The Fields page describes the detailed "mappings" for each output
field to be generated when the transformation is run. This page is divided
into an upper, middle, and lower section, with adjustable splitter
bars between them. The upper section contains a list of
output fields and mapping information with some pushbuttons
along the top. Below the splitter is a
scrollable text editing box displaying the full mapping
expression for the currently selected output field. The bottom section
contains a grid for viewing and navigating the input table.
Descriptions of
all the controls on the Fields page follow:
- List of Output Fields
- The scrollable list above the splitter bar
displays a row for each output table field that either exists, or for which
there is a non-empty mapping defined in the current configuration. If
an output field exists, its sequence number and attributes (type, width, and
decimal precision) are displayed in the columns after the field name.
When an output field's attributes are blank, it means that this is a
"place-holder" mapping, which has no effect on the running of this
transformation. The mapping expression is displayed in the rightmost
column. If you double-click on a row of the field list, an expression
builder dialog allows you to specify the mapping expression for this output
field. Alternatively, you can view or edit the mapping by using the mapping
editbox below the splitter. When automatic
field-level output display is enabled, the output value is shown as you
move from row to row in the output field list
- Splitter Bars
- You can reapportion the space between the different sections of this
page by dragging the splitters bar between them. Each form
configuration keeps track of its own setting of these splitter positions, i.e.they
are not
a global settings. (This feature is based on the generic SplitCon
classes.)
- Mapping Editbox
- Below the upper splitter, a scrollable text editing
box displays the complete mapping for the currently selected output field in
the list above.
- Input Grid
- Below the lower splitter bar, there is a grid
in the bottom section of the Fields page, by which you can see the input
records and navigate through the input table. When you run a
single-record Test and when output values
are displayed automatically, these operations reflect the results of
applying mapping expressions to the current input record. When automatic
field-level output display is enabled, the output value is shown as you
move from record to record in the input grid.
Across the top of the Fields page is a series of small pushbuttons for sorting the output
field list and resetting the mappings. Note that the order in which
fields are initially listed is not a property of the saved configuration of
XFormDBF, so you must explicitly sort the list to be certain of its current
ordering.
- Field Name
- sorts the list by output field name.
- Seq
- sorts the list by output field sequence number, i.e. the field number in
the output table structure. Note that place-holder mappings have no
sequence number, because these fields are absent from the current output
file.
- Quick Mappings
- automatically supplies trivial mappings for any
output fields that currently have blank mappings, and for which there exists a
correspondingly named input field. I.e. this assigns input fields to
output fields with the same name, but only if no mapping has already been
assigned to those output fields.
- Delete Mapping
- clears the mapping expression for only the currently selected output
field. Note that you can't clear a mapping by double-clicking on its
row in the list and using the expression builder, because a blank expression
is interpreted as "no change" (like Escaping or Cancelling the
dialog).
- Delete All
- clears all of the mapping expressions in the current configuration.
When a "place-holder" mapping (i.e. one for which there exists no
field in the current output table) is cleared, its row is deleted from the
output field list.
Remember that you can always undo any changes you have made to the
mappings (or any other aspect of the form configuration) by using the
Restore pushbutton, which returns the configuration to its last Saved state.
Copyright © 2000 - 2002, SpaceTime Systems