<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>flowlayout.cpp Example File | Qt Widgets 5.12.2</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtwidgets-index.html">Qt Widgets</a></td><td ><a href="qtwidgets-layouts-flowlayout-example.html">Flow Layout Example</a></td><td >flowlayout.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtwidgets-index.html">Qt 5.12.2 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">flowlayout.cpp Example File</h1> <span class="subtitle">layouts/flowlayout/flowlayout.cpp</span> <!-- $$$layouts/flowlayout/flowlayout.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, 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 The Qt Company Ltd 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." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include <QtWidgets></span> <span class="preprocessor">#include "flowlayout.h"</span> FlowLayout<span class="operator">::</span>FlowLayout(<span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent<span class="operator">,</span> <span class="type">int</span> margin<span class="operator">,</span> <span class="type">int</span> hSpacing<span class="operator">,</span> <span class="type">int</span> vSpacing) : <span class="type"><a href="qlayout.html">QLayout</a></span>(parent)<span class="operator">,</span> m_hSpace(hSpacing)<span class="operator">,</span> m_vSpace(vSpacing) { setContentsMargins(margin<span class="operator">,</span> margin<span class="operator">,</span> margin<span class="operator">,</span> margin); } FlowLayout<span class="operator">::</span>FlowLayout(<span class="type">int</span> margin<span class="operator">,</span> <span class="type">int</span> hSpacing<span class="operator">,</span> <span class="type">int</span> vSpacing) : m_hSpace(hSpacing)<span class="operator">,</span> m_vSpace(vSpacing) { setContentsMargins(margin<span class="operator">,</span> margin<span class="operator">,</span> margin<span class="operator">,</span> margin); } FlowLayout<span class="operator">::</span><span class="operator">~</span>FlowLayout() { <span class="type"><a href="qlayoutitem.html">QLayoutItem</a></span> <span class="operator">*</span>item; <span class="keyword">while</span> ((item <span class="operator">=</span> takeAt(<span class="number">0</span>))) <span class="keyword">delete</span> item; } <span class="type">void</span> FlowLayout<span class="operator">::</span>addItem(<span class="type"><a href="qlayoutitem.html">QLayoutItem</a></span> <span class="operator">*</span>item) { itemList<span class="operator">.</span>append(item); } <span class="type">int</span> FlowLayout<span class="operator">::</span>horizontalSpacing() <span class="keyword">const</span> { <span class="keyword">if</span> (m_hSpace <span class="operator">></span><span class="operator">=</span> <span class="number">0</span>) { <span class="keyword">return</span> m_hSpace; } <span class="keyword">else</span> { <span class="keyword">return</span> smartSpacing(<span class="type"><a href="qstyle.html">QStyle</a></span><span class="operator">::</span>PM_LayoutHorizontalSpacing); } } <span class="type">int</span> FlowLayout<span class="operator">::</span>verticalSpacing() <span class="keyword">const</span> { <span class="keyword">if</span> (m_vSpace <span class="operator">></span><span class="operator">=</span> <span class="number">0</span>) { <span class="keyword">return</span> m_vSpace; } <span class="keyword">else</span> { <span class="keyword">return</span> smartSpacing(<span class="type"><a href="qstyle.html">QStyle</a></span><span class="operator">::</span>PM_LayoutVerticalSpacing); } } <span class="type">int</span> FlowLayout<span class="operator">::</span>count() <span class="keyword">const</span> { <span class="keyword">return</span> itemList<span class="operator">.</span>size(); } <span class="type"><a href="qlayoutitem.html">QLayoutItem</a></span> <span class="operator">*</span>FlowLayout<span class="operator">::</span>itemAt(<span class="type">int</span> index) <span class="keyword">const</span> { <span class="keyword">return</span> itemList<span class="operator">.</span>value(index); } <span class="type"><a href="qlayoutitem.html">QLayoutItem</a></span> <span class="operator">*</span>FlowLayout<span class="operator">::</span>takeAt(<span class="type">int</span> index) { <span class="keyword">if</span> (index <span class="operator">></span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> index <span class="operator"><</span> itemList<span class="operator">.</span>size()) <span class="keyword">return</span> itemList<span class="operator">.