XtManageChildren(Xt) X Version 11 (Release 5) XtManageChildren(Xt)
6 January 1993
Name
XtManageChildren - 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.
numchildren
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; other-
wise, 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 indepen-
dent 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; other-
wise, 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 widg-
ets 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) and XtRealizeWidget(Xt).
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface