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diff --git a/doc/src/examples/basicgraphicslayouts.qdoc b/doc/src/examples/basicgraphicslayouts.qdoc deleted file mode 100644 index b7023cf9ca..0000000000 --- a/doc/src/examples/basicgraphicslayouts.qdoc +++ /dev/null @@ -1,164 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). -** Contact: http://www.qt-project.org/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** GNU Free Documentation License -** Alternatively, this file may be used under the terms of the GNU Free -** Documentation License version 1.3 as published by the Free Software -** Foundation and appearing in the file included in the packaging of -** this file. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms -** and conditions contained in a signed written agreement between you -** and Nokia. -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example graphicsview/basicgraphicslayouts - \title Basic Graphics Layouts Example - - The Basic Graphics Layouts example shows how to use the layout classes - in QGraphicsView: QGraphicsLinearLayout and QGraphicsGridLayout. - In addition to that it shows how to write your own custom layout item. - - \image basicgraphicslayouts-example.png Screenshot of the Basic Layouts Example - - \section1 Window Class Definition - - The \c Window class is a subclass of QGraphicsWidget. It has a - constructor with a QGraphicsWidget \a parent as its parameter. - - \snippet examples/graphicsview/basicgraphicslayouts/window.h 0 - - \section1 Window Class Implementation - - The constructor of \c Window instantiates a QGraphicsLinearLayout object, - \c windowLayout, with vertical orientation. We instantiate another - QGraphicsLinearLayout object, \c linear, whose parent is \c windowLayout. - Next, we create a \c LayoutItem object, \c item and add it to \c linear - with the \l{QGraphicsLinearLayout::}{addItem()} function. We also provide - \c item with a \l{QGraphicsLinearLayout::setStretchFactor()} - {stretchFactor}. - - \snippet examples/graphicsview/basicgraphicslayouts/window.cpp 0 - - We repeat the process: - - \list - \li create a new \c LayoutItem, - \li add the item \c linear, and - \li provide a stretch factor. - \endlist - - \snippet examples/graphicsview/basicgraphicslayouts/window.cpp 1 - - We then add \c linear to \c windowLayout, nesting two - QGraphicsLinearLayout objects. Apart from the QGraphicsLinearLayout, we - also use a QGraphicsGridLayout object, \c grid, which is a 4x3 grid with - some cells spanning to other rows. - - We create seven \c LayoutItem objects and place them into \c grid with - the \l{QGraphicsGridLayout::}{addItem()} function as shown in the code - snippet below: - - \snippet examples/graphicsview/basicgraphicslayouts/window.cpp 2 - - The first item we add to \c grid is placed in the top left cell, - spanning four rows. The next two items are placed in the second column, - and they span two rows. Each item's \l{QGraphicsWidget::}{maximumHeight()} - and \l{QGraphicsWidget::}{minimumHeight()} are set to be equal so that - they do not expand vertically. As a result, these items will not - fit vertically in their cells. So, we specify that they should be - vertically aligned in the center of the cell using Qt::AlignVCenter. - - Finally, \c grid itself is added to \c windowLayout. Unlike - QGridLayout::addItem(), QGraphicsGridLayout::addItem() requires a row - and a column for its argument, specifying which cell the item should be - positioned in. Also, if the \c rowSpan and \c columnSpan arguments - are omitted, they will default to 1. - - Note that we do not specify a parent for each \c LayoutItem that we - construct, as all these items will be added to \c windowLayout. When we - add an item to a layout, it will be automatically reparented to the widget - on which the layout is installed. - - \snippet examples/graphicsview/basicgraphicslayouts/window.cpp 3 - - Now that we have set up \c grid and added it to \c windowLayout, we - install \c windowLayout onto the window object using - QGraphicsWidget::setLayout() and we set the window title. - - \section1 LayoutItem Class Definition - - The \c LayoutItem class is a subclass of QGraphicsLayoutItem and - QGraphicsItem. It has a constructor, a destructor, and some required - reimplementations. - Since it inherits QGraphicsLayoutItem it must reimplement - {QGraphicsLayoutItem::setGeometry()}{setGeometry()} and - {QGraphicsLayoutItem::sizeHint()}{sizeHint()}. - In addition to that it inherits QGraphicsItem, so it must reimplement - {QGraphicsItem::boundingRect()}{boundingRect()} and - {QGraphicsItem::paint()}{paint()}. - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.h 0 - - The \c LayoutItem class also has a private instance of QPixmap, \c m_pix. - - \section1 LayoutItem Class Implementation - - In \c{LayoutItem}'s constructor, \c m_pix is instantiated and the - \c{block.png} image is loaded into it. - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.cpp 0 - - We use the Q_UNUSED() macro to prevent the compiler from generating - warnings regarding unused parameters. - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.cpp 1 - - The idea behind the \c paint() function is to paint the - background rect then paint a rect around the pixmap. - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.cpp 2 - - The reimplementation of \l{QGraphicsItem::}{boundingRect()} - will set the top left corner at (0,0), and the size of it will be - the size of the layout items - \l{QGraphicsLayoutItem::}{geometry()}. This is the area that - we paint within. - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.cpp 3 - - - The reimplementation of \l{QGraphicsLayoutItem::setGeometry()}{setGeometry()} - simply calls its baseclass implementation. However, since this will change - the boundingRect we must also call - \l{QGraphicsItem::prepareGeometryChange()}{prepareGeometryChange()}. - Finally, we move the item according to \c geom.topLeft(). - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.cpp 4 - - - Since we don't want the size of the item to be smaller than the pixmap, we - must make sure that we return a size hint that is larger than \c m_pix. - We also add some extra space around for borders that we will paint later. - Alternatively, you could scale the pixmap to prevent the item from - becoming smaller than the pixmap. - The preferred size is the same as the minimum size hint, while we set - maximum to be a large value - - \snippet examples/graphicsview/basicgraphicslayouts/layoutitem.cpp 5 - -*/
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