</span>takeAt(index); <span class="keyword">else</span> <span class="keyword">return</span> <span class="number">0</span>; } <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Orientations FlowLayout<span class="operator">::</span>expandingDirections() <span class="keyword">const</span> { <span class="keyword">return</span> <span class="number">0</span>; } bool FlowLayout<span class="operator">::</span>hasHeightForWidth() <span class="keyword">const</span> { <span class="keyword">return</span> <span class="keyword">true</span>; } <span class="type">int</span> FlowLayout<span class="operator">::</span>heightForWidth(<span class="type">int</span> width) <span class="keyword">const</span> { <span class="type">int</span> height <span class="operator">=</span> doLayout(<span class="type"><a href="../qtcore/qrect.html">QRect</a></span>(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> width<span class="operator">,</span> <span class="number">0</span>)<span class="operator">,</span> <span class="keyword">true</span>); <span class="keyword">return</span> height; } <span class="type">void</span> FlowLayout<span class="operator">::</span>setGeometry(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qrect.html">QRect</a></span> <span class="operator">&</span>rect) { <span class="type"><a href="qlayout.html">QLayout</a></span><span class="operator">::</span>setGeometry(rect); doLayout(rect<span class="operator">,</span> <span class="keyword">false</span>); } <span class="type"><a href="../qtcore/qsize.html">QSize</a></span> FlowLayout<span class="operator">::</span>sizeHint() <span class="keyword">const</span> { <span class="keyword">return</span> minimumSize(); } <span class="type"><a href="../qtcore/qsize.html">QSize</a></span> FlowLayout<span class="operator">::</span>minimumSize() <span class="keyword">const</span> { <span class="type"><a href="../qtcore/qsize.html">QSize</a></span> size; <span class="type"><a href="qlayoutitem.html">QLayoutItem</a></span> <span class="operator">*</span>item; foreach (item<span class="operator">,</span> itemList) size <span class="operator">=</span> size<span class="operator">.</span>expandedTo(item<span class="operator">-</span><span class="operator">></span>minimumSize()); size <span class="operator">+</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qsize.html">QSize</a></span>(<span class="number">2</span><span class="operator">*</span>margin()<span class="operator">,</span> <span class="number">2</span><span class="operator">*</span>margin()); <span class="keyword">return</span> size; } <span class="type">int</span> FlowLayout<span class="operator">::</span>doLayout(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qrect.html">QRect</a></span> <span class="operator">&</span>rect<span class="operator">,</span> bool testOnly) <span class="keyword">const</span> { <span class="type">int</span> left<span class="operator">,</span> top<span class="operator">,</span> right<span class="operator">,</span> bottom; getContentsMargins(<span class="operator">&</span>left<span class="operator">,</span> <span class="operator">&</span>top<span class="operator">,</span> <span class="operator">&</span>right<span class="operator">,</span> <span class="operator">&</span>bottom); <span class="type"><a href="../qtcore/qrect.html">QRect</a></span> effectiveRect <span class="operator">=</span> rect<span class="operator">.</span>adjusted(<span class="operator">+</span>left<span class="operator">,</span> <span class="operator">+</span>top<span class="operator">,</span> <span class="operator">-</span>right<span class="operator">,</span> <span class="operator">-</span>bottom); <span class="type">int</span> x <span class="operator">=</span> effectiveRect<span class="operator">.</span>x(); <span class="type">int</span> y <span class="operator">=</span> effectiveRect<span class="operator">.</span>y(); <span class="type">int</span> lineHeight <span class="operator">=</span> <span class="number">0</span>; <span class="type"><a href="qlayoutitem.html">QLayoutItem</a></span> <span class="operator">*</span>item; foreach (item<span class="operator">,</span> itemList) { <span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>wid <span class="operator">=</span> item<span class="operator">-</span><span class="operator">></span>widget(); <span class="type">int</span> spaceX <span class="operator">=</span> horizontalSpacing(); <span class="keyword">if</span> (spaceX <span class="operator">=</span><span class="operator">=</span> <span class="operator">-</span><span class="number">1</span>) spaceX <span class="operator">=</span> wid<span class="operator">-</span><span class="operator">></span>style()<span