fltk/documentation/Fl_Choice.html
Michael R Sweet d7b88a3bcc Updated all links so they work between files.
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<H2><A name=Fl_Choice>class Fl_Choice</A></H2>
<HR>
<H3>Class Hierarchy</H3>
<UL>
<PRE>
<A href=Fl_Menu_.html#Fl_Menu_>Fl_Menu_</A>
|
+----<B>Fl_Choice</B>
</PRE>
</UL>
<H3>Include Files</H3>
<UL>
<PRE>
#include &lt;FL/Fl_Choice.H&gt;
</PRE>
</UL>
<H3>Description</H3>
This is a button that when pushed pops up a menu (or hierarchy of
menus) defined by an array of <A href=Fl_Menu_Item.html#Fl_Menu_Item><TT>
Fl_Menu_Item</TT></A> objects. Motif calls this an OptionButton.
<P>The only difference between this and a <A href=Fl_Menu_Button.html#Fl_Menu_Button>
<TT>Fl_Menu_Button</TT></A> is that the name of the most recent chosen
menu item is displayed inside the box, while the label is displayed
outside the box. However, since the use of this is most often to
control a single variable rather than do individual callbacks, some of
the <TT>Fl_Menu_Button</TT> methods are redescribed here in those
terms. </P>
<P>When the user picks an item off the menu the <TT>value()</TT> is set
to that item and then the callback is done. </P>
<P>All three mouse buttons pop up the menu. The Forms behavior of the
first two buttons to increment/decrement the choice is not implemented.
This could be added with a subclass, however. </P>
<P>The menu will also pop up in response to shortcuts indicated by
putting a ''character in the <TT>label()</TT>. See <A href=Fl_Button.html#Fl_Button>
<TT>Fl_Button</TT></A> for a description of this. </P>
<P>Typing the <TT>shortcut()</TT> of any of the items will do exactly
the same as when you pick the item with the mouse. The ''character in
item names are only looked at when the menu is popped up, however. </P>
<H3>Methods</H3>
<UL>
<LI><A href=#Fl_Choice.Fl_Choice>Fl_Choice</A></LI>
<LI><A href=#Fl_Choice.~Fl_Choice>~Fl_Choice</A></LI>
<LI><A href=#Fl_Choice.clear_changed>clear_changed</A></LI>
<LI><A href=#Fl_Choice.changed>changed</A></LI>
<LI><A href=#Fl_Choice.down_box>down_box</A></LI>
<LI><A href=#Fl_Choice.set_changed>set_changed</A></LI>
<LI><A href=#Fl_Choice.value>value</A></LI>
</UL>
<H4><A name=Fl_Choice.Fl_Choice>Fl_Choice::Fl_Choice(int x, int y, int
w, int h, const char *label = 0)</A></H4>
Creates a new <TT>Fl_Choice</TT> widget using the given position,
size, and label string. The default boxtype is <TT>FL_UP_BOX</TT>.
<P>The constructor sets <TT>menu()</TT> to <TT>NULL</TT>. See <A href=Fl_Menu_.html#Fl_Menu_>
<TT>Fl_Menu_</TT></A> for the methods to set or change the menu. </P>
<H4><A name=Fl_Choice.~Fl_Choice>virtual Fl_Choice::~Fl_Choice()</A></H4>
The destructor removes the <TT>Fl_Choice</TT> widget and all of its
menu items.
<H4><A name=Fl_Choice.value>int Fl_Choice::value() const
<BR> int Fl_Choice::value(int)
<BR> int Fl_Choice::value(const Fl_Menu *)</A></H4>
The value is the index into the <TT>Fl_Menu</TT> array of the last
item chosen by the user. It is zero initially. You can set it as an
integer, or set it with a pointer to a menu item. The set routines
return non-zero if the new value is different than the old one.
Changing it causes a <TT>redraw()</TT>.
<H4><A name=Fl_Choice.changed>int Fl_Widget::changed() const</A></H4>
This value is true if the user picks a different value. <I>It is
turned off by <TT>value()</TT> and just before doing a callback (the
callback can turn it back on if desired).</I>
<H4><A name=Fl_Choice.set_changed>void Fl_Widget::set_changed()</A></H4>
This method sets the <TT>changed()</TT> flag.
<H4><A name=Fl_Choice.clear_changed>void Fl_Widget::clear_changed()</A></H4>
This method clears the <TT>changed()</TT> flag.
<H4><A name=Fl_Choice.down_box>Fl_Boxtype Fl_Choice::down_box() const
<BR> void Fl_Choice::down_box(Fl_Boxtype b)</A></H4>
The first form gets the current down box, which is used when the menu
is popped up. The default down box type is <TT>FL_DOWN_BOX</TT> The
second form sets the current down box type to <TT>b</TT>. </BODY></HTML>