cookbook: Added more explanation about setting y coord on scrollable

Added some extra explanation, referencing the sample code, to
try to make the scrollable actor example easier to follow. Basically
demonstrates the principles described in the paragraph about
setting the y coordinate for the scrollable actor, but using actual
numbers.
This commit is contained in:
Elliot Smith 2010-08-12 10:05:27 +01:00
parent a74d585fc5
commit 8db96675d4

View File

@ -635,6 +635,17 @@ _scroll_event_cb (ClutterActor *viewport,
<para>Scrolling down adds to the <code>y</code> coordinate <para>Scrolling down adds to the <code>y</code> coordinate
(but only up to a maximum value of <code>0.0</code>).</para> (but only up to a maximum value of <code>0.0</code>).</para>
<para>To see how this works in practice, look at
<link linkend="events-mouse-scroll-example">the code
sample</link>. There, the height of the scrollable actor is
set to <code>300</code> and the height of the viewport to
<code>150</code>. This means that the <code>y</code>
coordinate value for the scrollable actor will vary between
<code>-150.0</code> (<code>150 - 300</code>), making
its base visible and clipping the top; and
<code>0.0</code>, where its top is visible and its base
clipped.</para>
</listitem> </listitem>
<listitem> <listitem>