fltk/documentation/Fl_Valuator.html
Michael R Sweet 4ddb739c13 Updated docos to match code.
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1999-03-09 18:42:05 +00:00

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<H2><A name=Fl_Valuator>class Fl_Valuator</A></H2>
<HR>
<H3>Class Hierarchy</H3>
<UL>
<PRE>
<A href=Fl_Widget.html#Fl_Widget>Fl_Widget</A>
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+----<B>Fl_Valuator</B>
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+----<A href=Fl_Adjuster.html#Fl_Adjuster>Fl_Adjuster</A>, <A href=Fl_Counter.html#Fl_Counter>Fl_Counter</A>, <A href=Fl_Dial.html#Fl_Dial>Fl_Dial</A>, <A href=Fl_Roller.html#Fl_Roller>Fl_Roller</A>,
<A href=Fl_Slider.html#Fl_Slider>Fl_Slider</A>, <A href=Fl_Value_Input.html#Fl_Value_Input>Fl_Value_Input</A>, <A href=Fl_Value_Output.html#Fl_Value_Output>Fl_Value_Output</A>,
</PRE>
</UL>
<H3>Include Files</H3>
<UL>
<PRE>
#include &lt;FL/Fl_Valuator.H&gt;
</PRE>
</UL>
<H3>Description</H3>
The <TT>Fl_Valuator</TT> class controls a single floating-point value
and provides a consistent interface to set the value, range, and step,
and insures that callbacks are done the same for every object.
<P>There are probably more of these classes in FLTK than any others: </P>
<P ALIGN=CENTER><IMG src=valuators.gif></P>
<P>In the above diagram each box surrounds an actual subclass. These
are further differentiated by setting the <A href=#Fl_Widget.type><TT>
type()</TT></A> of the widget to the symbolic value labeling the
widget. The ones labelled &quot;0&quot; are the default versions with a <TT>
type(0)</TT>. For consistency the symbol <TT>FL_VERTICAL</TT> is
defined as zero.</P>
<H3>Methods</H3>
<CENTER>
<TABLE width=90%>
<TR><TD align=left valign=top>
<UL>
<LI><A href=#Fl_Valuator.Fl_Valuator>Fl_Valuator</A></LI>
<LI><A href=#Fl_Valuator.~Fl_Valuator>~Fl_Valuator</A></LI>
<LI><A href=#Fl_Valuator.changed>changed</A></LI>
</UL>
</TD><TD align=left valign=top>
<UL>
<LI><A href=#Fl_Valuator.clamp>clamp</A></LI>
<LI><A href=#Fl_Valuator.clear_changed>clear_changed</A></LI>
<LI><A href=#Fl_Valuator.format>format</A></LI>
</UL>
</TD><TD align=left valign=top>
<UL>
<LI><A href=#Fl_Valuator.increment>increment</A></LI>
<LI><A href=#Fl_Valuator.maximum>maximum</A></LI>
<LI><A href=#Fl_Valuator.minimum>minimum</A></LI>
</UL>
</TD><TD align=left valign=top>
<UL>
<LI><A href=#Fl_Valuator.range>range</A></LI>
<LI><A href=#Fl_Valuator.round>round</A></LI>
<LI><A href=#Fl_Valuator.set_changed>set_changed</A></LI>
</UL>
</TD><TD align=left valign=top>
<UL>
<LI><A href=#Fl_Valuator.step>step</A></LI>
<LI><A href=#Fl_Valuator.value>value</A></LI>
</UL>
</TD></TR>
</TABLE>
</CENTER>
<H4><A name=Fl_Valuator.Fl_Valuator>Fl_Valuator::Fl_Valuator(int x, int
y, int w, int h, const char *label = 0)</A></H4>
Creates a new <TT>Fl_Valuator</TT> widget using the given position,
size, and label string. The default boxtype is <TT>FL_NO_BOX</TT>.
<H4><A name=Fl_Valuator.~Fl_Valuator>virtual Fl_Valuator::~Fl_Valuator()</A>
</H4>
Destroys the valuator.
<H4><A name=Fl_Valuator.value>double Fl_Valuator::value() const
<BR> int Fl_Valuator::value(double)</A></H4>
Get or set the current value. The new value is <I>not</I> clamped or
otherwise changed before storing it. Use <TT>clamp()</TT> or <TT>round()</TT>
to modify the value before calling this if you want. If the new value
is different than the current one the object is redrawn. The initial
value is zero.
<H4><A name=Fl_Valuator.minimum>double Fl_Valuator::minimum() const
<BR> void Fl_Valuator::minimum(double)</A></H4>
Gets or sets the minimum value for the valuator.
<H4><A name=Fl_Valuator.maximum>double Fl_Valuator::maximum() const
<BR> void Fl_Valuator::maximum(double)</A></H4>
Gets or sets the maximum value for the valuator.
<H4><A name=Fl_Valuator.range>void Fl_Valuator::range(double min,
double max);</A></H4>
Sets the minimum and maximum values for the valuator. When the user
manipulates the widget, the value is limited to this range. This
clamping is done <I>after</I> rounding to the step value (this makes a
difference if the range is not a multiple of the step).
<P>The minimum may be greater than the maximum. This has the effect of
&quot;reversing&quot; the object so the larger values are in the opposite
direction. This also switches which end of the filled sliders is
filled. </P>
<P>Some widgets consider this a &quot;soft&quot; range. This means they will
stop at the range, but if the user releases and grabs the control again
and tries to move it further, it is allowed. </P>
<P>The range may affect the display. You must <TT>redraw()</TT> the
widget after changing the range. </P>
<H4><A name=Fl_Valuator.step>double Fl_Valuator::step() const
<BR> void Fl_Valuator::step(double)
<BR> void Fl_Valuator::step(int A, int B)</A></H4>
Get or set the step value. As the user moves the mouse the value is
rounded to the nearest multiple of the step value. This is done <I>
before</I> clamping it to the range. For most objects the default step
is zero.
<P>For precision the step is stored as the ratio of two integers, A/B.
You can set these integers directly. Currently setting a floating
point value sets the nearest A/1 or 1/B value possible. </P>
<H4><A name=Fl_Valuator.format>int Fl_Valuator::format(char *)</A>
</H4>
Format the passed value to show enough digits so that for the current
step value. If the step has been set to zero then it does a <TT>%g</TT>
format. The characters are written into the passed buffer.
<H4><A name=Fl_Valuator.round>double Fl_Valuator::round(double)</A></H4>
Round the passed value to the nearest step increment. Does nothing if
step is zero.
<H4><A name=Fl_Valuator.clamp>double Fl_Valuator::clamp(double)</A></H4>
Clamp the passed value to the valuator range.
<H4><A name=Fl_Valuator.increment>double
Fl_Valuator::increment(double,int n)</A></H4>
Adds <TT>n</TT> times the step value to the passed value. If step was
set to zero it uses <TT>fabs(maximum() - minimum()) / 100</TT>.
<H4><A name=Fl_Valuator.changed>int Fl_Widget::changed() const</A></H4>
This value is true if the user has moved the slider. It is turned off
by <TT>value(x)</TT> and just before doing a callback (the callback can
turn it back on if desired).
<H4><A name=Fl_Valuator.set_changed>void Fl_Widget::set_changed()</A></H4>
Sets the <TT>changed()</TT> flag.
<H4><A name=Fl_Valuator.clear_changed>void Fl_Widget::clear_changed()</A>
</H4>
Clears the <TT>changed()</TT> flag. </BODY></HTML>