<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en_US" lang="en_US">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!-- elidedlabel.qdoc -->
<title>Qt 4.8: Elided Label Example</title>
<link rel="stylesheet" type="text/css" href="style/style.css" />
<script src="scripts/jquery.js" type="text/javascript"></script>
<script src="scripts/functions.js" type="text/javascript"></script>
<link rel="stylesheet" type="text/css" href="style/superfish.css" />
<link rel="stylesheet" type="text/css" href="style/narrow.css" />
<!--[if IE]>
<meta name="MSSmartTagsPreventParsing" content="true">
<meta http-equiv="imagetoolbar" content="no">
<![endif]-->
<!--[if lt IE 7]>
<link rel="stylesheet" type="text/css" href="style/style_ie6.css">
<![endif]-->
<!--[if IE 7]>
<link rel="stylesheet" type="text/css" href="style/style_ie7.css">
<![endif]-->
<!--[if IE 8]>
<link rel="stylesheet" type="text/css" href="style/style_ie8.css">
<![endif]-->
<script src="scripts/superfish.js" type="text/javascript"></script>
<script src="scripts/narrow.js" type="text/javascript"></script>
</head>
<body class="" onload="CheckEmptyAndLoadList();">
<div class="header" id="qtdocheader">
<div class="content">
<div id="nav-logo">
<a href="index.html">Home</a></div>
<a href="index.html" class="qtref"><span>Qt Reference Documentation</span></a>
<div id="narrowsearch"></div>
<div id="nav-topright">
<ul>
<li class="nav-topright-home"><a href="http://qt.digia.com/">Qt HOME</a></li>
<li class="nav-topright-dev"><a href="http://qt-project.org/">DEV</a></li>
<li class="nav-topright-doc nav-topright-doc-active"><a href="http://qt-project.org/doc/">
DOC</a></li>
<li class="nav-topright-blog"><a href="http://blog.qt.digia.com/">BLOG</a></li>
</ul>
</div>
<div id="shortCut">
<ul>
<li class="shortCut-topleft-inactive"><span><a href="index.html">Qt 4.8</a></span></li>
<li class="shortCut-topleft-active"><a href="http://qt-project.org/doc/">ALL VERSIONS </a></li>
</ul>
</div>
<ul class="sf-menu" id="narrowmenu">
<li><a href="#">API Lookup</a>
<ul>
<li><a href="classes.html">Class index</a></li>
<li><a href="functions.html">Function index</a></li>
<li><a href="modules.html">Modules</a></li>
<li><a href="namespaces.html">Namespaces</a></li>
<li><a href="qtglobal.html">Global Declarations</a></li>
<li><a href="qdeclarativeelements.html">QML elements</a></li>
</ul>
</li>
<li><a href="#">Qt Topics</a>
<ul>
<li><a href="qt-basic-concepts.html">Programming with Qt</a></li>
<li><a href="qtquick.html">Device UIs & Qt Quick</a></li>
<li><a href="qt-gui-concepts.html">UI Design with Qt</a></li>
<li><a href="supported-platforms.html">Supported Platforms</a></li>
<li><a href="technology-apis.html">Qt and Key Technologies</a></li>
<li><a href="best-practices.html">How-To's and Best Practices</a></li>
</ul>
</li>
<li><a href="#">Examples</a>
<ul>
<li><a href="all-examples.html">Examples</a></li>
<li><a href="tutorials.html">Tutorials</a></li>
<li><a href="demos.html">Demos</a></li>
<li><a href="qdeclarativeexamples.html">QML Examples</a></li>
</ul>
</li>
</ul>
</div>
</div>
<div class="wrapper">
<div class="hd">
<span></span>
</div>
<div class="bd group">
<div class="sidebar">
<div class="searchlabel">
Search index:</div>
<div class="search" id="sidebarsearch">
<form id="qtdocsearch" action="" onsubmit="return false;">
<fieldset>
<input type="text" name="searchstring" id="pageType" value="" />
<div id="resultdialog">
<a href="#" id="resultclose">Close</a>
<p id="resultlinks" class="all"><a href="#" id="showallresults">All</a> | <a href="#" id="showapiresults">API</a> | <a href="#" id="showarticleresults">Articles</a> | <a href="#" id="showexampleresults">Examples</a></p>
<p id="searchcount" class="all"><span id="resultcount"></span><span id="apicount"></span><span id="articlecount"></span><span id="examplecount"></span> results:</p>
<ul id="resultlist" class="all">
</ul>
</div>
</fieldset>
</form>
</div>
<div class="box first bottombar" id="lookup">
<h2 title="API Lookup"><span></span>
API Lookup</h2>
<div id="list001" class="list">
<ul id="ul001" >
<li class="defaultLink"><a href="classes.html">Class index</a></li>
