C++/Qt/QLayout

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extends QLayout to create border layout

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef BORDERLAYOUT_H
#define BORDERLAYOUT_H
#include <QLayout>
#include <QRect>
#include <QWidgetItem>
class BorderLayout : public QLayout
{
public:
    enum Position { West, North, South, East, Center };
    BorderLayout(QWidget *parent, int margin = 0, int spacing = -1);
    BorderLayout(int spacing = -1);
    ~BorderLayout();
    void addItem(QLayoutItem *item);
    void addWidget(QWidget *widget, Position position);
    Qt::Orientations expandingDirections() const;
    bool hasHeightForWidth() const;
    int count() const;
    QLayoutItem *itemAt(int index) const;
    QSize minimumSize() const;
    void setGeometry(const QRect &rect);
    QSize sizeHint() const;
    QLayoutItem *takeAt(int index);
    void add(QLayoutItem *item, Position position);
private:
    struct ItemWrapper
    {
  ItemWrapper(QLayoutItem *i, Position p) {
      item = i;
      position = p;
  }
  QLayoutItem *item;
  Position position;
    };
    enum SizeType { MinimumSize, SizeHint };
    QSize calculateSize(SizeType sizeType) const;
    QList<ItemWrapper *> list;
};
#endif



#include <QtGui>
#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;
}



#ifndef WINDOW_H
#define WINDOW_H
#include <QWidget>
QT_BEGIN_NAMESPACE
class QLabel;
QT_END_NAMESPACE
class Window : public QWidget
{
    Q_OBJECT
public:
    Window();
private:
    QLabel *createLabel(const QString &text);
};
#endif



#include <QtGui>
#include "borderlayout.h"
#include "window.h"
Window::Window()
{
    QTextBrowser *centralWidget = new QTextBrowser;
    centralWidget->setPlainText(tr("Central widget"));
    BorderLayout *layout = new BorderLayout;
    layout->addWidget(centralWidget, BorderLayout::Center);
    layout->addWidget(createLabel("North"), BorderLayout::North);
    layout->addWidget(createLabel("West"), BorderLayout::West);
    layout->addWidget(createLabel("East 1"), BorderLayout::East);
    layout->addWidget(createLabel("East 2") , BorderLayout::East);
    layout->addWidget(createLabel("South"), BorderLayout::South);
    setLayout(layout);
    setWindowTitle(tr("Border Layout"));
}
QLabel *Window::createLabel(const QString &text)
{
    QLabel *label = new QLabel(text);
    label->setFrameStyle(QFrame::Box | QFrame::Raised);
    return label;
}


#include <QApplication>
#include "window.h"
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Window window;
    window.show();
    return app.exec();
}


extends QLayout to create flow layout

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef FLOWLAYOUT_H
#define FLOWLAYOUT_H
#include <QLayout>
#include <QRect>
#include <QWidgetItem>
class FlowLayout : public QLayout
{
public:
    FlowLayout(QWidget *parent, int margin = -1, int hSpacing = -1, int vSpacing = -1);
    FlowLayout(int margin = -1, int hSpacing = -1, int vSpacing = -1);
    ~FlowLayout();
    void addItem(QLayoutItem *item);
    int horizontalSpacing() const;
    int verticalSpacing() const;
    Qt::Orientations expandingDirections() const;
    bool hasHeightForWidth() const;
    int heightForWidth(int) const;
    int count() const;
    QLayoutItem *itemAt(int index) const;
    QSize minimumSize() const;
    void setGeometry(const QRect &rect);
    QSize sizeHint() const;
    QLayoutItem *takeAt(int index);
private:
    int doLayout(const QRect &rect, bool testOnly) const;
    int smartSpacing(QStyle::PixelMetric pm) const;
    QList<QLayoutItem *> itemList;
    int m_hSpace;
    int m_vSpace;
};

#endif


#include <QtGui>
#include "flowlayout.h"
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);
}

FlowLayout::~FlowLayout()
{
    QLayoutItem *item;
    while ((item = takeAt(0)))
        delete item;
}

void FlowLayout::addItem(QLayoutItem *item)
{
    itemList.append(item);
}

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);
    }
}

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;
}

Qt::Orientations FlowLayout::expandingDirections() const
{
    return 0;
}

bool FlowLayout::hasHeightForWidth() const
{
    return true;
}
int FlowLayout::heightForWidth(int width) const
{
    int height = doLayout(QRect(0, 0, width, 0), true);
    return height;
}

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;
}

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;

    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 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();
    }
}





#ifndef WINDOW_H
#define WINDOW_H
#include <QWidget>
QT_BEGIN_NAMESPACE
class QLabel;
QT_END_NAMESPACE
class Window : public QWidget
{
    Q_OBJECT
public:
    Window();
};

#endif


#include <QtGui>
#include "flowlayout.h"
#include "window.h"
Window::Window()
{
    FlowLayout *flowLayout = new FlowLayout;
    flowLayout->addWidget(new QPushButton(tr("Short")));
    flowLayout->addWidget(new QPushButton(tr("Longer")));
    flowLayout->addWidget(new QPushButton(tr("Different text")));
    flowLayout->addWidget(new QPushButton(tr("More text")));
    flowLayout->addWidget(new QPushButton(tr("Even longer button text")));
    setLayout(flowLayout);
    setWindowTitle(tr("Flow Layout"));
}


#include <QApplication>
#include "window.h"
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Window window;
    window.show();
    return app.exec();
}