NAME

       Palm::StdAppInfo - Handles standard AppInfo block (categories)

SYNOPSIS

       Usually:

           package MyPDBHandler;
           use Palm::StdAppInfo();             # Note the parentheses

           @ISA = qw( Palm::StdAppInfo );

           use constant APPINFO_PADDING = 1;

           sub ParseAppInfoBlock {
               my $self = shift;
               my $data = shift;
               my $appinfo = {};

               &Palm::StdAppInfo::parse_StdAppInfo($appinfo, $data);

               $app_specific_data = $appinfo->{other};
           }

           sub PackAppInfoBlock {
               my $self = shift;
               my $retval;

               $self->{appinfo}{other} = <pack application-specific data>;
               $retval = &Palm::StdAppInfo::pack_StdAppInfo($self->{appinfo});
               return $retval;
           }

       Or as a standalone "PDB" helper class:

           use Palm::StdAppInfo;

DESCRIPTION

       Many Palm applications use a common format for keeping track of categories.  The "Palm::StdAppInfo" class
       deals with this common format:

               $pdb = new Palm::PDB;
               $pdb->Load("myfile.pdb");

               @categories   = @{$pdb->{appinfo}{categories}};
               $lastUniqueID =   $pdb->{appinfo}{lastUniqueID};
               $other        =   $pdb->{appinfo}{other};

       where:

       @categories is an array of references-to-hash:

       "$cat = $categories[0];"
       "$cat->{name}"
           The name of the category, a string of at most 16 characters.

       "$cat->{id}"
           The  category  ID,  an integer in the range 0-255. Each category has a unique ID. By convention, 0 is
           reserved for the "Unfiled" category; IDs assigned by the  Palm  are  in  the  range  1-127,  and  IDs
           assigned by the desktop are in the range 128-255.

       "$cat->{renamed}"
           A boolean. This field is true iff the category has been renamed since the last sync.

       $lastUniqueID is (I think) the last category ID that was assigned.

       $other  is any data that follows the category list in the AppInfo block. If you're writing a helper class
       for a PDB that includes a category list, you should parse this field to get any  data  that  follows  the
       category   list;   you   should   also  make  sure  that  this  field  is  initialized  before  you  call
       &Palm::StdAppInfo::pack_AppInfo.

   APPINFO_PADDING
       Normally, the AppInfo block includes a byte of padding at the end, to bring its length to an even number.
       However, some databases use this byte for data.

       If your database uses the padding byte for data, then your  &ParseAppInfoBlock  method  (see  "SYNOPSIS")
       should call &parse_StdAppInfo with a true $nopadding argument.

       If, for whatever reason, you wish to inherit &StdAppInfo::ParseAppInfoBlock, then add

           use constant APPINFO_PADDING => 0;

       to your handler package, to tell it that the padding byte is really data.

FUNCTIONS

   seed_StdAppInfo
           &Palm::StdAppInfo::seed_StdAppInfo(\%appinfo);

       Creates  the  standard  fields  in  an existing AppInfo hash. Usually used to ensure that a newly-created
       AppInfo block contains an initialized category array:

               my $appinfo = {};

               &Palm::StdAppInfo::seed_StdAppInfo($appinfo);

       Note: this is not a method.

   newStdAppInfo
           $appinfo = Palm::StdAppInfo->newStdAppInfo;

       Like "seed_StdAppInfo", but creates an AppInfo hash and returns a reference to it.

   new
           $pdb = new Palm::StdAppInfo;

       Create a new PDB, initialized with nothing but a standard AppInfo block.

       There are very few reasons to use this, and even fewer good ones. If you're writing  a  helper  class  to
       parse some PDB format that contains a category list, then you should make that helper class a subclass of
       "Palm::StdAppInfo".

   parse_StdAppInfo
           $len = &Palm::StdAppInfo::parse_StdAppInfo(\%appinfo, $data, $nopadding);

       This  function  (this  is  not  a  method)  is  intended  to  be  called from within a PDB helper class's
       "ParseAppInfoBlock" method.

       "parse_StdAppInfo()" parses a standard AppInfo block from the raw data $data and fills in the  fields  in
       %appinfo. It returns the number of bytes parsed.

       $nopadding is optional, and defaults to false. Normally, the AppInfo block includes a padding byte at the
       end. If $nopadding is true, then &parse_StdAppInfo assumes that the padding byte is application data, and
       includes it in $appinfo{'other'}, so that the caller can parse it.

   ParseAppInfoBlock
           $pdb = new Palm::StdAppInfo;
           $pdb->ParseAppInfoBlock($data);

       If  your  application's AppInfo block contains standard category support and nothing else, you may choose
       to just inherit this method instead of writing your own "ParseAppInfoBlock" method.  Otherwise,  see  the
       example in "SYNOPSIS".

   pack_StdAppInfo
           $data = &Palm::StdAppInfo::pack_StdAppInfo(\%appinfo);

       This  function  (this  is  not  a  method)  is  intended  to  be  called from within a PDB helper class's
       "PackAppInfoBlock" method.

       "pack_StdAppInfo" takes an AppInfo hash and packs it as a string of raw data that can  be  written  to  a
       PDB.

       Note  that  if  you're using this inside a helper class's "PackAppInfoBlock" method, you should make sure
       that $appinfo{other} is properly initialized before you call &Palm::StdAppInfo::pack_StdAppInfo.

       $nopadding is optional, and defaults to false. Normally, the AppInfo block includes a byte of padding  at
       the  end.  If $nopadding is true, then &pack_StdAppInfo doesn't include this byte of padding, so that the
       application can use it.

   PackAppInfoBlock
           $pdb = new Palm::StdAppInfo;
           $data = $pdb->PackAppInfoBlock();

       If your application's AppInfo block contains standard category support and nothing else, you  may  choose
       to  just  inherit  this  method instead of writing your own "PackAppInfoBlock" method. Otherwise, see the
       example in "SYNOPSIS".

   addCategory
           $pdb->addCategory($name [, $id [, $renamed]]);

       Adds a category to $pdb.

       The $name argument specifies the new category's name.

       The optional $id argument specifies the new category's numeric ID; if omitted or undefined,  &addCategory
       will pick one.

       The optional $renamed argument is a boolean value indicating whether the new category should be marked as
       having  been  modified.  This  defaults  to  true  since, conceptually, &addCategory doesn't really add a
       category: it finds one whose name happens to be empty, and renames it.

       Returns  a  true  value  if  successful,  false  otherwise.  In  case  of  failure,   &addCategory   sets
       $Palm::StdAppInfo::error to an error message.

   deleteCategory
           $pdb->deleteCategory($name);

       Deletes  the  category with name $name. Actually, though, it doesn't delete the category: it just changes
       its name to the empty string, and marks the category as renamed.

   renameCategory
           $pdb->renameCategory($oldname, $newname);

       Renames the category named $oldname to $newname.

       If successful, returns a true value. If there is no category named $oldname, returns a  false  value  and
       sets $Palm::StdAppInfo::error to an error message.

SOURCE CONTROL

       The source is in Github:

               http://github.com/briandfoy/p5-Palm/tree/master

AUTHOR

       Alessandro Zummo, "<a.zummo@towertech.it>"

       Currently maintained by brian d foy, "<bdfoy@cpan.org>"

SEE ALSO

       Palm::PDB(3)

perl v5.14.2                                       2010-02-23                                    StdAppInfo(3pm)