X Version 11 (1 September 1988) XtManageChildren(Xt)
NAME
XtManageChildren, XtManageChild, XtUnmanageChildren,
XtUnmanageChild - manage and unmanage children
SYNTAX
typedef Widget *WidgetList;
void XtManageChildren(children, num_children)
WidgetList children;
Cardinal num_children;
void XtManageChild(child)
Widget child;
void XtUnmanageChildren(children, num_children)
WidgetList children;
Cardinal num_children;
void XtUnmanageChild(child)
Widget child;
ARGUMENTS
child Specifies the child.
children Specifies a list of child widgets.
num_children
Specifies the number of children.
DESCRIPTION
The XtManageChildren function performs the following:
⊕ Issues an error if the children do not all have the
same parent or if the parent is not a subclass of
compositeWidgetClass.
⊕ Returns immediately if the common parent is being
destroyed; otherwise, for each unique child on the
list, XtManageChildren ignores the child if it already
is managed or is being destroyed and marks it if not.
⊕ If the parent is realized and after all children have
been marked, it makes some of the newly managed
children viewable:
- Calls the change_managed routine of the widgets'
parent.
- Calls XtRealizeWidget on each previously unmanaged
child that is unrealized.
- Maps each previously unmanaged child that has
map_when_managed True.
Managing children is independent of the ordering of children
and independent of creating and deleting children. The
layout routine of the parent should consider children whose
managed field is True and should ignore all other children.
Note that some composite widgets, especially fixed boxes,
call XtManageChild from their insert_child procedure.
If the parent widget is realized, its change_managed
procedure is called to notify it that its set of managed
children has changed. The parent can reposition and resize
any of its children. It moves each child as needed by
calling XtMoveWidget, which first updates the x and y fields
and then calls XMoveWindow if the widget is realized.
The XtManageChild function constructs a WidgetList of length
one and calls XtManageChildren.
The XtUnmanageChildren function performs the following:
⊕ Issues an error if the children do not all have the
same parent or if the parent is not a subclass of
compositeWidgetClass.
⊕ Returns immediately if the common parent is being
destroyed; otherwise, for each unique child on the
list, XtUnmanageChildren performs the following:
- Ignores the child if it already is unmanaged or is
being destroyed and marks it if not.
- If the child is realized, it makes it nonvisible
by unmapping it.
⊕ Calls the change_managed routine of the widgets' parent
after all children have been marked if the parent is
realized.
XtUnmanageChildren does not destroy the children widgets.
Removing widgets from a parent's managed set is often a
temporary banishment, and, some time later, you may manage
the children again.
The XtUnmanageChild function constructs a widget list of
length one and calls XtUnmanageChildren.
SEE ALSO
XtMapWidget(Xt), XtRealizeWidget(Xt)
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface
(printed 2/14/90) (1 September 1988) XtManageChildren(Xt)