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Diffstat (limited to 'src/gui/graphicsview/qgraphicslayout.cpp')
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diff --git a/src/gui/graphicsview/qgraphicslayout.cpp b/src/gui/graphicsview/qgraphicslayout.cpp deleted file mode 100644 index 904a3deda2..0000000000 --- a/src/gui/graphicsview/qgraphicslayout.cpp +++ /dev/null @@ -1,451 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). -** All rights reserved. -** Contact: Nokia Corporation (qt-info@nokia.com) -** -** This file is part of the QtGui module 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 "qapplication.h" - -#ifndef QT_NO_GRAPHICSVIEW -#include "qgraphicslayout.h" -#include "qgraphicslayout_p.h" -#include "qgraphicslayoutitem.h" -#include "qgraphicslayoutitem_p.h" -#include "qgraphicswidget.h" -#include "qgraphicswidget_p.h" -#include "qgraphicsscene.h" - -QT_BEGIN_NAMESPACE - -/*! - \class QGraphicsLayout - \brief The QGraphicsLayout class provides the base class for all layouts - in Graphics View. - \since 4.4 - \ingroup graphicsview-api - - QGraphicsLayout is an abstract class that defines a virtual API for - arranging QGraphicsWidget children and other QGraphicsLayoutItem objects - for a QGraphicsWidget. QGraphicsWidget assigns responsibility to a - QGraphicsLayout through QGraphicsWidget::setLayout(). As the widget - is resized, the layout will automatically arrange the widget's children. - QGraphicsLayout inherits QGraphicsLayoutItem, so, it can be managed by - any layout, including its own subclasses. - - \section1 Writing a Custom Layout - - You can use QGraphicsLayout as a base to write your own custom layout - (e.g., a flowlayout), but it is more common to use one of its subclasses - instead - QGraphicsLinearLayout or QGraphicsGridLayout. When creating - a custom layout, the following functions must be reimplemented as a bare - minimum: - - \table - \header \o Function \o Description - \row \o QGraphicsLayoutItem::setGeometry() - \o Notifies you when the geometry of the layout is set. You can - store the geometry in your own layout class in a reimplementation - of this function. - \row \o QGraphicsLayoutItem::sizeHint() - \o Returns the layout's size hints. - \row \o QGraphicsLayout::count() - \o Returns the number of items in your layout. - \row \o QGraphicsLayout::itemAt() - \o Returns a pointer to an item in your layout. - \row \o QGraphicsLayout::removeAt() - \o Removes an item from your layout without destroying it. - \endtable - - For more details on how to implement each function, refer to the individual - function documentation. - - Each layout defines its own API for arranging widgets and layout items. - For example, with a grid layout, you require a row and a - column index with optional row and column spans, alignment, spacing, and more. - A linear layout, however, requires a single row or column index to position its - items. For a grid layout, the order of insertion does not affect the layout in - any way, but for a linear layout, the order is essential. When writing your own - layout subclass, you are free to choose the API that best suits your layout. - - \section1 Activating the Layout - - When the layout's geometry changes, QGraphicsLayout immediately rearranges - all of its managed items by calling setGeometry() on each item. This - rearrangement is called \e activating the layout. - - QGraphicsLayout updates its own geometry to match the contentsRect() of the - QGraphicsLayoutItem it is managing. Thus, it will automatically rearrange all - its items when the widget is resized. QGraphicsLayout caches the sizes of all - its managed items to avoid calling setGeometry() too often. - - \note A QGraphicsLayout will have the same geometry as the contentsRect() - of the widget (not the layout) it is assigned to. - - \section2 Activating the Layout Implicitly - - The layout can be activated implicitly using one of two ways: by calling - activate() or by calling invalidate(). Calling activate() activates the layout - immediately. In contrast, calling invalidate() is delayed, as it posts a - \l{QEvent::LayoutRequest}{LayoutRequest} event to the managed widget. Due - to event compression, the activate() will only be called once after control has - returned to the event loop. This is referred to as \e invalidating the layout. - Invalidating the layout also invalidates any cached information. Also, the - invalidate() function is a virtual function. So, you can invalidate your own - cache in a subclass of QGraphicsLayout by reimplementing this function. - - \section1 Event Handling - - QGraphicsLayout listens to events for the widget it manages through the - virtual widgetEvent() event handler. When the layout is assigned to a - widget, all events delivered to the widget are first processed by - widgetEvent(). This allows the layout to be aware of any relevant state - changes on the widget such as visibility changes or layout direction changes. - - \section1 Margin