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Breadcrumbs go here --> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <h1 class="title">dragwidget.cpp Example File</h1> <span class="small-subtitle">draganddrop/fridgemagnets/dragwidget.cpp</span> <!-- $$$draganddrop/fridgemagnets/dragwidget.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** 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 Digia Plc and its Subsidiary(-ies) 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 <QtGui></span> <span class="preprocessor">#include "draglabel.h"</span> <span class="preprocessor">#include "dragwidget.h"</span> DragWidget<span class="operator">::</span>DragWidget(<span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qwidget.html">QWidget</a></span>(parent) { <span class="type"><a href="qfile.html">QFile</a></span> dictionaryFile(<span class="string">":/dictionary/words.txt"</span>); dictionaryFile<span class="operator">.</span>open(<span class="type"><a href="qfile.html">QFile</a></span><span class="operator">::</span>ReadOnly); <span class="type"><a href="qtextstream.html">QTextStream</a></span> inputStream(<span class="operator">&</span>dictionaryFile); <span class="type">int</span> x <span class="operator">=</span> <span class="number">5</span>; <span class="type">int</span> y <span class="operator">=</span> <span class="number">5</span>; <span class="keyword">while</span> (<span class="operator">!</span>inputStream<span class="operator">.</span>atEnd()) { <span class="type"><a href="qstring.html">QString</a></span> word; word <span class="operator">=</span> inputStream<span class="operator">.</span>readLine(); <span class="keyword">if</span> (<span class="operator">!</span>word<span class="operator">.</span>isEmpty()) { DragLabel <span class="operator">*</span>wordLabel <span class="operator">=</span> <span class="keyword">new</span> DragLabel(word<span class="operator">,</span> <span class="keyword">this</span>); wordLabel<span class="operator">-</span><span class="operator">></span>move(x<span class="operator">,</span> y); wordLabel<span class="operator">-</span><span class="operator">></span>show(); wordLabel<span class="operator">-</span><span class="operator">></span>setAttribute(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>WA_DeleteOnClose); x <span class="operator">+</span><span class="operator">=</span> wordLabel<span class="operator">-</span><span class="operator">></span>width() <span class="operator">+</span> <span class="number">2</span>; <span class="preprocessor">#if defined(Q_WS_MAEMO_5) || defined(Q_WS_SIMULATOR)</span> <span class="keyword">if</span> (x <span class="operator">></span><span class="operator">=</span> <span class="number">345</span>) { <span class="preprocessor">#else</span> <span class="keyword">if</span> (x <span class="operator">></span><span class="operator">=</span> <span class="number">245</span>) { <span class="preprocessor">#endif</span> x <span class="operator">=</span> <span class="number">5</span>; y <span class="operator">+</span><span class="operator">=</span> wordLabel<span class="operator">-</span><span class="operator">></span>height() <span class="operator">+</span> <span class="number">2</span>; } } } <span class="preprocessor">#ifndef Q_WS_S60</span> <span class="comment">//Fridge magnets is used for demoing Qt on S60 and themed backgrounds look better than white</span> <span class="type"><a href="qpalette.html">QPalette</a></span> newPalette <span class="operator">=</span> palette(); newPalette<span class="operator">.</span>setColor(<span class="type"><a href="qpalette.html">QPalette</a></span><span class="operator">::</span>Window<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>white); setPalette(newPalette); <span class="preprocessor">#endif</span> setMinimumSize(<span class="number">400</span><span class="operator">,</span> <a href="qtglobal.html#qMax">qMax</a>(<span class="number">200</span><span class="operator">,</span> y)); setWindowTitle(tr(<span class="string">"Fridge Magnets"</span>)); setAcceptDrops(<span class="keyword">true</span>); } <span class="type">void</span> DragWidget<span class="operator">::</span>dragEnterEvent(<span class="type"><a href="qdragenterevent.html">QDragEnterEvent</a></span> <span class="operator">*</span>event) { <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>hasFormat(<span class="string">"application/x-fridgemagnet"</span>)) { <span class="keyword">if</span> (children()<span class="operator">.