<li class="defaultLink"><a href="functions.html">Function index</a></li>
<li class="defaultLink"><a href="modules.html">Modules</a></li>
<li class="defaultLink"><a href="namespaces.html">Namespaces</a></li>
<li class="defaultLink"><a href="qtglobal.html">Global Declarations</a></li>
<li class="defaultLink"><a href="qdeclarativeelements.html">QML elements</a></li>
</ul>
</div>
</div>
<div class="box bottombar" id="topics">
<h2 title="Qt Topics"><span></span>
Qt Topics</h2>
<div id="list002" class="list">
<ul id="ul002" >
<li class="defaultLink"><a href="qt-basic-concepts.html">Programming with Qt</a></li>
<li class="defaultLink"><a href="qtquick.html">Device UIs & Qt Quick</a></li>
<li class="defaultLink"><a href="qt-gui-concepts.html">UI Design with Qt</a></li>
<li class="defaultLink"><a href="supported-platforms.html">Supported Platforms</a></li>
<li class="defaultLink"><a href="technology-apis.html">Qt and Key Technologies</a></li>
<li class="defaultLink"><a href="best-practices.html">How-To's and Best Practices</a></li>
</ul>
</div>
</div>
<div class="box" id="examples">
<h2 title="Examples"><span></span>
Examples</h2>
<div id="list003" class="list">
<ul id="ul003">
<li class="defaultLink"><a href="all-examples.html">Examples</a></li>
<li class="defaultLink"><a href="tutorials.html">Tutorials</a></li>
<li class="defaultLink"><a href="demos.html">Demos</a></li>
<li class="defaultLink"><a href="qdeclarativeexamples.html">QML Examples</a></li>
</ul>
</div>
</div>
</div>
<div class="wrap">
<div class="toolbar">
<div class="breadcrumb toolblock">
<ul>
<li class="first"><a href="index.html">Home</a></li>
<!-- Breadcrumbs go here -->
<li><a href="all-examples.html">Examples</a></li>
<li>Elided Label Example</li>
</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">
<div class="toc">
<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#elidedlabel-class-definition">ElidedLabel Class Definition</a></li>
<li class="level1"><a href="#elidedlabel-class-implementation">ElidedLabel Class Implementation</a></li>
<li class="level1"><a href="#testwidget-class-definition">TestWidget Class Definition</a></li>
<li class="level1"><a href="#testwidget-class-implementation">TestWidget Class Implementation</a></li>
<li class="level1"><a href="#the-function">The <tt>main()</tt> Function</a></li>
</ul>
</div>
<h1 class="title">Elided Label Example</h1>
<span class="subtitle"></span>
<!-- $$$widgets/elidedlabel-description -->
<div class="descr"> <a name="details"></a>
<p>Files:</p>
<ul>
<li><a href="widgets-elidedlabel-elidedlabel-cpp.html">widgets/elidedlabel/elidedlabel.cpp</a></li>
<li><a href="widgets-elidedlabel-elidedlabel-h.html">widgets/elidedlabel/elidedlabel.h</a></li>
<li><a href="widgets-elidedlabel-testwidget-cpp.html">widgets/elidedlabel/testwidget.cpp</a></li>
<li><a href="widgets-elidedlabel-testwidget-h.html">widgets/elidedlabel/testwidget.h</a></li>
<li><a href="widgets-elidedlabel-main-cpp.html">widgets/elidedlabel/main.cpp</a></li>
<li><a href="widgets-elidedlabel-elidedlabel-pro.html">widgets/elidedlabel/elidedlabel.pro</a></li>
</ul>
<p>The Elided Label example creates a widget similar to <a href="qlabel.html">QLabel</a>, that elides the last visible line, if the text is too long to fit the widget's geometry.<p class="centerAlign"><img src="images/elidedlabel-example.png" alt="Elided Label example on XPressMusic 5800" /></p><p>When text of varying length has to be displayed in a uniformly sized area, for instance within a list or grid view where all list items have the same size, it can be useful to give the user a visual clue when not all text is visible. <a href="qlabel.html">QLabel</a> can elide text that doesn't fit within it, but only in one line. The <tt>ElidedLabel</tt> widget shown in this example word wraps its text by its width, and elides the last visible line if some text is left out. <tt>TestWidget</tt> gives control to the features of <tt>ElidedWidget</tt> and forms the example application.</p>
<a name="elidedlabel-class-definition"></a>
<h2>ElidedLabel Class Definition</h2>