Handling - - The margins of a QGraphicsLayout can be modified by reimplementing - setContentsMargins() and getContentsMargins(). - -*/ - -/*! - Contructs a QGraphicsLayout object. - - \a parent is passed to QGraphicsLayoutItem's constructor and the - QGraphicsLayoutItem's isLayout argument is set to \e true. - - If \a parent is a QGraphicsWidget the layout will be installed - on that widget. (Note that installing a layout will delete the old one - installed.) -*/ -QGraphicsLayout::QGraphicsLayout(QGraphicsLayoutItem *parent) - : QGraphicsLayoutItem(*new QGraphicsLayoutPrivate) -{ - setParentLayoutItem(parent); - if (parent && !parent->isLayout()) { - // If a layout has a parent that is not a layout it must be a QGraphicsWidget. - QGraphicsItem *itemParent = parent->graphicsItem(); - if (itemParent && itemParent->isWidget()) { - static_cast<QGraphicsWidget *>(itemParent)->d_func()->setLayout_helper(this); - } else { - qWarning("QGraphicsLayout::QGraphicsLayout: Attempt to create a layout with a parent that is" - " neither a QGraphicsWidget nor QGraphicsLayout"); - } - } - setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding, QSizePolicy::DefaultType); - setOwnedByLayout(true); -} - -/*! - \internal -*/ -QGraphicsLayout::QGraphicsLayout(QGraphicsLayoutPrivate &dd, QGraphicsLayoutItem *parent) - : QGraphicsLayoutItem(dd) -{ - setParentLayoutItem(parent); - if (parent && !parent->isLayout()) { - // If a layout has a parent that is not a layout it must be a QGraphicsWidget. - QGraphicsItem *itemParent = parent->graphicsItem(); - if (itemParent && itemParent->isWidget()) { - static_cast<QGraphicsWidget *>(itemParent)->d_func()->setLayout_helper(this); - } else { - qWarning("QGraphicsLayout::QGraphicsLayout: Attempt to create a layout with a parent that is" - " neither a QGraphicsWidget nor QGraphicsLayout"); - } - } - setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding, QSizePolicy::DefaultType); - setOwnedByLayout(true); -} - -/*! - Destroys the QGraphicsLayout object. -*/ -QGraphicsLayout::~QGraphicsLayout() -{ -} - -/*! - Sets the contents margins to \a left, \a top, \a right and \a bottom. The - default contents margins for toplevel layouts are style dependent - (by querying the pixelMetric for QStyle::PM_LayoutLeftMargin, - QStyle::PM_LayoutTopMargin, QStyle::PM_LayoutRightMargin and - QStyle::PM_LayoutBottomMargin). - - For sublayouts the default margins are 0. - - Changing the contents margins automatically invalidates the layout. - - \sa invalidate() -*/ -void QGraphicsLayout::setContentsMargins(qreal left, qreal top, qreal right, qreal bottom) -{ - Q_D(QGraphicsLayout); - if (d->left == left && d->top == top && d->right == right && d->bottom == bottom) - return; - d->left = left; - d->right = right; - d->top = top; - d->bottom = bottom; - invalidate(); -} - -/*! - \reimp -*/ -void QGraphicsLayout::getContentsMargins(qreal *left, qreal *top, qreal *right, qreal *bottom) const -{ - Q_D(const QGraphicsLayout); - d->getMargin(left, d->left, QStyle::PM_LayoutLeftMargin); - d->getMargin(top, d->top, QStyle::PM_LayoutTopMargin); - d->getMargin(right, d->right, QStyle::PM_LayoutRightMargin); - d->getMargin(bottom, d->bottom, QStyle::PM_LayoutBottomMargin); -} - -/*! - Activates the layout, causing all items in the layout to be immediately - rearranged. This function is based on calling count() and itemAt(), and - then calling setGeometry() on all items sequentially. When activated, - the layout will adjust its geometry to its parent's contentsRect(). - The parent will then invalidate any layout of its own. - - If called in sequence or recursively, e.g., by one of the arranged items - in response to being resized, this function will do nothing. - - Note that the layout is free to use geometry caching to optimize this - process. To forcefully invalidate any such cache, you can call - invalidate() before calling activate(). - - \sa invalidate() -*/ -void QGraphicsLayout::activate() -{ - Q_D(QGraphicsLayout); - if (d->activated) - return; - - d->activateRecursive(this); - - // we don't call activate on a sublayout, but somebody might. - // Therefore, we walk to the parentitem of the toplevel layout. - QGraphicsLayoutItem *parentItem = this; - while (parentItem && parentItem->isLayout()) - parentItem = parentItem->parentLayoutItem(); - if (!parentItem) - return; - Q_ASSERT(!parentItem->isLayout()); - - setGeometry(parentItem->contentsRect()); // relayout children - - // ### bug, should be parentItem ? - parentLayoutItem()->updateGeometry(); // bubble up; will set activated to false - // ### too many resizes? maybe we should walk up the chain to the - // ### top-level layouted layoutItem and call activate there. -} - -/*! - Returns true if the layout is currently being activated; otherwise, - returns false. If the layout is being activated, this means that it is - currently in the process of rearranging its items (i.e., the activate() - function has been called, and has not yet returned). - - \sa