/******************************************************************************** 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."**** $QT_END_LICENSE$******************************************************************************/ #ifdef __GNUC__#pragma GCC diagnostic push#pragma GCC diagnostic ignored "-Wdouble-promotion"#endif #include <QtWidgets> #ifdef __GNUC__#pragma GCC diagnostic pop#endif #include "FlowLayout.h"//! [1]FlowLayout::FlowLayout(QWidget *parent, int margin, int hSpacing, int vSpacing)    : QLayout(parent), m_hSpace(hSpacing), m_vSpace(vSpacing){    setContentsMargins(margin, margin, margin, margin);} FlowLayout::FlowLayout(int margin, int hSpacing, int vSpacing)    : m_hSpace(hSpacing), m_vSpace(vSpacing){    setContentsMargins(margin, margin, margin, margin);}//! [1] //! [2]FlowLayout::~FlowLayout(){    QLayoutItem *item;    while ((item = takeAt(0)))        delete item;}//! [2] //! [3]void FlowLayout::addItem(QLayoutItem *item){    itemList.append(item);}//! [3] //! [4]int FlowLayout::horizontalSpacing() const{    if (m_hSpace >= 0) {        return m_hSpace;    } else {        return smartSpacing(QStyle::PM_LayoutHorizontalSpacing);    }} int FlowLayout::verticalSpacing() const{    if (m_vSpace >= 0) {        return m_vSpace;    } else {        return smartSpacing(QStyle::PM_LayoutVerticalSpacing);    }}//! [4] //! [5]int FlowLayout::count() const{    return itemList.size();} QLayoutItem *FlowLayout::itemAt(int index) const{    return itemList.value(index);} QLayoutItem *FlowLayout::takeAt(int index){    if (index >= 0 && index < itemList.size())        return itemList.takeAt(index);    else        return 0;}//! [5] //! [6]Qt::Orientations FlowLayout::expandingDirections() const{    return 0;}//! [6] //! [7]bool FlowLayout::hasHeightForWidth() const{    return true;} int FlowLayout::heightForWidth(int width) const{    int height = doLayout(QRect(0, 0, width, 0), true);    return height;}//! [7] //! [8]void FlowLayout::setGeometry(const QRect &rect){    QLayout::setGeometry(rect);    doLayout(rect, false);} QSize FlowLayout::sizeHint() const{    return minimumSize();} QSize FlowLayout::minimumSize() const{    QSize size;    QLayoutItem *item;    foreach (item, itemList)        size = size.expandedTo(item->minimumSize());     size += QSize(2*margin(), 2*margin());    return size;}//! [8] //! [9]int FlowLayout::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;//! [9] //! [10]    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);//! [10]//! [11]        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;}//! [11]//! [12]int FlowLayout::smartSpacing(QStyle::PixelMetric pm) const{    QObject *parent = this->parent();    if (!parent) {        return -1;    } else if (parent->isWidgetType()) {        QWidget *pw = static_cast<QWidget *>(parent);        return pw->style()->pixelMetric(pm, 0, pw);    } else {        return static_cast<QLayout *>(parent)->spacing();    }}//! [12]