<p>Like <a href="qlabel.html">QLabel</a>, <tt>ElidedLabel</tt> inherits from <a href="qframe.html">QFrame</a>. Here's the definition of the <tt>ElidedLabel</tt> class:</p>
<pre class="cpp"> <span class="keyword">class</span> ElidedLabel : <span class="keyword">public</span> <span class="type"><a href="qframe.html">QFrame</a></span>
{
Q_OBJECT
Q_PROPERTY(<span class="type"><a href="qstring.html">QString</a></span> text READ text WRITE setText)
Q_PROPERTY(<span class="type">bool</span> isElided READ isElided)
<span class="keyword">public</span>:
ElidedLabel(<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&</span>text<span class="operator">,</span> <span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent <span class="operator">=</span> <span class="number">0</span>);
<span class="type">void</span> setText(<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&</span>text);
<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&</span> text() <span class="keyword">const</span> { <span class="keyword">return</span> content; }
<span class="type">bool</span> isElided() <span class="keyword">const</span> { <span class="keyword">return</span> elided; }
<span class="keyword">protected</span>:
<span class="type">void</span> paintEvent(<span class="type"><a href="qpaintevent.html">QPaintEvent</a></span> <span class="operator">*</span>event);
<span class="keyword">signals</span>:
<span class="type">void</span> elisionChanged(<span class="type">bool</span> elided);
<span class="keyword">private</span>:
<span class="type">bool</span> elided;
<span class="type"><a href="qstring.html">QString</a></span> content;
};</pre>
<p>The <tt>isElided</tt> property depends the font, text content and geometry of the widget. Whenever any of these change, the <tt>elisionChanged()</tt> signal might trigger. We cache the current elision value in <tt>elided</tt>, so that it doesn't have to be recomputed every time it's asked for.</p>
<a name="elidedlabel-class-implementation"></a>
<h2>ElidedLabel Class Implementation</h2>
<p>Except for initializing the member variables, the constructor sets the size policy to be horizontally expanding, since it's meant to fill the width of its container and grow vertically.</p>
<pre class="cpp"> ElidedLabel<span class="operator">::</span>ElidedLabel(<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&</span>text<span class="operator">,</span> <span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent)
: <span class="type"><a href="qframe.html">QFrame</a></span>(parent)
<span class="operator">,</span> elided(<span class="keyword">false</span>)
<span class="operator">,</span> content(text)
{
setSizePolicy(<span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>Expanding<span class="operator">,</span> <span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>Preferred);
}</pre>
<p>Changing the <tt>content</tt> require a repaint of the widget.</p>
<pre class="cpp"> <span class="type">void</span> ElidedLabel<span class="operator">::</span>setText(<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> <span class="operator">&</span>newText)
{
content <span class="operator">=</span> newText;
update();
}</pre>
<p><a href="qtextlayout.html">QTextLayout</a> is used in the <tt>paintEvent()</tt> to divide the <tt>content</tt> into lines, that wrap on word boundaries. Each line, except the last visible one, is drawn <tt>lineSpacing</tt> pixels below the previous one. The <tt>draw()</tt> method of <a href="qtextline.html">QTextLine</a> will draw the line using the coordinate point as the top left corner.</p>
<pre class="cpp"> <span class="type">void</span> ElidedLabel<span class="operator">::</span>paintEvent(<span class="type"><a href="qpaintevent.html">QPaintEvent</a></span> <span class="operator">*</span>event)
{
<span class="type"><a href="qframe.html">QFrame</a></span><span class="operator">::</span>paintEvent(event);
<span class="type"><a href="qpainter.html">QPainter</a></span> painter(<span class="keyword">this</span>);
<span class="type"><a href="qfontmetrics.html">QFontMetrics</a></span> fontMetrics <span class="operator">=</span> painter<span class="operator">.</span>fontMetrics();
