XtSetSubvalues() XtSetSubvalues()
Name
XtSetSubvalues - copy resource settings from an ArgList to a subpart resource structure.
Synopsis
void XtSetSubvalues(base, resources, num_resources, args, num_args)
XtPointer base;
XtResourceList resources;
Cardinal num_resources;
ArgList args;
Cardinal num_args;
Inputs
base Specifies the base address of the subpart data structure into which the resources should be written.
resources Specifies the subpart resource list.
num_resources
Specifies the number of resources in the resource list.
args Specifies an argument list of name/value pairs that contain the resource settings to be copied into the subpart data structure.
num_args Specifies the number of arguments in the argument list.
Description
XtSetSubvalues() copies the values of named resources from args into the structure pointed to by base. The resource list resources speci-
fies the size of each resource in this structure, and its offset from base. The name of each resource in args is looked up in this
resource list, and the resource's specified size and offset are used to copy the resource value into the subpart structure. If the name of
a resource in args does not match any of the resources described by resources, then that resource name/value pair in args is silently
ignored.
See XtGetApplicationResources() for a description of the various fields of a XtResource structure and an example of initializing an XtRe-
sourceList.
Usage
If a widget has subpart resources, it can fetch initial values for those resources from the resource database by calling XtGetSubre-
sources() from its initialize() method and passing the user's argument list to override values from the database. In the resource file,
the subpart will have a name, and the subpart resources will be specified under that name in the resource hierarchy. Most widgets will
want to allow the user to set the values of subpart resources from application code as well. One way to do this is to call XtSetSubval-
ues() from within the widget's set_values() method, passing the subpart resource list and the user's argument list. (Prior to Release 4,
you had to use the set_values_hook() method for this purpose.) With this approach, subpart resources seem just like normal widget
resources to the user; both types of resources can be set by calling XtSetValues(). Another approach is to provide a special function
(which will use XtSetSubvalues()) to set values of your subpart. This approach emphasizes that the subpart is a distinct component of the
widget.
Note that a more flexible alternative to subparts is to use non-widget objects which the user can create as children of your widget. This
way the user has a handle on the "subparts" and can manipulate them directly.
To get the values of named resources from a subpart, use XtGetSubvalues().
To set resource values in a subpart structure using a NULL-terminated variable-length argument list instead of an ArgList, use XtVaSetSub-
values().
Structures
XtResource is defined as follows:
typedef struct _XtResource {
String resource_name; /* Resource name */
String resource_class; /* Resource class */
String resource_type; /* Representation type desired */
Cardinal resource_size; /* Size in bytes of representation */
Cardinal resource_offset;/* Offset from base to put resource value */
String default_type; /* Representation type of specified default */
XtPointer default_addr; /* Address of resource default value */
} XtResource, *XtResourceList;
See XtGetApplicationResources() for an explanation of the fields of this structure.
Arg are defined as follows:
typedef struct {
String name;
XtArgVal value;
} Arg, *ArgList;
See Also
XtGetApplicationResources(1), XtGetSubresources(1), XtGetSubvalues(1),
set_values(4).
Xt - Resource Management XtSetSubvalues()