mirror of https://github.com/fltk/fltk
85 lines
4.1 KiB
HTML
85 lines
4.1 KiB
HTML
<HTML><BODY>
|
|
<!-- NEW PAGE -->
|
|
<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 <FL/Fl_Choice.H>
|
|
</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 item's callback is done with
|
|
the menu_button as the <TT>Fl_Widget*</TT> argument. If the
|
|
item does not have a callback the menu_button's callback is done
|
|
instead. </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>
|
|
<P ALIGN=CENTER><IMG src="choice.gif" ALT="Fl_Choice widget."></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>
|