class="operator">-</span><span class="operator">></span>layoutSpacing( <span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>PushButton<span class="operator">,</span> <span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>PushButton<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Horizontal); <span class="type">int</span> spaceY <span class="operator">=</span> verticalSpacing(); <span class="keyword">if</span> (spaceY <span class="operator">=</span><span class="operator">=</span> <span class="operator">-</span><span class="number">1</span>) spaceY <span class="operator">=</span> wid<span class="operator">-</span><span class="operator">></span>style()<span class="operator">-</span><span class="operator">></span>layoutSpacing( <span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>PushButton<span class="operator">,</span> <span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>PushButton<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Vertical); <span class="type">int</span> nextX <span class="operator">=</span> x <span class="operator">+</span> item<span class="operator">-</span><span class="operator">></span>sizeHint()<span class="operator">.</span>width() <span class="operator">+</span> spaceX; <span class="keyword">if</span> (nextX <span class="operator">-</span> spaceX <span class="operator">></span> effectiveRect<span class="operator">.</span>right() <span class="operator">&</span><span class="operator">&</span> lineHeight <span class="operator">></span> <span class="number">0</span>) { x <span class="operator">=</span> effectiveRect<span class="operator">.</span>x(); y <span class="operator">=</span> y <span class="operator">+</span> lineHeight <span class="operator">+</span> spaceY; nextX <span class="operator">=</span> x <span class="operator">+</span> item<span class="operator">-</span><span class="operator">></span>sizeHint()<span class="operator">.</span>width() <span class="operator">+</span> spaceX; lineHeight <span class="operator">=</span> <span class="number">0</span>; } <span class="keyword">if</span> (<span class="operator">!</span>testOnly) item<span class="operator">-</span><span class="operator">></span>setGeometry(<span class="type"><a href="../qtcore/qrect.html">QRect</a></span>(<span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span>(x<span class="operator">,</span> y)<span class="operator">,</span> item<span class="operator">-</span><span class="operator">></span>sizeHint())); x <span class="operator">=</span> nextX; lineHeight <span class="operator">=</span> <a href="../qtcore/qtglobal.html#qMax">qMax</a>(lineHeight<span class="operator">,</span> item<span class="operator">-</span><span class="operator">></span>sizeHint()<span class="operator">.</span>height()); } <span class="keyword">return</span> y <span class="operator">+</span> lineHeight <span class="operator">-</span> rect<span class="operator">.</span>y() <span class="operator">+</span> bottom; } <span class="type">int</span> FlowLayout<span class="operator">::</span>smartSpacing(<span class="type"><a href="qstyle.html">QStyle</a></span><span class="operator">::</span>PixelMetric pm) <span class="keyword">const</span> { <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent <span class="operator">=</span> <span class="keyword">this</span><span class="operator">-</span><span class="operator">></span>parent(); <span class="keyword">if</span> (<span class="operator">!</span>parent) { <span class="keyword">return</span> <span class="operator">-</span><span class="number">1</span>; } <span class="keyword">else</span> <span class="keyword">if</span> (parent<span class="operator">-</span><span class="operator">></span>isWidgetType()) { <span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>pw <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span><span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span><span class="operator">></span>(parent); <span class="keyword">return</span> pw<span class="operator">-</span><span class="operator">></span>style()<span class="operator">-</span><span class="operator">></span>pixelMetric(pm<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> pw); } <span class="keyword">else</span> { <span class="keyword">return</span> <span class="keyword">static_cast</span><span class="operator"><</span><span class="type"><a href="qlayout.html">QLayout</a></span> <span class="operator">*</span><span class="operator">></span>(parent)<span class="operator">-</span><span class="operator">></span>spacing(); } } </pre> </div> <!-- @@@layouts/flowlayout/flowlayout.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>