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<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.
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<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 behavior.
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<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.
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<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.
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<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.
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<p><a class="ulink" href="https://gnome.pages.gitlab.gnome.org/gtkmm/classGtk_1_1Scale.html" target="_top">Reference</a></p>
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