PgAccess developer API


Starting with PgAccess 0.98 I am planning to make available a complete API for the PgAccess developers. I plan to make PgAccess not just an administrative tool, but also a tool for easy build of small applications.

That's why PgAccess 0.98 has been internally restructured, every main module of PgAccess has became a namespace (see Tcl namespaces) in order  to hide the variables and internal procedures to the user. Also, all the global variables that have been used before were grouped under a single big associative array called PgAcVar (PgAccess variables) so they should not interfere with user defined global variables.
 
 

Global variables available
 

PgAcVar The main global associative array that hold together various information needed by PgAccess. User should NOT alter it under any circumstances.
CurrentDB The handler of the current opened database. Can be used for database operations as selects or command execution.
Messages The associative array that holds the translation for the current language. Loaded from the appropriate language file from lib/languages directory
PGACCESS_HOME Keep the system directory of PgAccess root installation

 

Window naming convention

Every toplevel window defined by PgAccess has the following naming convention. Every window name starts with .pgaw (PgAccess window) followed by a colon and a name. Example:

.pgaw:User , .pgaw:About , .pgaw:ImportExport
Namespaces available

For every tab from the main database window there is a namespace defined (Tables, Queries, Views, Functions, Sequences, Reports, Forms, Scripts, Users, Schema). Every namespace has by default the following  procedures:

You can use these procedures if you want to produce the same efects as clicking on the desired tab and then on the "New", "Open" or "Design" buttons from the main database window.
Example:
Tables::open "customers"
Queries::open "Invoices received"
Forms::open "Add new invoice"
The Tables::open procedure accepts two optional parameters, filter and order.
Example:
Tables::open "phonebook" "name ~* 'joe'" "age desc"
will open a table view window with predefined filter "name ~* 'joe'" and ordered by descending age.

There is also a special namespace called Database.  Here are some procedures and functions defined for this namespace available to the user:
 
Name Parameters Type Returns Description
vacuum none procedure nothing vacuums the current database
getTablesList none function list returns the list of tables from the current database
executeUpdate sqlcmd function integer execute the sqlcmd command on the current database returning 1 if no errors ocurred or 0 if the command failed

Global functions available
 
Name Parameters Description
setCursor type Set the cursor for all PgAccess windows, type of cursor can be WAIT or CLOCK or WATCH for the hourglass , anything else (or none) to return to the normal cursor shape
parameter msg Shows a modal input dialog with the msg message, wait for user to enter the data and returns it as a string
showError msg Shows a modal dialog window with an error message