</span>contains(event<span class="operator">-</span><span class="operator">></span>source())) { event<span class="operator">-</span><span class="operator">></span>setDropAction(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>MoveAction); event<span class="operator">-</span><span class="operator">></span>accept(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>acceptProposedAction(); } } <span class="keyword">else</span> <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>hasText()) { event<span class="operator">-</span><span class="operator">></span>acceptProposedAction(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>ignore(); } } <span class="type">void</span> DragWidget<span class="operator">::</span>dragMoveEvent(<span class="type"><a href="qdragmoveevent.html">QDragMoveEvent</a></span> <span class="operator">*</span>event) { <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>hasFormat(<span class="string">"application/x-fridgemagnet"</span>)) { <span class="keyword">if</span> (children()<span class="operator">.</span>contains(event<span class="operator">-</span><span class="operator">></span>source())) { event<span class="operator">-</span><span class="operator">></span>setDropAction(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>MoveAction); event<span class="operator">-</span><span class="operator">></span>accept(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>acceptProposedAction(); } } <span class="keyword">else</span> <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>hasText()) { event<span class="operator">-</span><span class="operator">></span>acceptProposedAction(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>ignore(); } } <span class="type">void</span> DragWidget<span class="operator">::</span>dropEvent(<span class="type"><a href="qdropevent.html">QDropEvent</a></span> <span class="operator">*</span>event) { <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>hasFormat(<span class="string">"application/x-fridgemagnet"</span>)) { <span class="keyword">const</span> <span class="type"><a href="qmimedata.html">QMimeData</a></span> <span class="operator">*</span>mime <span class="operator">=</span> event<span class="operator">-</span><span class="operator">></span>mimeData(); <span class="type"><a href="qbytearray.html">QByteArray</a></span> itemData <span class="operator">=</span> mime<span class="operator">-</span><span class="operator">></span>data(<span class="string">"application/x-fridgemagnet"</span>); <span class="type"><a href="qdatastream.html">QDataStream</a></span> dataStream(<span class="operator">&</span>itemData<span class="operator">,</span> <span class="type"><a href="qiodevice.html">QIODevice</a></span><span class="operator">::</span>ReadOnly); <span class="type"><a href="qstring.html">QString</a></span> text; <span class="type"><a href="qpoint.html">QPoint</a></span> offset; dataStream <span class="operator">></span><span class="operator">></span> text <span class="operator">></span><span class="operator">></span> offset; DragLabel <span class="operator">*</span>newLabel <span class="operator">=</span> <span class="keyword">new</span> DragLabel(text<span class="operator">,</span> <span class="keyword">this</span>); newLabel<span class="operator">-</span><span class="operator">></span>move(event<span class="operator">-</span><span class="operator">></span>pos() <span class="operator">-</span> offset); newLabel<span class="operator">-</span><span class="operator">></span>show(); newLabel<span class="operator">-</span><span class="operator">></span>setAttribute(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>WA_DeleteOnClose); <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>source() <span class="operator">=</span><span class="operator">=</span> <span class="keyword">this</span>) { event<span class="operator">-</span><span class="operator">></span>setDropAction(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>MoveAction); event<span class="operator">-</span><span class="operator">></span>accept(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>acceptProposedAction(); } } <span class="keyword">else</span> <span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>hasText()) { <span class="type"><a href="qstringlist.html">QStringList</a></span> pieces <span class="operator">=</span> event<span class="operator">-</span><span class="operator">></span>mimeData()<span class="operator">-</span><span class="operator">></span>text()<span class="operator">.