<span class="type">bool</span> didElide <span class="operator">=</span> <span class="keyword">false</span>;
<span class="type">int</span> lineSpacing <span class="operator">=</span> fontMetrics<span class="operator">.</span>lineSpacing();
<span class="type">int</span> y <span class="operator">=</span> <span class="number">0</span>;
<span class="type"><a href="qtextlayout.html">QTextLayout</a></span> textLayout(content<span class="operator">,</span> painter<span class="operator">.</span>font());
textLayout<span class="operator">.</span>beginLayout();
forever {
<span class="type"><a href="qtextline.html">QTextLine</a></span> line <span class="operator">=</span> textLayout<span class="operator">.</span>createLine();
<span class="keyword">if</span> (<span class="operator">!</span>line<span class="operator">.</span>isValid())
<span class="keyword">break</span>;
line<span class="operator">.</span>setLineWidth(width());
<span class="type">int</span> nextLineY <span class="operator">=</span> y <span class="operator">+</span> lineSpacing;
<span class="keyword">if</span> (height() <span class="operator">></span><span class="operator">=</span> nextLineY <span class="operator">+</span> lineSpacing) {
line<span class="operator">.</span>draw(<span class="operator">&</span>painter<span class="operator">,</span> <span class="type"><a href="qpoint.html">QPoint</a></span>(<span class="number">0</span><span class="operator">,</span> y));
y <span class="operator">=</span> nextLineY;</pre>
<p>Unfortunately, <a href="qtextlayout.html">QTextLayout</a> does not elide text, so the last visible line has to be treated differently. This last line is elided if it is too wide. The <tt>drawText()</tt> method of <a href="qpainter.html">QPainter</a> draws the text starting from the base line, which is <tt>ascecnt()</tt> pixels below the last drawn line.</p>
<p>Finally, one more line is created to see if everything fit on this line.</p>
<pre class="cpp"> } <span class="keyword">else</span> {
<span class="type"><a href="qstring.html">QString</a></span> lastLine <span class="operator">=</span> content<span class="operator">.</span>mid(line<span class="operator">.</span>textStart());
<span class="type"><a href="qstring.html">QString</a></span> elidedLastLine <span class="operator">=</span> fontMetrics<span class="operator">.</span>elidedText(lastLine<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>ElideRight<span class="operator">,</span> width());
painter<span class="operator">.</span>drawText(<span class="type"><a href="qpoint.html">QPoint</a></span>(<span class="number">0</span><span class="operator">,</span> y <span class="operator">+</span> fontMetrics<span class="operator">.</span>ascent())<span class="operator">,</span> elidedLastLine);
line <span class="operator">=</span> textLayout<span class="operator">.</span>createLine();
didElide <span class="operator">=</span> line<span class="operator">.</span>isValid();
<span class="keyword">break</span>;
}
}
textLayout<span class="operator">.</span>endLayout();</pre>
<p>If the text was elided and wasn't before or vice versa, cache it in <tt>elided</tt> and emit the change.</p>
<pre class="cpp"> <span class="keyword">if</span> (didElide <span class="operator">!</span><span class="operator">=</span> elided) {
elided <span class="operator">=</span> didElide;
<span class="keyword">emit</span> elisionChanged(didElide);
}
}</pre>
<a name="testwidget-class-definition"></a>
<h2>TestWidget Class Definition</h2>
<p><tt>TestWidget</tt> is a <a href="qwidget.html">QWidget</a> and is the main window of the example. It contains an <tt>ElidedLabel</tt> which can be resized with two <a href="qslider.html">QSlider</a> widgets.</p>
<pre class="cpp"> <span class="keyword">class</span> TestWidget : <span class="keyword">public</span> <span class="type"><a href="qwidget.html">QWidget</a></span>
{
Q_OBJECT
<span class="keyword">public</span>:
TestWidget(<span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent <span class="operator">=</span> <span class="number">0</span>);
<span class="keyword">protected</span>:
<span class="type">void</span> resizeEvent(<span class="type"><a href="qresizeevent.html">QResizeEvent</a></span> <span class="operator">*</span>event);
<span class="keyword">private</span> <span class="keyword">slots</span>:
<span class="type">void</span> switchText();
<span class="type">void</span> onWidthChanged(<span class="type">int</span> width);
<span class="type">void</span> onHeightChanged(<span class="type">int</span> height);
<span class="keyword">private</span>:
<span class="type">int</span> sampleIndex;
<span class="type"><a href="qstringlist.html">QStringList</a></span> textSamples;
ElidedLabel <span class="operator">*</span>elidedText;
<span class="type"><a href="qslider.html">QSlider</a></span> <span class="operator">*</span>heightSlider;
<span class="type"><a href="qslider.html">QSlider</a></span> <span class="operator">*</span>widthSlider;
};</pre>
<a name="testwidget-class-implementation"></a>
<h2>TestWidget Class Implementation</h2>
<p>The constructor initializes the whole widget. Strings of different length are stored in <tt>textSamples</tt>. The user is able to switch between these.</p>
<pre class="cpp"> TestWidget<span class="operator">::</span>TestWidget(<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="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> romeo <span class="operator">=</span> tr(
<span class="string">"But soft, what light through yonder window breaks? / "</span>
<span class="string">"It is the east, and Juliet is the sun. / "</span>
<span class="string">"Arise, fair sun, and kill the envious moon, / "</span>
<span class="string">"Who is already sick and pale with grief / "</span>
<span class="string">"That thou, her maid, art far more fair than she."</span>
);
<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> macbeth <span class="operator">=</span> tr(
<span class="string">"To-morrow, and to-morrow, and to-morrow, / "</span>
<span class="string">"Creeps in this petty pace from day to day, / "</span>
<span class="string">"To the last syllable of recorded time; / "</span>
<span class="string">"And all our yesterdays have lighted fools / "</span>
<span class="string">"The way to dusty death. Out, out, brief candle! / "</span>
<span class="string">"Life's but a walking shadow, a poor player, / "</span>
<span class="string">"That struts and frets his hour upon the stage, / "</span>
<span class="string">"And then is heard no more. It is a tale / "</span>
<span class="string">"Told by an idiot, full of sound and fury, / "</span>
<span class="string">"Signifying nothing."</span>
);
<span class="keyword">const</span> <span class="type"><a href="qstring.html">QString</a></span> harry <span class="operator">=</span> tr(<span class="string">"Feeling lucky, punk?"</span>);
textSamples <span class="operator"><</span><span class="operator"><</span> romeo <span class="operator"><</span><span class="operator"><</span> macbeth <span class="operator"><</span><span class="operator"><</span> harry;</pre>
<p>An <tt>ElidedLabel</tt> is created to contain the first of the sample strings. The frame is made visible to make it easier to see the actual size of the widget.</p>
<pre class="cpp"> sampleIndex <span class="operator">=</span> <span class="number">0</span>;
elidedText <span class="operator">=</span> <span class="keyword">new</span> ElidedLabel(textSamples<span class="operator">[</span>sampleIndex<span class="operator">]</span><span class="operator">,</span> <span class="keyword">this</span>);
elidedText<span class="operator">-</span><span class="operator">></span>setFrameStyle(<span class="type"><a href="qframe.html">QFrame</a></span><span class="operator">::</span>Box);</pre>
<p>The buttons and the elision label are created. By connecting the <tt>elisionChanged()</tt> signal to the <tt>setVisible()</tt> slot of the <tt>label</tt>, it will act as an indicator to when the text is elided or not. This signal could, for instance, be used to make a "More" button visible, or similar.</p>
<pre class="cpp"> <span class="type"><a href="qpushbutton.html">QPushButton</a></span> <span class="operator">*</span>switchButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qpushbutton.html">QPushButton</a></span>(tr(<span class="string">"Switch text"</span>));