activate(), invalidate() -*/ -bool QGraphicsLayout::isActivated() const -{ - Q_D(const QGraphicsLayout); - return d->activated; -} - -/*! - Clears any cached geometry and size hint information in the layout, and - posts a \l{QEvent::LayoutRequest}{LayoutRequest} event to the managed - parent QGraphicsLayoutItem. - - \sa activate(), setGeometry() -*/ -void QGraphicsLayout::invalidate() -{ - // only mark layouts as invalid (activated = false) if we can post a LayoutRequest event. - QGraphicsLayoutItem *layoutItem = this; - while (layoutItem && layoutItem->isLayout()) { - // we could call updateGeometry(), but what if that method - // does not call the base implementation? In addition, updateGeometry() - // does more than we need. - layoutItem->d_func()->sizeHintCacheDirty = true; - layoutItem->d_func()->sizeHintWithConstraintCacheDirty = true; - layoutItem = layoutItem->parentLayoutItem(); - } - if (layoutItem) { - layoutItem->d_func()->sizeHintCacheDirty = true; - layoutItem->d_func()->sizeHintWithConstraintCacheDirty = true; - } - - bool postIt = layoutItem ? !layoutItem->isLayout() : false; - if (postIt) { - layoutItem = this; - while (layoutItem && layoutItem->isLayout() - && static_cast<QGraphicsLayout*>(layoutItem)->d_func()->activated) { - static_cast<QGraphicsLayout*>(layoutItem)->d_func()->activated = false; - layoutItem = layoutItem->parentLayoutItem(); - } - if (layoutItem && !layoutItem->isLayout()) { - // If a layout has a parent that is not a layout it must be a QGraphicsWidget. - QApplication::postEvent(static_cast<QGraphicsWidget *>(layoutItem), new QEvent(QEvent::LayoutRequest)); - } - } -} - -/*! - \reimp -*/ -void QGraphicsLayout::updateGeometry() -{ - QGraphicsLayoutItem::updateGeometry(); - if (QGraphicsLayoutItem *parentItem = parentLayoutItem()) { - if (parentItem->isLayout()) { - parentItem->updateGeometry(); - } else { - invalidate(); - } - } -} - -/*! - This virtual event handler receives all events for the managed - widget. QGraphicsLayout uses this event handler to listen for layout - related events such as geometry changes, layout changes or layout - direction changes. - - \a e is a pointer to the event. - - You can reimplement this event handler to track similar events for your - own custom layout. - - \sa QGraphicsWidget::event(), QGraphicsItem::sceneEvent() -*/ -void QGraphicsLayout::widgetEvent(QEvent *e) -{ - switch (e->type()) { - case QEvent::GraphicsSceneResize: - if (isActivated()) { - setGeometry(parentLayoutItem()->contentsRect()); - } else { - activate(); // relies on that activate() will call updateGeometry() - } - break; - case QEvent::LayoutRequest: - activate(); - break; - case QEvent::LayoutDirectionChange: - invalidate(); - break; - default: - break; - } -} - -/*! - \fn virtual int QGraphicsLayout::count() const = 0 - - This pure virtual function must be reimplemented in a subclass of - QGraphicsLayout to return the number of items in the layout. - - The subclass is free to decide how to store the items. - - \sa itemAt(), removeAt() -*/ - -/*! - \fn virtual QGraphicsLayoutItem *QGraphicsLayout::itemAt(int i) const = 0 - - This pure virtual function must be reimplemented in a subclass of - QGraphicsLayout to return a pointer to the item at index \a i. The - reimplementation can assume that \a i is valid (i.e., it respects the - value of count()). - Together with count(), it is provided as a means of iterating over all items in a layout. - - The subclass is free to decide how to store the items, and the visual arrangement - does not have to be reflected through this function. - - \sa count(), removeAt() -*/ - -/*! - \fn virtual void QGraphicsLayout::removeAt(int index) = 0 - - This pure virtual function must be reimplemented in a subclass of - QGraphicsLayout to remove the item at \a index. The - reimplementation can assume that \a index is valid (i.e., it - respects the value of count()). - - The implementation must ensure that the parentLayoutItem() of - the removed item does not point to this layout, since the item is - considered to be removed from the layout hierarchy. - - If the layout is to be reused between applications, we recommend - that the layout deletes the item, but the graphics view framework - does not depend on this. - - The subclass is free to decide how to store the items. - - \sa itemAt(), count() -*/ - -/*! - \since 4.6 - - This function is a convenience function provided for custom layouts, and will go through - all items in the layout and reparent their graphics items to the closest QGraphicsWidget - ancestor of the layout. - - If \a layoutItem is already in a different layout, it will be removed from that layout. - - If custom layouts want special behaviour they can ignore to use this function, and implement - their own behaviour. - - \sa graphicsItem() - */ -void QGraphicsLayout::addChildLayoutItem(QGraphicsLayoutItem *layoutItem) -{ - Q_D(QGraphicsLayout); - d->addChildLayoutItem(layoutItem); -} - -QT_END_NAMESPACE - -#endif //QT_NO_GRAPHICSVIEW |