.SH

Module flp

.LP

The flp module loads fl-forms from fd files, as generated

by fdesign. The module is designed to be flexible enough to allow

almost anything to be done with the loaded form.

.LP

Loadform defines 

two types of functions: functions to parse fd files and functions to

create the forms from the templates returned by the parse functions.

There are fairly low-level create functions that create single objects,

and convenience routines that create complete forms, including callbacks,

etc.

.LP

The exception flp.error is raised whenever an error occurs while parsing a forms

definition file or creating a form.

.SH 2

Parsing functions

.LP

There are two parsing functions, parse_form() and parse_forms(). They

take the following form:

.LP

.ft C

ftuple = parse_form(filename, formname)

.br

ftdict = parse_forms(filename)

.IP

Parse_form parses a single form, and returns a tuple (ftmp, otmplist).

Ftmp is a template for a form, otmplist is a list of templates for

objects. See below for a description of these templates.

.IP

Parse_forms parses all forms in an fd file. It returns a dictionary of

(ftmp, otmplist) tuples, indexed by formname.

.IP

Filename is the name of the forms definition file to inspect. The functions

appends '.fd' if needed, and use 'sys.path' to locate the file.

.IP

formname is the name of the form to load. This argument is mandatory,

even if the file only contains one form.

.LP

The form template and object template are structures that contain all

the information read from the fd file, in 'natural' form. A form

template record contains the following fields:

.IP

.nf

"Name", the name of the form;

"Width", the width of the form;

"Height", the height of the form; and

"Numberofobjects", the number of objects in the form.

.LP

An object template contains the following fields:

.IP

.nf

"Class", the class of object (eg. FL.BUTTON);

"Type", the sub-class (eg. FL.NORMALBUTTON);

"Box", a list with four members: [x, y, width, height];

"Boxtype", the type of box (eg. FL.DOWNBOX);

"Colors", a list with the two object colors;

"Alignment", the label alignment (eg. FL.ALIGNLEFT); 

"Style", the label style (eg. FL.BOLDSTYLE);

"Lcol", the label color;

"Label", a string containing the label;

"Name", a string containing the name of the object;

"Callback", a string containing the callback routine name; and

"Argument", a string containing the callback routine extra argument.

.SH

Low-level create routines.

.LP

The three low-level creation routines are called as follows:

.LP

.ft C

form = create_form(form_template)

.IP

Create an fl form from a form template. Returns the form created.

.LP

.ft C

obj = create_object(form, obj_template)

.IP

Create an object in an fl form. Return the new object.

An error is raised if the object has a callback routine.

.SH

High-level create routines.

.LP

The 'standard' way to handle forms in python is to define a class

that contains the form and all the objects (insofar as they are named),

and that defines all the callback functions, and use an instance of

this class to handle the form interaction.

Flp contains three routines that simplify handling this paradigm:

.LP

.ft C

create_full_form(instance, ftuple)

.IP

This routine takes an instance of your form-handling class and an

ftuple (as returned by the parsing routines) as parameters. It inserts

the form into the instance, defines all object names and arranges that

the callback methods are called. All the names inserted into the

instance are the same as the names used for the objects, etc. in the

fd file.

.LP

.ft C

merge_full_form(instance, form, ftuple)

.IP

This function does the same as create_full_form, only it does not create

the form itself nor the 'background box' that fdesign automatically

adds to each form. This is useful if your class inherits a superclass

that already defines a skeleton form (with 'OK' and 'Cancel' buttons,

for instance), and you want to merge the new form into that existing

form. The 'form' parameter is the form to which the new objects are

added.

.LP

If you use the paradigm sketched here but need slightly more control

over object creation there is a routine that creates a single object

and inserts its name (and arranges for the callback routine to be

called):

.LP

.ft C

create_object_instance(instance, form, obj_template)