</span>split(<span class="type"><a href="qregexp.html">QRegExp</a></span>(<span class="string">"\\s+"</span>)<span class="operator">,</span> <span class="type"><a href="qstring.html">QString</a></span><span class="operator">::</span>SkipEmptyParts); <span class="type"><a href="qpoint.html">QPoint</a></span> position <span class="operator">=</span> event<span class="operator">-</span><span class="operator">></span>pos(); foreach (<span class="type"><a href="qstring.html">QString</a></span> piece<span class="operator">,</span> pieces) { DragLabel <span class="operator">*</span>newLabel <span class="operator">=</span> <span class="keyword">new</span> DragLabel(piece<span class="operator">,</span> <span class="keyword">this</span>); newLabel<span class="operator">-</span><span class="operator">></span>move(position); newLabel<span class="operator">-</span><span class="operator">></span>show(); newLabel<span class="operator">-</span><span class="operator">></span>setAttribute(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>WA_DeleteOnClose); position <span class="operator">+</span><span class="operator">=</span> <span class="type"><a href="qpoint.html">QPoint</a></span>(newLabel<span class="operator">-</span><span class="operator">></span>width()<span class="operator">,</span> <span class="number">0</span>); } event<span class="operator">-</span><span class="operator">></span>acceptProposedAction(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>ignore(); } } <span class="type">void</span> DragWidget<span class="operator">::</span>mousePressEvent(<span class="type"><a href="qmouseevent.html">QMouseEvent</a></span> <span class="operator">*</span>event) { DragLabel <span class="operator">*</span>child <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span>DragLabel<span class="operator">*</span><span class="operator">></span>(childAt(event<span class="operator">-</span><span class="operator">></span>pos())); <span class="keyword">if</span> (<span class="operator">!</span>child) <span class="keyword">return</span>; <span class="type"><a href="qpoint.html">QPoint</a></span> hotSpot <span class="operator">=</span> event<span class="operator">-</span><span class="operator">></span>pos() <span class="operator">-</span> child<span class="operator">-</span><span class="operator">></span>pos(); <span class="type"><a href="qbytearray.html">QByteArray</a></span> itemData; <span class="type"><a href="qdatastream.html">QDataStream</a></span> dataStream(<span class="operator">&</span>itemData<span class="operator">,</span> <span class="type"><a href="qiodevice.html">QIODevice</a></span><span class="operator">::</span>WriteOnly); dataStream <span class="operator"><</span><span class="operator"><</span> child<span class="operator">-</span><span class="operator">></span>labelText() <span class="operator"><</span><span class="operator"><</span> <span class="type"><a href="qpoint.html">QPoint</a></span>(hotSpot); <span class="type"><a href="qmimedata.html">QMimeData</a></span> <span class="operator">*</span>mimeData <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qmimedata.html">QMimeData</a></span>; mimeData<span class="operator">-</span><span class="operator">></span>setData(<span class="string">"application/x-fridgemagnet"</span><span class="operator">,</span> itemData); mimeData<span class="operator">-</span><span class="operator">></span>setText(child<span class="operator">-</span><span class="operator">></span>labelText()); <span class="type"><a href="qdrag.html">QDrag</a></span> <span class="operator">*</span>drag <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qdrag.html">QDrag</a></span>(<span class="keyword">this</span>); drag<span class="operator">-</span><span class="operator">></span>setMimeData(mimeData); drag<span class="operator">-</span><span class="operator">></span>setPixmap(<span class="operator">*</span>child<span class="operator">-</span><span class="operator">></span>pixmap()); drag<span class="operator">-</span><span class="operator">></span>setHotSpot(hotSpot); child<span class="operator">-</span><span class="operator">></span>hide(); <span class="keyword">if</span> (drag<span class="operator">-</span><span class="operator">></span>exec(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>MoveAction <span class="operator">|</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>CopyAction<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>CopyAction) <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>MoveAction) child<span class="operator">-</span><span class="operator">></span>close(); <span class="keyword">else</span> child<span class="operator">-</span><span class="operator">></span>show(); }</pre> </div> <!-- @@@draganddrop/fridgemagnets/dragwidget.cpp --> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2013 Digia Plc and/or its subsidiaries. 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