Class Hierarchy
Fl_Widget
|
+----Fl_Group
|
+----Fl_Pack, Fl_Scroll, Fl_Tabs, Fl_Tile, Fl_Window
Include Files
#include <FL/Fl_Group.H>
Description
The Fl_Group class is the FLTK container widget. It maintains
an array of child widgets. These children can themselves be any widget
including Fl_Group. The most important subclass of Fl_Group
is Fl_Window, however
groups can also be used to control radio buttons or to enforce resize
behavior.
Methods
Creates a new Fl_Group widget using the given position, size,
and label string. The default boxtype is FL_NO_BOX.
The destructor also deletes all the children. This allows a
whole tree to be deleted at once, without having to keep a pointer to
all the children in the user code. A kludge has been done so the
Fl_Group and all of it's children can be automatic (local)
variables, but you must declare the Fl_Groupfirst, so
that it is destroyed last.
Adds a widget to the group at the end of the child array.
Adds a widget to the group and makes it the resizable widget.
Returns a pointer to the array of children. This pointer can change
when children are added or removed!
begin() sets the current group so you can build the widget
tree by just constructing the widgets. begin() is
automatically called by the constructor for Fl_Group (and thus for
Fl_Window as well). begin() does current(this).
Don't forget to end() the group or window!
Returns child n, where 0
.
Returns how many child widgets the group has.
current() returns the currently active group in the widget
tree. To prevent widgets from being added to a group, call current()
with a NULL group.
end() does current(this->parent()). Any new widgets
added to the widget tree will be added to the parent of the group.
Searches the child array for the widget and returns the index. Returns children() if the widget is
NULL or not found.
Inserts a widget into the child array. It is put at index n
which must be less or equal to children(). The second version does a
find(beforethis) and inserts using that index.
Removes a widget from the group. This does nothing if the widget is
not currently a child of this group.
The resizable widget defines the resizing box for the group. When the
group is resized it calculates a new size and position for all of its
children. Widgets that are horizontally or vertically inside the
dimensions of the box are scaled to the new size. Widgets outside the
box are moved.
In these examples the gray area is the resizable:
The resizable may be set to the group itself (this is the default
value for an Fl_Group, although NULL is the default
for an Fl_Window), in which case all the contents are resized.
If the resizable is NULL then all widgets remain a fixed size
and distance from the top-left corner.
It is possible to achieve any type of resize behavior by using an
invisible Fl_Box as the resizable and/or by using a hierarchy
of child Fl_Group's.