borderlayout.cpp Example File

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  #include "borderlayout.h"

  BorderLayout::BorderLayout(QWidget *parent, int margin, int spacing)
      : QLayout(parent)
  {
      setMargin(margin);
      setSpacing(spacing);
  }

  BorderLayout::BorderLayout(int spacing)
  {
      setSpacing(spacing);
  }

  BorderLayout::~BorderLayout()
  {
      QLayoutItem *l;
      while ((l = takeAt(0)))
          delete l;
  }

  void BorderLayout::addItem(QLayoutItem *item)
  {
      add(item, West);
  }

  void BorderLayout::addWidget(QWidget *widget, Position position)
  {
      add(new QWidgetItem(widget), position);
  }

  Qt::Orientations BorderLayout::expandingDirections() const
  {
      return Qt::Horizontal | Qt::Vertical;
  }

  bool BorderLayout::hasHeightForWidth() const
  {
      return false;
  }

  int BorderLayout::count() const
  {
      return list.size();
  }

  QLayoutItem *BorderLayout::itemAt(int index) const
  {
      ItemWrapper *wrapper = list.value(index);
      if (wrapper)
          return wrapper->item;
      else
          return 0;
  }

  QSize BorderLayout::minimumSize() const
  {
      return calculateSize(MinimumSize);
  }

  void BorderLayout::setGeometry(const QRect &rect)
  {
      ItemWrapper *center = 0;
      int eastWidth = 0;
      int westWidth = 0;
      int northHeight = 0;
      int southHeight = 0;
      int centerHeight = 0;
      int i;

      QLayout::setGeometry(rect);

      for (i = 0; i < list.size(); ++i) {
          ItemWrapper *wrapper = list.at(i);
          QLayoutItem *item = wrapper->item;
          Position position = wrapper->position;

          if (position == North) {
              item->setGeometry(QRect(rect.x(), northHeight, rect.width(),
                                      item->sizeHint().height()));

              northHeight += item->geometry().height() + spacing();
          } else if (position == South) {
              item->setGeometry(QRect(item->geometry().x(),
                                      item->geometry().y(), rect.width(),
                                      item->sizeHint().height()));

              southHeight += item->geometry().height() + spacing();

              item->setGeometry(QRect(rect.x(),
                                rect.y() + rect.height() - southHeight + spacing(),
                                item->geometry().width(),
                                item->geometry().height()));
          } else if (position == Center) {
              center = wrapper;
          }
      }

      centerHeight = rect.height() - northHeight - southHeight;

      for (i = 0; i < list.size(); ++i) {
          ItemWrapper *wrapper = list.at(i);
          QLayoutItem *item = wrapper->item;
          Position position = wrapper->position;

          if (position == West) {
              item->setGeometry(QRect(rect.x() + westWidth, northHeight,
                                      item->sizeHint().width(), centerHeight));

              westWidth += item->geometry().width() + spacing();
          } else if (position == East) {
              item->setGeometry(QRect(item->geometry().x(), item->geometry().y(),
                                      item->sizeHint().width(), centerHeight));

              eastWidth += item->geometry().width() + spacing();

              item->setGeometry(QRect(
                                rect.x() + rect.width() - eastWidth + spacing(),
                                northHeight, item->geometry().width(),
                                item->geometry().height()));
          }
      }

      if (center)
          center->item->setGeometry(QRect(westWidth, northHeight,
                                          rect.width() - eastWidth - westWidth,
                                          centerHeight));
  }

  QSize BorderLayout::sizeHint() const
  {
      return calculateSize(SizeHint);
  }

  QLayoutItem *BorderLayout::takeAt(int index)
  {
      if (index >= 0 && index < list.size()) {
          ItemWrapper *layoutStruct = list.takeAt(index);
          return layoutStruct->item;
      }
      return 0;
  }

  void BorderLayout::add(QLayoutItem *item, Position position)
  {
      list.append(new ItemWrapper(item, position));
  }

  QSize BorderLayout::calculateSize(SizeType sizeType) const
  {
      QSize totalSize;

      for (int i = 0; i < list.size(); ++i) {
          ItemWrapper *wrapper = list.at(i);
          Position position = wrapper->position;
          QSize itemSize;

          if (sizeType == MinimumSize)
              itemSize = wrapper->item->minimumSize();
          else // (sizeType == SizeHint)
              itemSize = wrapper->item->sizeHint();

          if (position == North || position == South || position == Center)
              totalSize.rheight() += itemSize.height();

          if (position == West || position == East || position == Center)
              totalSize.rwidth() += itemSize.width();
      }
      return totalSize;
  }