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<HTML><HEAD><TITLE>Aspect Frames</TITLE><METANAME="GENERATOR"CONTENT="Modular DocBook HTML Stylesheet Version 1.49"><LINKREL="HOME"TITLE="GTK+ 1.2 Tutorial"HREF="gtk-tut.html"><LINKREL="UP"TITLE="Container Widgets"HREF="ch-containerwidgets.html"><LINKREL="PREVIOUS"TITLE="Frames"HREF="sec-frames.html"><LINKREL="NEXT"TITLE="Paned Window Widgets"HREF="sec-panedwindowwidgets.html"></HEAD></head><body bgcolor="#FFFFFF" marginheight=0 marginwidth=0 width="100%"><table cellspacing=6 border=0 cellpadding=0 width="100%">  <tr>    <td bgcolor="#FFFFFF" valign=top nowrap>    <centeR><A HREF="/"><img src="/images/gtk-logo-rgb.gif" width=107 height=140 border=0></A>      <font face="helvetica,lucidia" color="#000000"><BR><BR><b>GTK+<BR>The GIMP Toolkit</b></center><BR><table width=100% cellspacing=0 cellpadding=2 border=0><tr><td bgcolor="#000000"><table width=100% cellspacing=0 cellpadding=4 border=0><tr><td bgcolor="#AAAAEE" nowrap><B>General</B></td></tr><tr><td bgcolor="#FFFFFF" nowrap><A HREF="/">Introduction</A><BR><A HREF="/screenshots/">Screenshots</A><br><A HREF="/download/">Download</A><br><A HREF="/mailinglists.html">Mailing Lists</A><BR><A HREF="/bindings.html">Language Bindings</A><BR><A HREF="http://gtk.themes.org/">Themes</A><BR><A HREF="/bugs.html">Bug Tracker</A><BR></td></tr></table></td></tr></table><BR>  <table width=100% cellspacing=0 cellpadding=2 border=0><tr><td bgcolor="#000000"><table width=100% cellspacing=0 cellpadding=4 border=0><tr><td bgcolor="#AAAAEE" nowrap><B>Documentation</B></td></tr><tr><td bgcolor="#FFFFFF" nowrap><A HREF="/faq/">FAQ</A><br><A HREF="/tutorial/">Tutorial</A><BR><A HREF="/api/">API Reference</A><br><A HREF="/books.html">Published Books</A><BR></td></tr></table></td></tr></table><BR>  <table width=100% cellspacing=0 cellpadding=2 border=0><tr><td bgcolor="#000000"><table width=100% cellspacing=0 cellpadding=4 border=0><tr><td bgcolor="#AAAAEE" nowrap><B>Projects</B></td></tr><tr><td bgcolor="#FFFFFF" nowrap><A HREF="http://www.pango.org/">Pango</A><BR><A HREF="http://sources.redhat.com/inti/">Inti</A><BR><A HREF="http://www.gnome.org/">GNOME</A><BR><A HREF="http://user.sgic.fi/~tml/gimp/win32/">GTK+ for Win32</A><br><A HREF="http://people.redhat.com/sopwith/gtkfb/">GtkFB (Framebuffer)</A><br><A HREF="http://www.directfb.org/gtk.xml">GTK+ on DirectFB</A><BR><A HREF="/beos/">GTK+ for BeOS</A></td></tr></table></td></tr></table><BR>  <table width=100% cellspacing=0 cellpadding=2 border=0><tr><td bgcolor="#000000"><table width=100% cellspacing=0 cellpadding=4 border=0><tr><td bgcolor="#AAAAEE" nowrap><B><B>Applications</B></B></td></tr><tr><td bgcolor="#FFFFFF" nowrap><A HREF="http://www.gimp.org/">GIMP</A><BR><A HREF="http://www.abiword.org/">Abiword</A><BR><A HREF="http://www.lysator.liu.se/~alla/dia/dia.html">Dia</A><BR><A HREF="http://glade.pn.org/">Glade</A><BR><A HREF="http://www.gnucash.org/">GnuCash</A><BR><A HREF="http://www.gnome.org/projects/gnumeric/">Gnumeric</A><BR><BR><A HREF="http://www.gnome.org/applist/">GNOME Software Map</A><br></td></tr></table></td></tr></table><BR>      </td>  <td bgcolor="#ffffff" valign=top width="99%"><font face="lucida,helvetica"><BODYCLASS="SECT1"BGCOLOR="#FFFFFF"TEXT="#000000"LINK="#0000FF"VLINK="#840084"ALINK="#0000FF"><DIVCLASS="NAVHEADER"><TABLEWIDTH="100%"BORDER="0"CELLPADDING="0"CELLSPACING="0"><TR><THCOLSPAN="3"ALIGN="center">GTK+ 1.2 Tutorial</TH></TR><TR><TDWIDTH="10%"ALIGN="left"VALIGN="bottom"><AHREF="sec-frames.html">&#60;&#60;&#60; Previous</A></TD><TDWIDTH="80%"ALIGN="center"VALIGN="bottom">Chapter 10. Container Widgets</TD><TDWIDTH="10%"ALIGN="right"VALIGN="bottom"><AHREF="sec-panedwindowwidgets.html">Next &#62;&#62;&#62;</A></TD></TR></TABLE><HRALIGN="LEFT"WIDTH="100%"></DIV><DIVCLASS="SECT1"><H1CLASS="SECT1"><ANAME="SEC-ASPECTFRAMES">10.6. Aspect Frames</A></H1><P>The aspect frame widget is like a frame widget, except that it alsoenforces the aspect ratio (that is, the ratio of the width to theheight) of the child widget to have a certain value, adding extraspace if necessary. This is useful, for instance, if you want topreview a larger image. The size of the preview should vary when theuser resizes the window, but the aspect ratio needs to always matchthe original image.