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<HTML>
<HEAD>
<TITLE>Fl_Free</TITLE>
</HEAD>
<BODY>
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<H2><A name=Fl_Free>class Fl_Free</A></H2>
<HR>
<H3>Class Hierarchy</H3>
<UL>
<PRE>
<A href=Fl_Widget.html#Fl_Widget>Fl_Widget</A>
|
+----<B>Fl_Free</B>
</PRE>
</UL>
<H3>Include Files</H3>
<UL>
<PRE>
#include &lt;FL/Fl_Free.H&gt;
</PRE>
</UL>
<H3>Description</H3>
Emulation of the Forms &quot;free&quot; widget. This emulation allows the free
demo to run, and appears to be useful for porting programs written in
Forms which use the free widget or make subclasses of the Forms
widgets.
<P>There are five types of free, which determine when the handle
function is called: </P>
<UL>
<PRE>
#define FL_NORMAL_FREE 1
#define FL_SLEEPING_FREE 2
#define FL_INPUT_FREE 3
#define FL_CONTINUOUS_FREE 4
#define FL_ALL_FREE 5
</PRE>
</UL>
<P>An FL_INPUT_FREE accepts FL_FOCUS events. A FL_CONTINUOUS_FREE sets
a timeout callback 100 times a second and provides a FL_STEP event,
this has obvious detrimental effects on machine performance.
FL_ALL_FREE does both. FL_SLEEPING_FREE are deactivated. </P>
<H3>Methods</H3>
<UL>
<LI><A href=#Fl_Free.Fl_Free>Fl_Free</A></LI>
<LI><A href=#Fl_Free.~Fl_Free>~Fl_Free</A></LI>
</UL>
<H4><A name=Fl_Free.Fl_Free>Fl_Free(uchar type, int, int, int, int,
const char*l, FL_HANDLEPTR hdl)</A></H4>
The constructor takes both the <TT>type</TT> and the <TT>handle</TT>
function. The handle function should be declared as follows:
<UL>
<PRE>
int
handle_function(Fl_Widget *w,
int event,
float event_x,
float event_y,
char key)
</PRE>
</UL>
This function is called from the the <TT>handle()</TT> method in
response to most events, and is called by the <TT>draw()</TT> method.
The <TT>event</TT> argument contains the event type:
<UL>
<PRE>
// old event names for compatability:
#define FL_MOUSE FL_DRAG
#define FL_DRAW 0
#define FL_STEP 9
#define FL_FREEMEM 12
#define FL_FREEZE FL_UNMAP
#define FL_THAW FL_MAP
</PRE>
</UL>
<H4><A name=Fl_Free.~Fl_Free>virtual Fl_Free::~Fl_Free()</A></H4>
The destructor will call the handle function with the event <TT>
FL_FREE_MEM</TT>. </BODY></HTML>