XtManageChild(3)

1XtManageChildren(3)              XT FUNCTIONS              XtManageChildren(3)
2
3
4

NAME

6       XtManageChildren, XtManageChild, XtUnmanageChildren, XtUnmanageChild,
7       XtChangeManagedSet, XtIsManaged - manage and unmanage children
8

SYNTAX

10       typedef Widget *WidgetList;
11
12       void XtManageChildren(WidgetList children, Cardinal num_children);
13
14       void XtManageChild(Widget child);
15
16       void XtUnmanageChildren(WidgetList children, Cardinal num_children);
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18       void XtUnmanageChild(Widget child);
19
20       void XtChangeManagedSet(WidgetList unmanage_children, Cardinal
21              num_unmanage_children, XtDoChangeProc do_change_proc, XtPointer
22              client_data, WidgetList manage_children, Cardinal num_man‐
23              age_children);
24
25       Boolean XtIsManaged(Widget widget);
26

ARGUMENTS

28       child     Specifies the child.
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30       children  Specifies a list of child widgets.
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32       num_children
33                 Specifies the number of children.
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35       widget    Specifies the widget.
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37       manage_children
38                 Specifies the list of widget children to add to the managed
39                 set.
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41       num_manage_children
42                 Specifies the number of entries in the manage_children list.
43
44       unmanage_children
45                 Specifies the list of widget children to remove from the man‐
46                 aged set.
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48       num_unmanage_children
49                 Specifies the number of entries in the unmanage_children
50                 list.
51
52       do_change_proc
53                 Specifies the post unmanage, pre manage hook procedure to
54                 invoke.
55
56       client_data
57                 Specifies the client data to be passed to the hook procedure.
58

DESCRIPTION

60       The XtManageChildren function performs the following:
61
62       ·    Issues an error if the children do not all have the same parent or
63            if the parent is not a subclass of compositeWidgetClass.
64
65       ·    Returns immediately if the common parent is being destroyed; oth‐
66            erwise, for each unique child on the list, XtManageChildren
67            ignores the child if it already is managed or is being destroyed
68            and marks it if not.
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70       ·    If the parent is realized and after all children have been marked,
71            it makes some of the newly managed children viewable:
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73            -    Calls the change_managed routine of the widgets' parent.
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75            -    Calls XtRealizeWidget on each previously unmanaged child that
76                 is unrealized.
77
78            -    Maps each previously unmanaged child that has map_when_man‐
79                 aged True.
80
81       Managing children is independent of the ordering of children and inde‐
82       pendent of creating and deleting children.  The layout routine of the
83       parent should consider children whose managed field is True and should
84       ignore all other children.  Note that some composite widgets, espe‐
85       cially fixed boxes, call XtManageChild from their insert_child proce‐
86       dure.
87
88       If the parent widget is realized, its change_managed procedure is
89       called to notify it that its set of managed children has changed.  The
90       parent can reposition and resize any of its children.  It moves each
91       child as needed by calling XtMoveWidget, which first updates the x and
92       y fields and then calls XMoveWindow if the widget is realized.
93
94       The XtManageChild function constructs a WidgetList of length one and
95       calls XtManageChildren.
96
97       The XtUnmanageChildren function performs the following:
98
99       ·    Issues an error if the children do not all have the same parent or
100            if the parent is not a subclass of compositeWidgetClass.
101
102       ·    Returns immediately if the common parent is being destroyed; oth‐
103            erwise, for each unique child on the list, XtUnmanageChildren per‐
104            forms the following:
105
106            -    Ignores the child if it already is unmanaged or is being
107                 destroyed and marks it if not.
108
109            -    If the child is realized, it makes it nonvisible by unmapping
110                 it.
111
112       ·    Calls the change_managed routine of the widgets' parent after all
113            children have been marked if the parent is realized.
114
115       XtUnmanageChildren does not destroy the children widgets.  Removing
116       widgets from a parent's managed set is often a temporary banishment,
117       and, some time later, you may manage the children again.
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119       The XtUnmanageChild function constructs a widget list of length one and
120       calls XtUnmanageChildren.
121
122       The XtChangeManagedSet function performs the following:
123
124       ·    Issues an error if the widgets specified in the manage_children
125            and the unmanage_children lists to no all have the same parent, or
126            if that parent is not a subclass of compositeWidgetClass.
127
128       ·    Returns immediately if the common parent is being destroyed.
129
130       ·    If no CompositeClassExtension is defined, or a CompositeClassEx‐
131            tension is defined but with an allows_change_managed_set field
132            with a value of False, and XtChangeManagedSet was invoked with a
133            non-NULL do_change_proc procedure then XtChangeManagedSet performs
134            the following:
135
136            -    Calls XtUnmanageChildren (unmanage_children, num_unman‐
137                 age_children).
138
139            -    Calls the do_change_proc specified.
140
141            -    Calls XtManageChildren (manage_children, num_manage_children)
142                 and then returns immediately.
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144       ·    Otherwise, if a CompositeClassExtension is defined with an
145            allows_change_managed_set field with a value of True, or if no
146            CompositeClassExtension is defined, and XtChangeManagedSetwas
147            do_change_proc procedure, then the following is performed:
148
149            -    For each child on the unmanage_children list; if the child is
150                 already unmanaged or is being destroyed it is ignored, other‐
151                 wise it is marked as being unmanaged and if it is realized it
152                 is made nonvisible by being unmapped.
153
154            -    If the do_change_proc procedure is non-NULL then it is
155                 invoked as specified.
156
157            -    For each child on the manage_children list; if the child is
158                 already managed or it is being destroyed it is ignored, oth‐
159                 erwise it is marked as managed
160
161       ·    If the parent is realized and after all children have been marked,
162            the change_managed method of the parent is invoked and subse‐
163            quently some of the newly managed children are made viewable by:
164
165            -    Calling XtRealizeWidget on each of the previously unmanaged
166                 child that is unrealized.
167
168            -    Mapping each previously unmanaged child that has
169                 map_when_managed True.
170
171       The XtIsManaged function returns True if the specified widget is of
172       class RectObj or any subclass thereof and is managed, or False other‐
173       wise.
174

NAME

SYNTAX

ARGUMENTS

DESCRIPTION

SEE ALSO