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<h1 class="title">imagewidget.cpp Example File</h1>
<span class="small-subtitle">gestures/imagegestures/imagewidget.cpp</span>
<!-- $$$gestures/imagegestures/imagewidget.cpp-description -->
<div class="descr"> <a name="details"></a>
<pre class="cpp"> <span class="comment">/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** 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:
**
** &quot;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
** &quot;AS IS&quot; 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.&quot;
**
** $QT_END_LICENSE$
**
****************************************************************************/</span>
<span class="preprocessor">#include &quot;imagewidget.h&quot;</span>
<span class="preprocessor">#include &lt;QtGui&gt;</span>
<span class="type">bool</span> ImageWidget<span class="operator">::</span>verbose <span class="operator">=</span> <span class="keyword">false</span>;
ImageWidget<span class="operator">::</span>ImageWidget(<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="operator">,</span>
position(<span class="number">0</span>)<span class="operator">,</span>
horizontalOffset(<span class="number">0</span>)<span class="operator">,</span>
verticalOffset(<span class="number">0</span>)<span class="operator">,</span>
rotationAngle(<span class="number">0</span>)<span class="operator">,</span>
scaleFactor(<span class="number">1</span>)<span class="operator">,</span>
currentStepScaleFactor(<span class="number">1</span>)
{
setMinimumSize(<span class="type"><a href="qsize.html">QSize</a></span>(<span class="number">100</span><span class="operator">,</span><span class="number">100</span>));
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>grabGestures(<span class="keyword">const</span> <span class="type"><a href="qlist.html">QList</a></span><span class="operator">&lt;</span><span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>GestureType<span class="operator">&gt;</span> <span class="operator">&amp;</span>gestures)
{
foreach (<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>GestureType gesture<span class="operator">,</span> gestures)
grabGesture(gesture);
}
<span class="type">bool</span> ImageWidget<span class="operator">::</span>event(<span class="type"><a href="qevent.html">QEvent</a></span> <span class="operator">*</span>event)
{
<span class="keyword">if</span> (event<span class="operator">-</span><span class="operator">&gt;</span>type() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qevent.html">QEvent</a></span><span class="operator">::</span>Gesture)
<span class="keyword">return</span> gestureEvent(<span class="keyword">static_cast</span><span class="operator">&lt;</span><span class="type"><a href="qgestureevent.html">QGestureEvent</a></span><span class="operator">*</span><span class="operator">&gt;</span>(event));
<span class="keyword">return</span> <span class="type"><a href="qwidget.html">QWidget</a></span><span class="operator">::</span>event(event);
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>paintEvent(<span class="type"><a href="qpaintevent.html">QPaintEvent</a></span><span class="operator">*</span>)
{
<span class="type"><a href="qpainter.html">QPainter</a></span> p(<span class="keyword">this</span>);
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> iw <span class="operator">=</span> currentImage<span class="operator">.</span>width();
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> ih <span class="operator">=</span> currentImage<span class="operator">.</span>height();
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> wh <span class="operator">=</span> height();
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> ww <span class="operator">=</span> width();
p<span class="operator">.</span>translate(ww<span class="operator">/</span><span class="number">2</span><span class="operator">,</span> wh<span class="operator">/</span><span class="number">2</span>);
p<span class="operator">.</span>translate(horizontalOffset<span class="operator">,</span> verticalOffset);
p<span class="operator">.</span>rotate(rotationAngle);
p<span class="operator">.</span>scale(currentStepScaleFactor <span class="operator">*</span> scaleFactor<span class="operator">,</span> currentStepScaleFactor <span class="operator">*</span> scaleFactor);
p<span class="operator">.</span>translate(<span class="operator">-</span>iw<span class="operator">/</span><span class="number">2</span><span class="operator">,</span> <span class="operator">-</span>ih<span class="operator">/</span><span class="number">2</span>);
p<span class="operator">.</span>drawImage(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> currentImage);
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>mouseDoubleClickEvent(<span class="type"><a href="qmouseevent.html">QMouseEvent</a></span> <span class="operator">*</span>)
{
rotationAngle <span class="operator">=</span> <span class="number">0</span>;
scaleFactor <span class="operator">=</span> <span class="number">1</span>;
currentStepScaleFactor <span class="operator">=</span> <span class="number">1</span>;
verticalOffset <span class="operator">=</span> <span class="number">0</span>;
horizontalOffset <span class="operator">=</span> <span class="number">0</span>;
update();
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;reset on mouse double click&quot;</span>;
}
<span class="type">bool</span> ImageWidget<span class="operator">::</span>gestureEvent(<span class="type"><a href="qgestureevent.html">QGestureEvent</a></span> <span class="operator">*</span>event)
