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<h1 class="title">Widgets Tutorial - Creating a Window</h1>
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<p>Files:</p>
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<li><a href="tutorials-widgets-toplevel-main-cpp.html">tutorials/widgets/toplevel/main.cpp</a></li>
<li><a href="tutorials-widgets-toplevel-toplevel-pro.html">tutorials/widgets/toplevel/toplevel.pro</a></li>
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<p>If a widget is created without a parent, it is treated as a window, or <i>top-level widget</i>, when it is shown. Since it has no parent object to ensure that it is deleted when no longer needed, it is up to the developer to keep track of the top-level widgets in an application.</p>
<p>In the following example, we use <a href="qwidget.html">QWidget</a> to create and show a window with a default size:</p>
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<tr valign="top" class="odd"><td ><pre class="cpp"> <span class="preprocessor">#include <QtGui></span>
<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>)
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window<span class="operator">.</span>resize(<span class="number">320</span><span class="operator">,</span> <span class="number">240</span>);
window<span class="operator">.</span>show();
window<span class="operator">.</span>setWindowTitle(
<span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>translate(<span class="string">"toplevel"</span><span class="operator">,</span> <span class="string">"Top-level widget"</span>));
<span class="keyword">return</span> app<span class="operator">.</span>exec();
}</pre>
</td><td ><img src="images/widgets-tutorial-toplevel.png" alt="" /></td></tr>
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</div><p>To create a real GUI, we need to place widgets inside the window. To do this, we pass a <a href="qwidget.html">QWidget</a> instance to a widget's constructor, as we will demonstrate in the next part of this tutorial.</p>
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