File

Qt 5.6.2 Reference Documentation

# draglabel.cpp Example File

draganddrop/fridgemagnets/draglabel.cpp

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      #include "draglabel.h"

      #include <QtWidgets>

      DragLabel::DragLabel(const QString &text, QWidget *parent)
          : QLabel(parent)
      {
          QFontMetrics metric(font());
          QSize size = metric.size(Qt::TextSingleLine, text);

          QImage image(size.width() + 12, size.height() + 12, QImage::Format_ARGB32_Premultiplied);
          image.fill(qRgba(0, 0, 0, 0));

          QFont font;
          font.setStyleStrategy(QFont::ForceOutline);

          QLinearGradient gradient(0, 0, 0, image.height()-1);
          gradient.setColorAt(0.0, Qt::white);
          gradient.setColorAt(0.2, QColor(200, 200, 255));
          gradient.setColorAt(0.8, QColor(200, 200, 255));
          gradient.setColorAt(1.0, QColor(127, 127, 200));

          QPainter painter;
          painter.begin(&image);
          painter.setRenderHint(QPainter::Antialiasing);
          painter.setBrush(gradient);
          painter.drawRoundedRect(QRectF(0.5, 0.5, image.width()-1, image.height()-1),
                                  25, 25, Qt::RelativeSize);

          painter.setFont(font);
          painter.setBrush(Qt::black);
          painter.drawText(QRect(QPoint(6, 6), size), Qt::AlignCenter, text);
          painter.end();

          setPixmap(QPixmap::fromImage(image));
          m_labelText = text;
      }

      QString DragLabel::labelText() const
      {
          return m_labelText;
      }