<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Scale Widgets</title> <link rel="stylesheet" type="text/css" href="style.css"> <meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> <link rel="home" href="index.html" title="Programming with gtkmm 3"> <link rel="up" href="chapter-range-widgets.html" title="Chapter 6. Range Widgets"> <link rel="prev" href="chapter-range-widgets.html" title="Chapter 6. Range Widgets"> <link rel="next" href="sec-range-example.html" title="Example"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr><th colspan="3" align="center">Scale Widgets</th></tr> <tr> <td width="20%" align="left"> <a accesskey="p" href="chapter-range-widgets.html"><img src="icons/prev.png" alt="Prev"></a> </td> <th width="60%" align="center">Chapter 6. Range Widgets</th> <td width="20%" align="right"> <a accesskey="n" href="sec-range-example.html"><img src="icons/next.png" alt="Next"></a> </td> </tr> </table> <hr> </div> <div class="sect1"> <div class="titlepage"><div><div><h2 class="title" style="clear: both"> <a name="sec-scale-widgets"></a>Scale Widgets</h2></div></div></div> <p> <code class="classname">Gtk::Scale</code> widgets (or "sliders") allow the user to visually select and manipulate a value within a specific range. You might use one, for instance, to adjust the magnification level on a zoomed preview of a picture, or to control the brightness of a colour, or to specify the number of minutes of inactivity before a screensaver takes over the screen. </p> <p> As with <code class="classname">Scrollbar</code>s, the orientation can be either horizontal or vertical. The default constructor creates an <code class="classname">Adjustment</code> with all of its values set to <code class="literal">0.0</code>. This isn't useful so you will need to set some <code class="classname">Adjustment</code> details to get meaningful behaviour. </p> <div class="sect2"> <div class="titlepage"><div><div><h3 class="title"> <a name="scale-useful-methods"></a>Useful methods</h3></div></div></div> <p> <code class="classname">Scale</code> widgets can display their current value as a number next to the trough. By default they show the value, but you can change this with the <code class="methodname">set_draw_value()</code> method. </p> <p> The value displayed by a scale widget is rounded to one decimal point by default, as is the <code class="literal">value</code> field in its <code class="classname">Gtk::Adjustment</code>. You can change this with the <code class="methodname">set_digits()</code> method. </p> <p> Also, the value can be drawn in different positions relative to the trough, specified by the <code class="methodname">set_value_pos()</code> method. </p> <p><a class="ulink" href="http://developer.gnome.org/gtkmm/3.24/classGtk_1_1Scale.html" target="_top">Reference</a></p> </div> </div> <div class="navfooter"> <hr> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"> <a accesskey="p" href="chapter-range-widgets.html"><img src="icons/prev.png" alt="Prev"></a> </td> <td width="20%" align="center"><a accesskey="u" href="chapter-range-widgets.html"><img src="icons/up.png" alt="Up"></a></td> <td width="40%" align="right"> <a accesskey="n" href="sec-range-example.html"><img src="icons/next.png" alt="Next"></a> </td> </tr> <tr> <td width="40%" align="left" valign="top">Chapter 6. Range Widgets </td> <td width="20%" align="center"><a accesskey="h" href="index.html"><img src="icons/home.png" alt="Home"></a></td> <td width="40%" align="right" valign="top"> Example</td> </tr> </table> </div> </body> </html>