</P><P>To create a new aspect frame use:</P><TABLEBORDER="0"BGCOLOR="#E0E0E0"WIDTH="100%"><TR><TD><PRECLASS="PROGRAMLISTING">GtkWidget *gtk_aspect_frame_new( const gchar *label,                                 gfloat       xalign,                                 gfloat       yalign,                                 gfloat       ratio,                                 gint         obey_child);</PRE></TD></TR></TABLE><P><TTCLASS="LITERAL">xalign</TT> and <TTCLASS="LITERAL">yalign</TT> specify alignment as with Alignmentwidgets. If <TTCLASS="LITERAL">obey_child</TT> is true, the aspect ratio of a childwidget will match the aspect ratio of the ideal size it requests.Otherwise, it is given by <TTCLASS="LITERAL">ratio</TT>.</P><P>To change the options of an existing aspect frame, you can use:</P><TABLEBORDER="0"BGCOLOR="#E0E0E0"WIDTH="100%"><TR><TD><PRECLASS="PROGRAMLISTING">void gtk_aspect_frame_set( GtkAspectFrame *aspect_frame,                           gfloat          xalign,                           gfloat          yalign,                           gfloat          ratio,                           gint            obey_child);</PRE></TD></TR></TABLE><P>As an example, the following program uses an AspectFrame to present adrawing area whose aspect ratio will always be 2:1, no matter how theuser resizes the top-level window.</P><TABLEBORDER="0"BGCOLOR="#E0E0E0"WIDTH="100%"><TR><TD><PRECLASS="PROGRAMLISTING">/* example-start aspectframe aspectframe.c */#include &#60;gtk/gtk.h&#62;   int main( int argc,          char *argv[] ){    GtkWidget *window;    GtkWidget *aspect_frame;    GtkWidget *drawing_area;    gtk_init (&#38;argc, &#38;argv);       window = gtk_window_new (GTK_WINDOW_TOPLEVEL);    gtk_window_set_title (GTK_WINDOW (window), "Aspect Frame");    gtk_signal_connect (GTK_OBJECT (window), "destroy",                        GTK_SIGNAL_FUNC (gtk_main_quit), NULL);    gtk_container_set_border_width (GTK_CONTAINER (window), 10);       /* Create an aspect_frame and add it to our toplevel window */       aspect_frame = gtk_aspect_frame_new ("2x1", /* label */                                         0.5, /* center x */                                         0.5, /* center y */                                         2, /* xsize/ysize = 2 */                                         FALSE /* ignore child's aspect */);       gtk_container_add (GTK_CONTAINER(window), aspect_frame);    gtk_widget_show (aspect_frame);       /* Now add a child widget to the aspect frame */       drawing_area = gtk_drawing_area_new ();       /* Ask for a 200x200 window, but the AspectFrame will give us a 200x100     * window since we are forcing a 2x1 aspect ratio */    gtk_widget_set_usize (drawing_area, 200, 200);    gtk_container_add (GTK_CONTAINER(aspect_frame), drawing_area);    gtk_widget_show (drawing_area);       gtk_widget_show (window);    gtk_main ();    return 0;}/* example-end */</PRE></TD></TR></TABLE></DIV><DIVCLASS="NAVFOOTER"><HRALIGN="LEFT"WIDTH="100%"><TABLEWIDTH="100%"BORDER="0"CELLPADDING="0"CELLSPACING="0"><TR><TDWIDTH="33%"ALIGN="left"VALIGN="top"><AHREF="sec-frames.html">&#60;&#60;&#60; Previous</A></TD><TDWIDTH="34%"ALIGN="center"VALIGN="top"><AHREF="gtk-tut.html">Home</A></TD><TDWIDTH="33%"ALIGN="right"VALIGN="top"><AHREF="sec-panedwindowwidgets.html">Next &#62;&#62;&#62;</A></TD></TR><TR><TDWIDTH="33%"ALIGN="left"VALIGN="top">Frames</TD><TDWIDTH="34%"ALIGN="center"VALIGN="top"><AHREF="ch-containerwidgets.html">Up</A></TD><TDWIDTH="33%"ALIGN="right"VALIGN="top">Paned Window Widgets</TD></TR></TABLE></DIV>        </td>    </tr></table>  </td>  </tr></table></body></BODY></HTML>
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