NAME
Prima::Themes - object themes management
DESCRIPTION
Provides layer for theme registration in Prima. Themes are loosely
grouped alternations of default class properties and behavior, by
default stored in "Prima/themes" subdirectory. The theme realization is
implemented as interception of object profile during its creation,
inside "::profile_add". Various themes apply various alterations, one
way only - once an object is applied a theme, it cannot be neither
changed nor revoked thereafter.
Theme configuration can be stored in an rc file, ~/.prima/themes, and
is loaded automatically, unless $Prima::Themes::load_rc_file explicitly
set to 0 before loading the "Prima::Themes" module. In effect, any
Prima application not aware of themes can be coupled with themes in the
rc file by the following:
perl -MPrima::Themes program
"Prima::Themes" namespace provides registration and execution
functionality. "Prima::Themes::Proxy" is a class for overriding
certain methods, for internal realization of a theme.
For interactive theme selection use examples/theme.pl sample program.
SYNOPSIS
# register a theme file
use Prima::Themes qw(color);
# or
use Prima::Themes; load('color');
# list registered themes
print Prima::Themes::list;
# install a theme
Prima::Themes::install('cyan');
# list installed themes
print Prima::Themes::list_active;
# create object with another theme while 'cyan' is active
Class->create( theme => 'yellow');
# remove a theme
Prima::Themes::uninstall('cyan');
Prima::Themes
load @THEME_MODULES
Load THEME_MODULES from files via "use" clause, dies on error. Can
be used instead of explicit "use".
A loaded theme file may register one or more themes.
register $FILE, $THEME, $MATCH, $CALLBACK, $INSTALLER
Registers a previously loaded theme. $THEME is a unique string
identifier. $MATCH is an array of pairs, where the first item is a
class name, and the second is an arbitrary scalar parameter. When a
new object is created, its class is matched via "isa" to each given
class name, and if matched, the $CALLBACK routine is called with
the following parameters: object, default profile, user profile,
second item of the matched pair.
If $CALLBACK is "undef", the default merger routine is called,
which treats the second items of the pairs as hashes of the same
format as the default and user profiles.
The theme is inactive until "install" is called. If $INSTALLER
subroutine is passed, it is called during install and uninstall,
with two parameters, the name of the theme and boolean
install/uninstall flag. When install flag is 1, the theme is about
to be installed; the subroutine is expected to return a boolean
success flag. Otherwise, subroutine return value is not used.
$FILE is used to indicate the file in which the theme is stored.
deregister $THEME
Un-registers $THEME.
install @THEMES
Installs previosuly loaded and registered loaded THEMES; the
installed themes are now used to match new objects.
uninstall @THEMES
Uninstalls loaded THEMES.
list
Returns the list of registered themes.
list_active
Returns the list of installed themes.
loaded $THEME
Return 1 if $THEME is registered, 0 otherwise.
active $THEME
Return 1 if $THEME is installed, 0 otherwise.
select @THEMES
Uninstalls all currently installed themes, and installs THEMES
instead.
merger $OBJECT, $PROFILE_DEFAULT, $PROFILE_USER, $PROFILE_THEME
Default profile merging routine, merges $PROFILE_THEME into
$PROFILE_USER by keys from $PROFILE_DEFAULT.
load_rc [ $INSTALL = 1 ]
Reads data ~/.prima/themes and loads listed modules. If $INSTALL =
1, installs the themes from the rc file.
save_rc
Writes configuration of currently installed themes into rc file,
returns success flag. If success flag is 0, $! contains the error.
Prima::Themes::Proxy
An instance of "Prima::Themes::Proxy", created as
Prima::Themes::Proxy-> new( $OBJECT)
is a non-functional wrapper for any Perl object $OBJECT. All methods of
$OBJECT, except "AUTOLOAD", "DESTROY", and "new", are forwarded to
$OBJECT itself transparently. The class can be used, for example, to
deny all changes to "lineWidth" inside object’s painting routine:
package ConstLineWidth;
use vars qw(@ISA);
@ISA = qw(Prima::Themes::Proxy);
sub lineWidth { 1 } # line width is always 1 now!
Prima::Themes::register( '~/lib/constlinewidth.pm', 'constlinewidth',
[ 'Prima::Widget' => {
onPaint => sub {
my ( $object, $canvas) = @_;
$object-> on_paint( ConstLineWidth-> new( $canvas));
},
} ]
);
AUTHOR
Dmitry Karasik, <dmitry@karasik.eu.org>.
FILES
~/.prima/themes
SEE ALSO
Prima, Prima::Object, examples/themes.pl