{
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;gestureEvent():&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> event<span class="operator">-</span><span class="operator">&gt;</span>gestures()<span class="operator">.</span>size();
<span class="keyword">if</span> (<span class="type"><a href="qgesture.html">QGesture</a></span> <span class="operator">*</span>swipe <span class="operator">=</span> event<span class="operator">-</span><span class="operator">&gt;</span>gesture(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>SwipeGesture))
swipeTriggered(<span class="keyword">static_cast</span><span class="operator">&lt;</span><span class="type"><a href="qswipegesture.html">QSwipeGesture</a></span> <span class="operator">*</span><span class="operator">&gt;</span>(swipe));
<span class="keyword">else</span> <span class="keyword">if</span> (<span class="type"><a href="qgesture.html">QGesture</a></span> <span class="operator">*</span>pan <span class="operator">=</span> event<span class="operator">-</span><span class="operator">&gt;</span>gesture(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>PanGesture))
panTriggered(<span class="keyword">static_cast</span><span class="operator">&lt;</span><span class="type"><a href="qpangesture.html">QPanGesture</a></span> <span class="operator">*</span><span class="operator">&gt;</span>(pan));
<span class="keyword">if</span> (<span class="type"><a href="qgesture.html">QGesture</a></span> <span class="operator">*</span>pinch <span class="operator">=</span> event<span class="operator">-</span><span class="operator">&gt;</span>gesture(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>PinchGesture))
pinchTriggered(<span class="keyword">static_cast</span><span class="operator">&lt;</span><span class="type"><a href="qpinchgesture.html">QPinchGesture</a></span> <span class="operator">*</span><span class="operator">&gt;</span>(pinch));
<span class="keyword">return</span> <span class="keyword">true</span>;
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>panTriggered(<span class="type"><a href="qpangesture.html">QPanGesture</a></span> <span class="operator">*</span>gesture)
{
<span class="preprocessor">#ifndef QT_NO_CURSOR</span>
<span class="keyword">switch</span> (gesture<span class="operator">-</span><span class="operator">&gt;</span>state()) {
<span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>GestureStarted:
<span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>GestureUpdated:
setCursor(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>SizeAllCursor);
<span class="keyword">break</span>;
<span class="keyword">default</span>:
setCursor(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>ArrowCursor);
}
<span class="preprocessor">#endif</span>
<span class="type"><a href="qpointf.html">QPointF</a></span> delta <span class="operator">=</span> gesture<span class="operator">-</span><span class="operator">&gt;</span>delta();
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;panTriggered():&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> delta;
horizontalOffset <span class="operator">+</span><span class="operator">=</span> delta<span class="operator">.</span>x();
verticalOffset <span class="operator">+</span><span class="operator">=</span> delta<span class="operator">.</span>y();
update();
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>pinchTriggered(<span class="type"><a href="qpinchgesture.html">QPinchGesture</a></span> <span class="operator">*</span>gesture)
{
<span class="type"><a href="qpinchgesture.html">QPinchGesture</a></span><span class="operator">::</span>ChangeFlags changeFlags <span class="operator">=</span> gesture<span class="operator">-</span><span class="operator">&gt;</span>changeFlags();
<span class="keyword">if</span> (changeFlags <span class="operator">&amp;</span> <span class="type"><a href="qpinchgesture.html">QPinchGesture</a></span><span class="operator">::</span>RotationAngleChanged) {
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> value <span class="operator">=</span> gesture<span class="operator">-</span><span class="operator">&gt;</span>property(<span class="string">&quot;rotationAngle&quot;</span>)<span class="operator">.</span>toReal();
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> lastValue <span class="operator">=</span> gesture<span class="operator">-</span><span class="operator">&gt;</span>property(<span class="string">&quot;lastRotationAngle&quot;</span>)<span class="operator">.</span>toReal();
<span class="keyword">const</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> rotationAngleDelta <span class="operator">=</span> value <span class="operator">-</span> lastValue;
rotationAngle <span class="operator">+</span><span class="operator">=</span> rotationAngleDelta;
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;pinchTriggered(): rotation by&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> rotationAngleDelta <span class="operator">&lt;</span><span class="operator">&lt;</span> rotationAngle;
}
<span class="keyword">if</span> (changeFlags <span class="operator">&amp;</span> <span class="type"><a href="qpinchgesture.html">QPinchGesture</a></span><span class="operator">::</span>ScaleFactorChanged) {
<span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> value <span class="operator">=</span> gesture<span class="operator">-</span><span class="operator">&gt;</span>property(<span class="string">&quot;scaleFactor&quot;</span>)<span class="operator">.</span>toReal();
