text: /****************************************************************************
  **
  ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
  ** Contact: http://www.qt-project.org/legal
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** You may use this file under the terms of the BSD license as follows:
  **
  ** "Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
  ** met:
  **   * Redistributions of source code must retain the above copyright
  **     notice, this list of conditions and the following disclaimer.
  **   * Redistributions in binary form must reproduce the above copyright
  **     notice, this list of conditions and the following disclaimer in
  **     the documentation and/or other materials provided with the
  **     distribution.
  **   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
  **     of its contributors may be used to endorse or promote products derived
  **     from this software without specific prior written permission.
  **
  **
  ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/
  
  #if defined(__GNUC__) && (__GNUC__ == 4 && __GNUC_MINOR__ < 6) && !defined(__clang__)
  #  pragma message "Disabling GCC float equality comparison warnings via pragma due to Qt headers..."
  #endif
  #if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) && !defined(__clang__)
  #  pragma GCC diagnostic push
  #endif
  #if defined(__clang__)
  #  pragma clang diagnostic push
  #endif
  #if defined(__GNUC__) && (__GNUC__ == 4 && __GNUC_MINOR__ >= 3) && !defined(__clang__)
  #  pragma GCC diagnostic ignored "-Wfloat-equal"
  #endif
  #if defined(__clang__)
  #  pragma clang diagnostic ignored "-Wfloat-equal"
  #endif
  #undef Success
  #include <QWidget>
  #undef Success
  #include <QLayout>
  #undef Success
  #include <QLayoutItem>
  #undef Success
  #include <QStyle>
  #if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) && !defined(__clang__)
  #  pragma GCC diagnostic pop
  #endif
  #if defined(__clang__)
  #  pragma clang diagnostic pop
  #endif
  
  #include "QFlowLayout.h"
  
  QFlowLayout::QFlowLayout(QWidget *pparent, int mmargin, int hSpacing, int vSpacing)
      : QLayout(pparent), m_hSpace(hSpacing), m_vSpace(vSpacing)
  {
      setContentsMargins(mmargin, mmargin, mmargin, mmargin);
  }
  
  QFlowLayout::QFlowLayout(int mmargin, int hSpacing, int vSpacing)
      : m_hSpace(hSpacing), m_vSpace(vSpacing)
  {
      setContentsMargins(mmargin, mmargin, mmargin, mmargin);
  }
  
  QFlowLayout::~QFlowLayout()
  {
      QLayoutItem *item;
      while ((item = takeAt(0)))
          delete item;
  }
  
  void QFlowLayout::addItem(QLayoutItem *item)
  {
      itemList.append(item);
  }
  
  int QFlowLayout::horizontalSpacing() const
  {
      if (m_hSpace >= 0) {
          return m_hSpace;
      } else {
          return smartSpacing(QStyle::PM_LayoutHorizontalSpacing);
      }
  }
  
  int QFlowLayout::verticalSpacing() const
  {
      if (m_vSpace >= 0) {
          return m_vSpace;
      } else {
          return smartSpacing(QStyle::PM_LayoutVerticalSpacing);
      }
  }
  
  void QFlowLayout::setHorizontalSpacing(int hspacing)
  {
      m_hSpace = hspacing;
  }
  
  void QFlowLayout::setVerticalSpacing(int vspacing)
  {
      m_vSpace = vspacing;
  }
  
  int QFlowLayout::count() const
  {
      return itemList.size();
  }
  
  QLayoutItem *QFlowLayout::itemAt(int index) const
  {
      return itemList.value(index);
  }
  
  QLayoutItem *QFlowLayout::takeAt(int index)
  {
      if (index >= 0 && index < itemList.size())
          return itemList.takeAt(index);
      else
          return 0;
  }
  
  Qt::Orientations QFlowLayout::expandingDirections() const
  {
      return Qt::Orientations{};
  }
  
  bool QFlowLayout::hasHeightForWidth() const
  {
      return true;
  }
  
  int QFlowLayout::heightForWidth(int width) const
  {
      int height = doLayout(QRect(0, 0, width, 0), true);
      return height;
  }
  
  void QFlowLayout::setGeometry(const QRect &rect)
  {
      QLayout::setGeometry(rect);
      doLayout(rect, false);
  }
  
  QSize QFlowLayout::sizeHint() const
  {
      return minimumSize();
  }
  
  QSize QFlowLayout::minimumSize() const
  {
      QSize size;
      QLayoutItem *item;
      foreach (item, itemList)
          size = size.expandedTo(item->minimumSize());
  
      size += QSize(2*margin(), 2*margin());
      return size;
  }
  
  int QFlowLayout::doLayout(const QRect &rect, bool testOnly) const
  {
      int left, top, right, bottom;
      getContentsMargins(&left, &top, &right, &bottom);
      QRect effectiveRect = rect.adjusted(+left, +top, -right, -bottom);
      int x = effectiveRect.x();
      int y = effectiveRect.y();
      int lineHeight = 0;
  
      QLayoutItem *item;
      foreach (item, itemList) {
          QWidget *wid = item->widget();
          int spaceX = horizontalSpacing();
          if (spaceX == -1)
              spaceX = wid->style()->layoutSpacing(
                  QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Horizontal);
          int spaceY = verticalSpacing();
          if (spaceY == -1)
              spaceY = wid->style()->layoutSpacing(
                  QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Vertical);
          int nextX = x + item->sizeHint().width() + spaceX;
          if (nextX - spaceX > effectiveRect.right() && lineHeight > 0) {
              x = effectiveRect.x();
              y = y + lineHeight + spaceY;
              nextX = x + item->sizeHint().width() + spaceX;
              lineHeight = 0;
          }
  
          if (!testOnly)
              item->setGeometry(QRect(QPoint(x, y), item->sizeHint()));
  
          x = nextX;
          lineHeight = qMax(lineHeight, item->sizeHint().height());
      }
      return y + lineHeight - rect.y() + bottom;
  }
  int QFlowLayout::smartSpacing(QStyle::PixelMetric pm) const
  {
      QObject *pparent = this->parent();
      if (!pparent) {
          return -1;
      } else if (pparent->isWidgetType()) {
          QWidget *pw = static_cast<QWidget *>(pparent);
          return pw->style()->pixelMetric(pm, 0, pw);
      } else {
          return static_cast<QLayout *>(pparent)->spacing();
      }
  }
  