Full-View - Windows for Pick

(C) Copyright 1985-1996 Modular Software Corporation. All rights reserved.

Version 2.0 for AP - February 14, 1996

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12: SMART-TREE

FULL-VIEW includes a version of Modular Software's SMART-TREE BTREE system. This version implements all BTREE key updates and retrievals in Pick BASICy code. This implementation is provided primarily for applications compatibility with previous releases of FULL-VIEW.a

A copy of the SMART-TREE manual was included in your FULL-VIEW package. The version of SMART-TREE that is included with FULL-VIEW is referred to as SMART-TREE BASIC in the BTREE manual.

The FULL-VIEW version of SMART-TREE does include two windowing compatible LOOKUP functions which existed in previous versions of FULL-VIEW. These functions are described below.

12.1: LOOKUP AND BROWSE ROUTINES

FULL-VIEW provides two routines which are usually used to access the BTREE key files. These two routines provide an interactive browsing interface which is used to search for a record using the sorted keys. The routines feature:

  1. Forward/backward scrolling along sorted key paths.


  2. Formatted columnar displays. These displays are defined using the key definition utility and can consist of columns containing any data within the data file plus data from other files via the translate conversion functions.


  3. Single key selection of items.


  4. Keyboard look-ahead allowing selection of an item or scrolling of the display forward or backward, even while the screen is still being updated.
FV.LOOKUP( )

This subroutine is used to perform a lookup which allows the user to search for a record using any defined key path. The subroutine can be used anywhere that the user would have been asked to enter the ITEM-ID of the desired record. The format of the subroutine is:

    CALL FV.LOOKUP(file.var,lookup.scr,id,data,error)
file.var
The file variable array which was previously opened with the OPEN BASIC statement.
lookup.scr
Variable to hold lookup screen object definition. Initially null.
id
The ITEM-ID of the selected record.
data
A dynamic array containing the data from the selected record or NULL if this is a new entry.
error
Normally NULL, but may contain the word "ABORT" if the user abandoned the lookup function without making a selection or entering an ITEM-ID.
The FV.LOOKUP routine operates by:

  1. Clearing the screen.


  2. Building a data entry screen with entry fields for the ITEM-ID and for each defined lookup field.


  3. The user enters data into the field desired. If the ITEM-ID field is filled in, then that item will be used without lookups. If another field is filled in, then lookups will proceed from that point along that sorted key.


  4. Pressing [ABORT] will exit the lookup function with a returned status of "ABORT".


  5. The user may interrupt the scrolling screen at any time by making a selection or using one of the control keys. The following control keys are available:
[up]
Scroll back to the previous page.
[left]
Scroll back to the previous page.
[-]
Scroll back to the previous page.
[down]
Scroll forward to the next page
[right]
Scroll forward to the next page
[return]
Scroll forward to the next page
[ABORT]
Return to the lookup screen
  1. If the beginning or end of file is reached, an appropriate message will be displayed and the user will return to step 2.
FV.SCROLL( )

This lookup subroutine has a slightly lower level interface which allows the application program to specify the key in use as well as the starting value. FV.SCROLL can be more versatile than the FV.LOOKUP function but does require more setup from within your applications program. The format of the subroutine is:

    FV.SCROLL(file.var,key.name,key.val,id,data,error)
file.var
the file variable which was previously opened using the OPEN BASIC statement.
key.name
the name of the BTREE key which is to be searched along.
key.var
the beginning value to be searched for.
id
the selected ITEM-ID or NULL if no item is selected.
data
a dynamic array of the data of the selected item, or NULL if no item is selected.
error
normally NULL. The word "ABORT" will be returned if the user exits the lookup function without making a selection.
The FV.SCROLL subroutine functions in the same way as the FV.LOOKUP function with respect to end-user operation. The FV.SCROLL subroutine operates relative to the current window.

12.2: SMART-TREE BASIC WITHOUT FULL-VIEW

The BASIC version of SMART-TREE may be used without activating the windowing software. In order to do this you simply compile your applications with the PC verb with the /C option.


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