The Config page (an the equivalent Config dialog) contains general information about the current
"configuration" (state) of the form, including where this state-saving
information is stored (the meta-file), the unique configuration id
(functionid),
plus a user-defined category, title, and free-form text
description.
Command buttons are also provided for actions related to state-saving and
restoration. Note that the default behavior upon exiting from the
application is to save the current configuration, unless you deliberately
Abandon this state. A brief explanation of the items on the Config page follows:
- Meta-File
- Specifies the Commander meta-file in which this configuration's state restoration function resides.
The choice of meta-file is determined when XFormDBF is
invoked. There
is no current provision for changing this setting dynamically, although this
capability may be added in the future. It is displayed here purely for
informational purposes.
When you save a configuration, what actually happens is that a
state-restoration function is generated and stored in the meta-file.
The execution of a state restoration function causes the form to be returned
to its prior state. The facilities for state-saving and restoration
are derived from the generic Saver classes.
- FunctionId
- The id of this configuration, which is unique within a given meta-file. This serves as a concise identifier for a particular saved
state. There is no hard limit on the number of different
configurations you can store in a single meta-file. You can't edit the
functionid directly on this page, but you can create a new functionid or
switch to another one via the Switch To... button. (Note that the
special case of a blank functionid disables state-saving and restoration
features.)
- Category
- An optional, user-defined category assigned to this configuration.
This is provided as a way of organizing saved states into logical groupings,
but its usefulness is quite limited in the current implementation.
(Further extensions are planned, for example the ability to filter and sort
the list of saved configurations by category in the Switch To...
dialog.)
- Title
- A brief description of this configuration, which is displayed in the
form's window title. The Switch To... dialog allows you to pick a
saved configuration from a list of their titles.
- Notes Editbox
- Optional free-form comments about the current configuration. You can
scroll through this essentially unlimited length field.
Note that the following command buttons can be configured to appear either on
the Config page or on the main form body, both, or
neither. (The buttons also appear in the equivalent Config dialog
form.) Regardless of
placement, they have the same effect and they logically belong to the Config
page, which is derived from the generic Saver classes.
- Save Config
- Saves the current form configuration (state). The form's state
consists of all the user-supplied parameter settings on every part of the
form, as well as the window position and sizing. The form's state does not
include the contents of any external files or tables that may be referenced
by these settings, only the settings themselves. The saved state
actually is represented as a Commander-based function definition, whose job
is to restore the form to its previous state. This function is
associated with the specified functionid, and it
resides in the meta-file. The Save Config
button is disabled if the functionid is blank. (When you exit
normally from the application, an implicit Save Config is done
automatically unless the functionid is blank or the last action produced an
error, regardless of what actions you
may have taken. You can suppress this automatic state-saving behavior
by using the Abandon button.)
- Restore Config
- Restores the last saved configuration (state) of this form. This is
the converse of the Save Config operation.
Using Restore Config is a convenient, albeit klunky way to undo any kind of
unintentional changes to form settings, but this will not reverse the
effects of any external file or table changes; it only bears on the
state of the form itself. This button is disabled if the functionid
is blank.
- Switch To...
- Invokes a dialog to select a different configuration and switch to it, or
to assign a new unique functionid to the current
configuration. Switching to another configuration does not
automatically save the current one, so remember to do an explicit Save
Config, if necessary, before switching to a different
configuration.
- Copy...
- Similar to the Switch To... command, Copy... picks another
existing configuration to restore into the form, but retains the current functionid. This effectively clones another configuration into the
current one. Note, however, that the meta-file
of saved states is not directly altered by the Copy... command; the
resulting state must be saved either explicitly via Save
Config, or implicitly by exiting from the
application.
- Delete
- Deletes meta-file records (comprising the saved state) for
the current configuration. This has no immediate effect on the form's
appearance, i.e. its current state, except to cause the Delete button to
become disabled, indicating that there no longer exists a saved
"copy" of the current state in the meta-file. If a configuration has not been
saved or its saved state has been deleted, it will not be listed in the Switch
To... dialog.
- Config...
- Launches a resizable dialog for choosing, saving, and restoring previous configurations.
This dialog is a component of the generic Saver facility, essentially
equivalent to the Config page. Sometimes it may be more convenient to
use this separate Saved Configurations dialog, depending on application
design and typical usage patterns.
- Diagnostics...
- Launches a resizable dialog for displaying and setting diagnostics,
tracing, logging, debugging, and error output options. This is the
same dialog that is used to display error and tracing messages when you are
running in diagnostic mode. See ErrHandler
help for more information.
- Abandon
- Exits from the form without saving its present configuration.
Remember that the default behavior upon exiting from a Saver-based
application is to save its current state.
The Abandon button overrides this, forcing the application to exit
immediately without updating the meta-file of saved
states. If you encounter an abnormal error or are in doubt about your
most recent changes, use Abandon to assure preservation of the last clean
saved state.
- OK
- This button is only used in the free-standing Config dialog. It
simply closes the dialog, i.e. it has the same effect as clicking on the
dialog window's close box.
Copyright © 2000 - 2002, SpaceTime Systems