currentStepScaleFactor <span class="operator">=</span> value;
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;pinchTriggered(): &quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> currentStepScaleFactor;
}
<span class="keyword">if</span> (gesture<span class="operator">-</span><span class="operator">&gt;</span>state() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>GestureFinished) {
scaleFactor <span class="operator">*</span><span class="operator">=</span> currentStepScaleFactor;
currentStepScaleFactor <span class="operator">=</span> <span class="number">1</span>;
}
update();
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>swipeTriggered(<span class="type"><a href="qswipegesture.html">QSwipeGesture</a></span> <span class="operator">*</span>gesture)
{
<span class="keyword">if</span> (gesture<span class="operator">-</span><span class="operator">&gt;</span>state() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>GestureFinished) {
<span class="keyword">if</span> (gesture<span class="operator">-</span><span class="operator">&gt;</span>horizontalDirection() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qswipegesture.html">QSwipeGesture</a></span><span class="operator">::</span>Left
<span class="operator">|</span><span class="operator">|</span> gesture<span class="operator">-</span><span class="operator">&gt;</span>verticalDirection() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qswipegesture.html">QSwipeGesture</a></span><span class="operator">::</span>Up) {
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;swipeTriggered(): swipe to previous&quot;</span>;
goPrevImage();
} <span class="keyword">else</span> {
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;swipeTriggered(): swipe to next&quot;</span>;
goNextImage();
}
update();
}
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>resizeEvent(<span class="type"><a href="qresizeevent.html">QResizeEvent</a></span><span class="operator">*</span>)
{
update();
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>openDirectory(<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&amp;</span>path)
{
<span class="keyword">this</span><span class="operator">-</span><span class="operator">&gt;</span>path <span class="operator">=</span> path;
<span class="type"><a href="qdir.html">QDir</a></span> dir(path);
<span class="type"><a href="qstringlist.html">QStringList</a></span> nameFilters;
nameFilters <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;*.jpg&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;*.png&quot;</span>;
files <span class="operator">=</span> dir<span class="operator">.</span>entryList(nameFilters<span class="operator">,</span> <span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>Files<span class="operator">|</span><span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>Readable<span class="operator">,</span> <span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>Name);
position <span class="operator">=</span> <span class="number">0</span>;
goToImage(<span class="number">0</span>);
update();
}
<span class="type"><a href="qimage.html">QImage</a></span> ImageWidget<span class="operator">::</span>loadImage(<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&amp;</span>fileName)
{
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> position <span class="operator">&lt;</span><span class="operator">&lt;</span> files <span class="operator">&lt;</span><span class="operator">&lt;</span> fileName;
<span class="type"><a href="qimagereader.html">QImageReader</a></span> reader(fileName);
<span class="keyword">if</span> (ImageWidget<span class="operator">::</span>verbose)
<a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;loading&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(fileName) <span class="operator">&lt;</span><span class="operator">&lt;</span> position <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="char">'/'</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> files<span class="operator">.</span>size();
<span class="keyword">if</span> (<span class="operator">!</span>reader<span class="operator">.</span>canRead()) {
<a href="qtglobal.html#qWarning">qWarning</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(fileName) <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;: can't load image&quot;</span>;
<span class="keyword">return</span> <span class="type"><a href="qimage.html">QImage</a></span>();
}
<span class="type"><a href="qimage.html">QImage</a></span> image;
<span class="keyword">if</span> (<span class="operator">!</span>reader<span class="operator">.</span>read(<span class="operator">&amp;</span>image)) {
<a href="qtglobal.html#qWarning">qWarning</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(fileName) <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;: corrupted image: &quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> reader<span class="operator">.</span>errorString();
<span class="keyword">return</span> <span class="type"><a href="qimage.html">QImage</a></span>();
}
<span class="keyword">const</span> <span class="type"><a href="qsize.html">QSize</a></span> maximumSize(<span class="number">2000</span><span class="operator">,</span> <span class="number">2000</span>); <span class="comment">// Reduce in case someone has large photo images.</span>
<span class="keyword">if</span> (image<span class="operator">.</span>size()<span class="operator">.</span>width() <span class="operator">&gt;</span> maximumSize<span class="operator">.</span>width() <span class="operator">|</span><span class="operator">|</span> image<span class="operator">.</span>height() <span class="operator">&gt;</span> maximumSize<span class="operator">.</span>height())
