--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/graphicsview/flowlayout/flowlayout.cpp Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,214 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "flowlayout.h"
+#include <QtGui/qwidget.h>
+#include <QtCore/qmath.h>
+
+FlowLayout::FlowLayout()
+{
+ m_spacing[0] = 6;
+ m_spacing[1] = 6;
+ QSizePolicy sp = sizePolicy();
+ sp.setHeightForWidth(true);
+ setSizePolicy(sp);
+}
+
+void FlowLayout::insertItem(int index, QGraphicsLayoutItem *item)
+{
+ item->setParentLayoutItem(this);
+ if (uint(index) > uint(m_items.count()))
+ index = m_items.count();
+ m_items.insert(index, item);
+ invalidate();
+}
+
+int FlowLayout::count() const
+{
+ return m_items.count();
+}
+
+QGraphicsLayoutItem *FlowLayout::itemAt(int index) const
+{
+ return m_items.value(index);
+}
+
+void FlowLayout::removeAt(int index)
+{
+ m_items.removeAt(index);
+ invalidate();
+}
+
+qreal FlowLayout::spacing(Qt::Orientation o) const
+{
+ return m_spacing[int(o) - 1];
+}
+
+void FlowLayout::setSpacing(Qt::Orientations o, qreal spacing)
+{
+ if (o & Qt::Horizontal)
+ m_spacing[0] = spacing;
+ if (o & Qt::Vertical)
+ m_spacing[1] = spacing;
+}
+
+void FlowLayout::setGeometry(const QRectF &geom)
+{
+ QGraphicsLayout::setGeometry(geom);
+ doLayout(geom, true);
+}
+
+qreal FlowLayout::doLayout(const QRectF &geom, bool applyNewGeometry) const
+{
+ qreal left, top, right, bottom;
+ getContentsMargins(&left, &top, &right, &bottom);
+ const qreal maxw = geom.width() - left - right;
+
+ qreal x = 0;
+ qreal y = 0;
+ qreal maxRowHeight = 0;
+ QSizeF pref;
+ for (int i = 0; i < m_items.count(); ++i) {
+ QGraphicsLayoutItem *item = m_items.at(i);
+ pref = item->effectiveSizeHint(Qt::PreferredSize);
+ maxRowHeight = qMax(maxRowHeight, pref.height());
+
+ qreal next_x;
+ next_x = x + pref.width();
+ if (next_x > maxw) {
+ if (x == 0) {
+ pref.setWidth(maxw);
+ } else {
+ x = 0;
+ next_x = pref.width();
+ }
+ y += maxRowHeight + spacing(Qt::Vertical);
+ maxRowHeight = 0;
+ }
+
+ if (applyNewGeometry)
+ item->setGeometry(QRectF(QPointF(left + x, top + y), pref));
+ x = next_x + spacing(Qt::Horizontal);
+ }
+ maxRowHeight = qMax(maxRowHeight, pref.height());
+ return top + y + maxRowHeight + bottom;
+}
+
+QSizeF FlowLayout::minSize(const QSizeF &constraint) const
+{
+ QSizeF size(0, 0);
+ qreal left, top, right, bottom;
+ getContentsMargins(&left, &top, &right, &bottom);
+ if (constraint.width() >= 0) { // height for width
+ const qreal height = doLayout(QRectF(QPointF(0,0), constraint), false);
+ size = QSizeF(constraint.width(), height);
+ } else if (constraint.height() >= 0) { // width for height?
+ // not supported
+ } else {
+ QGraphicsLayoutItem *item;
+ foreach (item, m_items)
+ size = size.expandedTo(item->effectiveSizeHint(Qt::MinimumSize));
+ size += QSize(left + right, top + bottom);
+ }
+ return size;
+}
+
+QSizeF FlowLayout::prefSize() const
+{
+ qreal left, right;
+ getContentsMargins(&left, 0, &right, 0);
+
+ QGraphicsLayoutItem *item;
+ qreal maxh = 0;
+ qreal totalWidth = 0;
+ foreach (item, m_items) {
+ if (totalWidth > 0)
+ totalWidth += spacing(Qt::Horizontal);
+ QSizeF pref = item->effectiveSizeHint(Qt::PreferredSize);
+ totalWidth += pref.width();
+ maxh = qMax(maxh, pref.height());
+ }
+ maxh += spacing(Qt::Vertical);
+
+ const qreal goldenAspectRatio = 1.61803399;
+ qreal w = qSqrt(totalWidth * maxh * goldenAspectRatio) + left + right;
+
+ return minSize(QSizeF(w, -1));
+}
+
+QSizeF FlowLayout::maxSize() const
+{
+ QGraphicsLayoutItem *item;
+ qreal totalWidth = 0;
+ qreal totalHeight = 0;
+ foreach (item, m_items) {
+ if (totalWidth > 0)
+ totalWidth += spacing(Qt::Horizontal);
+ if (totalHeight > 0)
+ totalHeight += spacing(Qt::Vertical);
+ QSizeF pref = item->effectiveSizeHint(Qt::PreferredSize);
+ totalWidth += pref.width();
+ totalHeight += pref.height();
+ }
+
+ qreal left, top, right, bottom;
+ getContentsMargins(&left, &top, &right, &bottom);
+ return QSizeF(left + totalWidth + right, top + totalHeight + bottom);
+}
+
+QSizeF FlowLayout::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
+{
+ QSizeF sh = constraint;
+ switch (which) {
+ case Qt::PreferredSize:
+ sh = prefSize();
+ break;
+ case Qt::MinimumSize:
+ sh = minSize(constraint);
+ break;
+ case Qt::MaximumSize:
+ sh = maxSize();
+ break;
+ default:
+ break;
+ }
+ return sh;
+}