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>Freevo Plugin Writing HOWTO: Writing your own plugins for Freevo</TH
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NAME="AEN109"
>2.5. Using the skin</A
></H1
><P
>	Some plugins may want to draw something on the screen. One example is
	the weather plugin (external plugin, download it from
	<CODE
CLASS="VARNAME"
>http://freevo.sf.net/addons/</CODE
>). Since this has
	nothing to do with the normal menu system, such plugins also need an
	eventhandler to react on buttons. 
      </P
><P
>	Since Freevo knows nothing about which elements should be displayed
	and were to put them, the plugin needs to define a fxd file in
	<TT
CLASS="FILENAME"
>share/skins/plugins</TT
> with the needed
	information. 
      </P
><P
>	<PRE
CLASS="PROGRAMLISTING"
>&#60;?xml version="1.0" ?&#62;
&#60;freevo&#62;
  &#60;skin geometry="800x600"&#62;
    &#60;foo&#62;
      &#60;screen layout="screen" x="0" y="0" width="800" height="600"/&#62;
      &#60;title .../&#62;
      &#60;view  .../&#62;
    &#60;/foo&#62;
  &#60;/skin&#62;
&#60;/freevo&#62;
	</PRE
>
      </P
><P
>	Now the freevo skin has fxd information about the type
	<CODE
CLASS="VARNAME"
>foo</CODE
>, but doesn't know which areas are allowed (ok,
	the skin could guess it). So the plugin needs to call
	<PRE
CLASS="PROGRAMLISTING"
>skin.register('foo', ('screen', 'title', 'view', 'plugin'))</PRE
> 
	once. Now the plugin can call
	<PRE
CLASS="PROGRAMLISTING"
>skin.draw('foo', item)</PRE
> to draw
	<CODE
CLASS="VARNAME"
>item</CODE
> with the settings of <CODE
CLASS="VARNAME"
>foo</CODE
>. 
      </P
><P
>So far so good, but it may happen that the plugin needs an area
	which isn't defined right now. The default areas for Freevo are
	<CODE
CLASS="VARNAME"
>screen</CODE
>, <CODE
CLASS="VARNAME"
>title</CODE
>,
	<CODE
CLASS="VARNAME"
>subtitle</CODE
>, <CODE
CLASS="VARNAME"
>listing</CODE
>,
	<CODE
CLASS="VARNAME"
>info</CODE
>, <CODE
CLASS="VARNAME"
>view</CODE
> and
	<CODE
CLASS="VARNAME"
>plugin</CODE
>. The plugin area is used for smaller
	plugins to draw on the screen, e.g. the idlebar.
      </P
><P
>	To create an area of your own, you first need to define it in the fxd
	file:
      </P
><P
>	<PRE
CLASS="PROGRAMLISTING"
>&#60;?xml version="1.0" ?&#62;
&#60;freevo&#62;
  &#60;skin geometry="800x600"&#62;
    &#60;foo&#62;
      &#60;screen layout="screen" x="0" y="0" width="800" height="600"/&#62;
      &#60;foo_area layout="foo" x="10" y="100" width="300" height="200"/&#62;
    &#60;/foo&#62;
  &#60;/skin&#62;

  &#60;layout label="foo"&#62;
    &#60;background&#62;
      ...
    &#60;/background&#62;
    &#60;content ...&#62;
      ...
    &#60;/content&#62;
  &#60;/layout&#62;
&#60;/freevo&#62;
	</PRE
>
      </P
><P
>	Now the skin has fxd information about an area
	<CODE
CLASS="VARNAME"
>foo</CODE
>. The skin knows were it is and can also draw
	the background of the layout. But it needs an object to draw the real
	content. The following example defines a class which inherits from
	<CODE
CLASS="VARNAME"
>skin.Area</CODE
>. It defines itself as class to draw
	<CODE
CLASS="VARNAME"
>foo_area</CODE
>. The skin now calls the function
	<CODE
CLASS="FUNCTION"
>update_content_needed</CODE
> to check if the area needs
	an update (return <CODE
CLASS="VARNAME"
>True</CODE
> or
	<CODE
CLASS="VARNAME"
>False</CODE
>). When Freevo knows that an update is
	needed, this function may not be called after all. The real work is
	done is <CODE
CLASS="FUNCTION"
>update_content</CODE
>. 
      </P
><P
>	(add more doc here)
      </P
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freevo-doc 1.9.2b2-4.2 / usr / share / doc / freevo / plugin_writing / x109.html