image <span class="operator">=</span> image<span class="operator">.</span>scaled(maximumSize<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>KeepAspectRatio<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>SmoothTransformation);
<span class="keyword">return</span> image;
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>goNextImage()
{
<span class="keyword">if</span> (files<span class="operator">.</span>isEmpty())
<span class="keyword">return</span>;
<span class="keyword">if</span> (position <span class="operator">&lt;</span> files<span class="operator">.</span>size()<span class="operator">-</span><span class="number">1</span>) {
<span class="operator">+</span><span class="operator">+</span>position;
prevImage <span class="operator">=</span> currentImage;
currentImage <span class="operator">=</span> nextImage;
<span class="keyword">if</span> (position<span class="operator">+</span><span class="number">1</span> <span class="operator">&lt;</span> files<span class="operator">.</span>size())
nextImage <span class="operator">=</span> loadImage(path<span class="operator">+</span>QLatin1String(<span class="string">&quot;/&quot;</span>)<span class="operator">+</span>files<span class="operator">.</span>at(position<span class="operator">+</span><span class="number">1</span>));
<span class="keyword">else</span>
nextImage <span class="operator">=</span> <span class="type"><a href="qimage.html">QImage</a></span>();
}
update();
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>goPrevImage()
{
<span class="keyword">if</span> (files<span class="operator">.</span>isEmpty())
<span class="keyword">return</span>;
<span class="keyword">if</span> (position <span class="operator">&gt;</span> <span class="number">0</span>) {
<span class="operator">-</span><span class="operator">-</span>position;
nextImage <span class="operator">=</span> currentImage;
currentImage <span class="operator">=</span> prevImage;
<span class="keyword">if</span> (position <span class="operator">&gt;</span> <span class="number">0</span>)
prevImage <span class="operator">=</span> loadImage(path<span class="operator">+</span>QLatin1String(<span class="string">&quot;/&quot;</span>)<span class="operator">+</span>files<span class="operator">.</span>at(position<span class="operator">-</span><span class="number">1</span>));
<span class="keyword">else</span>
prevImage <span class="operator">=</span> <span class="type"><a href="qimage.html">QImage</a></span>();
}
update();
}
<span class="type">void</span> ImageWidget<span class="operator">::</span>goToImage(<span class="type">int</span> index)
{
<span class="keyword">if</span> (files<span class="operator">.</span>isEmpty())
<span class="keyword">return</span>;
<span class="keyword">if</span> (index <span class="operator">&lt;</span> <span class="number">0</span> <span class="operator">|</span><span class="operator">|</span> index <span class="operator">&gt;</span><span class="operator">=</span> files<span class="operator">.</span>size()) {
<a href="qtglobal.html#qWarning">qWarning</a>() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;goToImage: invalid index: &quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> index;
<span class="keyword">return</span>;
}
<span class="keyword">if</span> (index <span class="operator">=</span><span class="operator">=</span> position<span class="operator">+</span><span class="number">1</span>) {
goNextImage();
<span class="keyword">return</span>;
}
<span class="keyword">if</span> (position <span class="operator">&gt;</span> <span class="number">0</span> <span class="operator">&amp;</span><span class="operator">&amp;</span> index <span class="operator">=</span><span class="operator">=</span> position<span class="operator">-</span><span class="number">1</span>) {
goPrevImage();
<span class="keyword">return</span>;
}
position <span class="operator">=</span> index;
<span class="keyword">if</span> (index <span class="operator">&gt;</span> <span class="number">0</span>)
prevImage <span class="operator">=</span> loadImage(path<span class="operator">+</span>QLatin1String(<span class="string">&quot;/&quot;</span>)<span class="operator">+</span>files<span class="operator">.</span>at(position<span class="operator">-</span><span class="number">1</span>));
<span class="keyword">else</span>
prevImage <span class="operator">=</span> <span class="type"><a href="qimage.html">QImage</a></span>();
currentImage <span class="operator">=</span> loadImage(path<span class="operator">+</span>QLatin1String(<span class="string">&quot;/&quot;</span>)<span class="operator">+</span>files<span class="operator">.</span>at(position));
<span class="keyword">if</span> (position<span class="operator">+</span><span class="number">1</span> <span class="operator">&lt;</span> files<span class="operator">.</span>size())
nextImage <span class="operator">=</span> loadImage(path<span class="operator">+</span>QLatin1String(<span class="string">&quot;/&quot;</span>)<span class="operator">+</span>files<span class="operator">.</span>at(position<span class="operator">+</span><span class="number">1</span>));
<span class="keyword">else</span>
nextImage <span class="operator">=</span> <span class="type"><a href="qimage.html">QImage</a></span>();
update();
}</pre>
</div>
<!-- @@@gestures/imagegestures/imagewidget.cpp -->
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