system, a widget's window may not appear on the screen	immediatly after one calls <ahref="/usr/share/gtk-doc/html/gdk/gdk-Windows.html#gdk-window-show"><code class="function">gdk_window_show()</code></a>:	you must wait for the corresponding map <a class="glossterm" href="glossary.html#event"><em class="glossterm">event</em></a> to be received.  You can do	this with the <a class="link" href="GtkWidget.html#GtkWidget-map-event"><code class="methodname">GtkWidget::map-event</code>	signal</a>.      </p></dd><dt><a name="model-column"></a>model column</dt><dd><p>        A column in a tree model, holding data of a certain type.         The types which can be stored in the columns of a model         have to be specified when the model is constructed, see         e.g. <a class="link" href="GtkListStore.html#gtk-list-store-new"><code class="function">gtk_list_store_new()</code></a>.      </p><p>See Also 	<a class="glossterm" href="glossary.html#view-column"><em class="glossterm">view column</em></a>      .</p></dd><dt><a name="model-view"></a>model-view widget</dt><dd><p>        These widgets follow the well-known model-view pattern, which separates        the data (the model) to be displayed from the component which does the         actual visualization (the view). Examples of this pattern in GTK+ are         the <a class="link" href="GtkTreeView.html" title="GtkTreeView"><span class="type">GtkTreeView</span></a>/<a class="link" href="GtkTreeModel.html" title="GtkTreeModel"><span class="type">GtkTreeModel</span></a> and <a class="link" href="GtkTextView.html" title="GtkTextView"><span class="type">GtkTextView</span></a>/<a class="link" href="GtkTextBuffer.html" title="GtkTextBuffer"><span class="type">GtkTextBuffer</span></a>      </p><p>        One important advantage of this pattern is that it is possible to         display the same model in multiple views; another one that the         separation of the model allows a great deal of flexibility, as         demonstrated by e.g. <a class="link" href="GtkTreeModelSort.html" title="GtkTreeModelSort"><span class="type">GtkTreeModelSort</span></a> or <a class="link" href="GtkTreeModelFilter.html" title="GtkTreeModelFilter"><span class="type">GtkTreeModelFilter</span></a>.      </p></dd><dt><a name="no-window"></a>no-window widget</dt><dd><p>	A widget that does not have a GdkWindow of its own on which to	draw its contents, but rather shares its <a class="glossterm" href="glossary.html#parent"><em class="glossterm">parent's</em></a>.  Such a widget has the	<a class="link" href="GtkWidget.html#GTK-NO-WINDOW:CAPS"><code class="literal">GTK_NO_WINDOW</code></a> <a class="link" href="GtkWidget.html#GtkWidgetFlags">flag</a> set, and         can be tested with the <a class="link" href="GtkWidget.html#GTK-WIDGET-NO-WINDOW:CAPS"><code class="function">GTK_WIDGET_NO_WINDOW()</code></a> macro.      </p></dd><dt><a name="parent"></a>parent</dt><dd><p>	A <a class="glossterm" href="glossary.html#widget"><em class="glossterm">widget's</em></a> parent is	the <a class="glossterm" href="glossary.html#container"><em class="glossterm">container</em></a>	inside which it resides.      </p></dd><dt><a name="realization"></a>realization</dt><dd><p>	This is the step in a <a class="glossterm" href="glossary.html#widget"><em class="glossterm">widget's</em></a> life cycle where it	creates its own GdkWindow, or otherwise associates itself with	its <a class="glossterm" href="glossary.html#parent"><em class="glossterm">parent's</em></a>	GdkWindow.  If the widget has its own window, then it must	also attach a <a class="glossterm" href="glossary.html#style"><em class="glossterm">style</em></a> to	it.  A widget becomes unrealized by destroying its associated	GdkWindow.  When a widget is realized, it must turn on its	<a class="link" href="GtkWidget.html#GTK-REALIZED:CAPS"><code class="literal">GTK_REALIZED</code></a> <a class="link" href="GtkWidget.html#GtkWidgetFlags">flag</a>.      </p><p>	Widgets that don't own the GdkWindow on which they draw are	called <a class="glossterm" href="glossary.html#no-window"><em class="glossterm">no-window widgets</em></a>.          This can be tested with the <a class="link" href="GtkWidget.html#GTK-WIDGET-NO-WINDOW:CAPS"><code class="function">GTK_WIDGET_NO_WINDOW()</code></a> macro.  Normally,         these widgets draw on their parent's GdkWindow.      </p><p>	Note that when a widget creates a window in its <code class="methodname">::<GTKDOCLINK HREF="realize"><code class="function">realize()</code></code></GTKDOCLINK>	handler, it does not actually show the window.  