connect(switchButton<span class="operator">,</span> SIGNAL(clicked(<span class="type">bool</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(switchText()));
<span class="type"><a href="qpushbutton.html">QPushButton</a></span> <span class="operator">*</span>exitButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qpushbutton.html">QPushButton</a></span>(tr(<span class="string">"Exit"</span>));
connect(exitButton<span class="operator">,</span> SIGNAL(clicked(<span class="type">bool</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(close()));
<span class="type"><a href="qlabel.html">QLabel</a></span> <span class="operator">*</span>label <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>(tr(<span class="string">"Elided"</span>));
label<span class="operator">-</span><span class="operator">></span>setVisible(elidedText<span class="operator">-</span><span class="operator">></span>isElided());
connect(elidedText<span class="operator">,</span> SIGNAL(elisionChanged(<span class="type">bool</span>))<span class="operator">,</span> label<span class="operator">,</span> SLOT(setVisible(<span class="type">bool</span>)));</pre>
<p>The <tt>widthSlider</tt> and <tt>heightSlider</tt> specify the size of the <tt>elidedText</tt>. Since the y-axis is inverted, the <tt>heightSlider</tt> has to be inverted to act appropriately.</p>
<pre class="cpp"> widthSlider <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qslider.html">QSlider</a></span>(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Horizontal);
widthSlider<span class="operator">-</span><span class="operator">></span>setMinimum(<span class="number">0</span>);
connect(widthSlider<span class="operator">,</span> SIGNAL(valueChanged(<span class="type">int</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(onWidthChanged(<span class="type">int</span>)));
heightSlider <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qslider.html">QSlider</a></span>(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Vertical);
heightSlider<span class="operator">-</span><span class="operator">></span>setInvertedAppearance(<span class="keyword">true</span>);
heightSlider<span class="operator">-</span><span class="operator">></span>setMinimum(<span class="number">0</span>);
connect(heightSlider<span class="operator">,</span> SIGNAL(valueChanged(<span class="type">int</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(onHeightChanged(<span class="type">int</span>)));</pre>
<p>The components are all stored in a <a href="qgridlayout.html">QGridLayout</a>, which is made the layout of the <tt>TestWidget</tt>.</p>
<pre class="cpp"> <span class="type"><a href="qgridlayout.html">QGridLayout</a></span> <span class="operator">*</span>layout <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgridlayout.html">QGridLayout</a></span>();
layout<span class="operator">-</span><span class="operator">></span>addWidget(label<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>AlignCenter);
layout<span class="operator">-</span><span class="operator">></span>addWidget(switchButton<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">2</span>);
layout<span class="operator">-</span><span class="operator">></span>addWidget(exitButton<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">3</span>);
layout<span class="operator">-</span><span class="operator">></span>addWidget(widthSlider<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">3</span>);
layout<span class="operator">-</span><span class="operator">></span>addWidget(heightSlider<span class="operator">,</span> <span class="number">2</span><span class="operator">,</span> <span class="number">0</span>);
layout<span class="operator">-</span><span class="operator">></span>addWidget(elidedText<span class="operator">,</span> <span class="number">2</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">3</span><span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>AlignTop <span class="operator">|</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>AlignLeft);
setLayout(layout);</pre>