That is, the	window's structure is just created in memory.  The widget	actually shows the window when it gets <a class="glossterm" href="glossary.html#mapping"><em class="glossterm">mapped</em></a>.      </p></dd><dt><a name="requisition"></a>requisition</dt><dd><p>	The size requisition of a <a class="glossterm" href="glossary.html#widget"><em class="glossterm">widget</em></a> is the minimum amount of	space it requests from its <a class="glossterm" href="glossary.html#parent"><em class="glossterm">parent</em></a>.  Once the parent computes	the widget's final size, it gives it its <a class="glossterm" href="glossary.html#allocation"><em class="glossterm">size allocation</em></a>.      </p><p>See Also 	<a class="glossterm" href="glossary.html#allocation"><em class="glossterm">allocation</em></a>      .</p></dd><dt><a name="screen"></a>screen</dt><dd><p>	GDK inherited the concept of screen from the X window system,         which considers a screen to be a rectangular area, on which         applications may place their windows. Screens under X may have         quite dissimilar <a class="glossterm" href="glossary.html#visual"><em class="glossterm">visuals</em></a>.        Each screen can stretch across multiple physical monitors.      </p><p>        In GDK, screens are represented by <ahref="/usr/share/gtk-doc/html/gdk/GdkScreen.html"><span class="type">GdkScreen</span></a> objects.      </p></dd><dt><a name="style"></a>style</dt><dd><p>        A style encapsulates what GTK+ needs to know in order to draw        a widget. Styles can be modified with         <a class="link" href="gtk-Resource-Files.html" title="Resource Files">resource files</a>.      </p></dd><dt><a name="toplevel"></a>toplevel</dt><dd><p>	A <a class="glossterm" href="glossary.html#widget"><em class="glossterm">widget</em></a> that does not	require a <a class="glossterm" href="glossary.html#parent"><em class="glossterm">parent</em></a> container.          The only toplevel widgets in GTK+ are <a class="link" href="GtkWindow.html" title="GtkWindow"><span class="type">GtkWindow</span></a> and widgets derived from it.      </p><p>See Also 	<a class="glossterm" href="glossary.html#container"><em class="glossterm">container</em></a>      .</p></dd><dt><a name="unmap"></a>unmap</dt><dd><p>See <a class="glossterm" href="glossary.html#mapping"><em class="glossterm">mapping</em></a>.</p></dd><dt><a name="unrealize"></a>unrealize</dt><dd><p>See <a class="glossterm" href="glossary.html#realization"><em class="glossterm">realization</em></a>.</p></dd><dt><a name="view-column"></a>view column</dt><dd><p>        A displayed column in a tree view, represented by a        <a class="link" href="GtkTreeViewColumn.html" title="GtkTreeViewColumn"><span class="type">GtkTreeViewColumn</span></a> object.      </p><p>See Also 	<a class="glossterm" href="glossary.html#model-column"><em class="glossterm">model column</em></a>      .</p></dd><dt><a name="visual"></a>visual</dt><dd><p>        A visual describes how color information is stored in pixels.        A <a class="glossterm" href="glossary.html#screen"><em class="glossterm">screen</em></a> may support        multiple visuals. On modern hardware, the most common visuals        are truecolor visuals, which store a fixed number of bits         (typically 8) for the red, green and blue components of a color.      </p><p>        On ancient hardware, one may still meet indexed visuals, which         store color information as an index into a color map, or even        monochrome visuals.       </p></dd><dt><a name="widget"></a>widget</dt><dd><p>	A control in a graphical user interface.  Widgets can draw	themselves and process events from the mouse and keyboard.	Widget types include buttons, menus, text entry lines, and	lists.  Widgets can be arranged into <a class="glossterm" href="glossary.html#container"><em class="glossterm">containers</em></a>, and these take	care of assigning the <a class="glossterm" href="glossary.html#geometry"><em class="glossterm">geometry</em></a> of the widgets:  every	widget thus has a parent except those widgets which are	<a class="glossterm" href="glossary.html#toplevel"><em class="glossterm">toplevels</em></a>.  The base	class for widgets is <a class="link" href="GtkWidget.html" title="GtkWidget"><span class="type">GtkWidget</span></a>.      </p><p>See Also 	<a class="glossterm" href="glossary.html#container"><em class="glossterm">container</em></a>      .</p></dd></dl></div></body></html>