<p>On the Maemo platform, windows are stuck in landscape mode by default. With this attribute set, the window manager is aware that this window can be rotated.</p>
<pre class="cpp"> <span class="preprocessor">#ifdef Q_WS_MAEMO_5</span>
setAttribute(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>WA_Maemo5AutoOrientation<span class="operator">,</span> <span class="keyword">true</span>);
<span class="preprocessor">#endif</span>
}</pre>
<p>The <tt>widthSlider</tt> and <tt>heightSlider</tt> have the exact same length as the dimensions of the <tt>elidedText</tt>. The maximum value for both of them is thus their lengths, and each tick indicates one pixel.</p>
<pre class="cpp"> <span class="type">void</span> TestWidget<span class="operator">::</span>resizeEvent(<span class="type"><a href="qresizeevent.html">QResizeEvent</a></span> <span class="operator">*</span>event)
{
Q_UNUSED(event)
<span class="type">int</span> maxWidth <span class="operator">=</span> widthSlider<span class="operator">-</span><span class="operator">></span>width();
widthSlider<span class="operator">-</span><span class="operator">></span>setMaximum(maxWidth);
widthSlider<span class="operator">-</span><span class="operator">></span>setValue(maxWidth <span class="operator">/</span> <span class="number">2</span>);
<span class="type">int</span> maxHeight <span class="operator">=</span> heightSlider<span class="operator">-</span><span class="operator">></span>height();
heightSlider<span class="operator">-</span><span class="operator">></span>setMaximum(maxHeight);
heightSlider<span class="operator">-</span><span class="operator">></span>setValue(maxHeight <span class="operator">/</span> <span class="number">2</span>);
elidedText<span class="operator">-</span><span class="operator">></span>setFixedSize(widthSlider<span class="operator">-</span><span class="operator">></span>value()<span class="operator">,</span> heightSlider<span class="operator">-</span><span class="operator">></span>value());
}</pre>
<p>The <tt>switchText()</tt> slot simply cycles through all the available sample texts.</p>
<pre class="cpp"> <span class="type">void</span> TestWidget<span class="operator">::</span>switchText()
{
sampleIndex <span class="operator">=</span> (sampleIndex <span class="operator">+</span> <span class="number">1</span>) <span class="operator">%</span> textSamples<span class="operator">.</span>size();
elidedText<span class="operator">-</span><span class="operator">></span>setText(textSamples<span class="operator">.</span>at(sampleIndex));
}</pre>
<p>These slots set the width and height of the <tt>elided</tt> text, in response to changes in the sliders.</p>
<a name="the-function"></a>
<h2>The <tt>main()</tt> Function</h2>
<p>The <tt>main()</tt> function creates an instance of <tt>TestWidget</tt> fullscreen and enters the message loop.</p>
<pre class="cpp"> <span class="type">int</span> main( <span class="type">int</span> argc<span class="operator">,</span> <span class="type">char</span> <span class="operator">*</span>argv<span class="operator">[</span><span class="operator">]</span> )
{
<span class="type"><a href="qapplication.html">QApplication</a></span> application( argc<span class="operator">,</span> argv );
TestWidget w;
w<span class="operator">.</span>showFullScreen();
<span class="keyword">return</span> application<span class="operator">.</span>exec();
}</pre>
</div>
<!-- @@@widgets/elidedlabel -->
</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. Documentation contributions included herein are the copyrights of
their respective owners.</p>
<br />
<p>
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.</p>
<p>
Documentation sources may be obtained from <a href="http://www.qt-project.org">
www.qt-project.org</a>.</p>
<br />
<p>
Digia, Qt and their respective logos are trademarks of Digia Plc
in Finland and/or other countries worldwide. All other trademarks are property
of their respective owners. <a title="Privacy Policy"
href="http://en.gitorious.org/privacy_policy/">Privacy Policy</a></p>
</div>
<script src="scripts/functions.js" type="text/javascript"></script>
</body>
</html>
