NAME

Prima::Themes - object themes management

DESCRIPTION

Provides a layer for theme registration in Prima. Themes are loosely grouped alternations of default class properties and behaviors, by default stored in thePrima/themes subdirectory. The theme realization is implemented as interception of the object profile during its creation inside::profile_add. Various themes apply various alterations, one way only - once an object is applied to a theme, it cannot be either changed or revoked thereafter.

Theme configuration can be stored in an RC file,~/.prima/themes, and is loaded automatically unless$Prima::Themes::load_rc_file is explicitly set to0 before loading thePrima::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

ThePrima::Themes namespace provides API for the theme registration and execution.Prima::Themes::Proxy is a class for overriding certain methods, for internal realization of a theme.

For the interactive theme selection see theexamples/theme.pl sample program.

SYNOPSIS

# register a theme fileuse Prima::Themes qw(color);# oruse Prima::Themes; load('color');# list registered themesprint Prima::Themes::list;# install a themePrima::Themes::install('cyan');# list installed themesprint Prima::Themes::list_active;# create an object with another theme while 'cyan' is activeClass->new( theme => 'yellow');# remove a themePrima::Themes::uninstall('cyan');

Prima::Themes

load @THEME_MODULES

Loads THEME_MODULES from files via theuse clause, dies on error. Can be used instead of the explicituse call.

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 viaisa to each given class name, and if matched, the $CALLBACK routine is called with the following parameters: object, default profile, user profile, and second item of the matched pair.

If the $CALLBACK isundef, the defaultmerger 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 untilinstall is called. If the $INSTALLER subroutine is passed, it is called during install and uninstall with two parameters, the name of the theme and the boolean install/uninstall flag. When the install flag is 1, the theme is about to be installed; the subroutine is expected to return a boolean success flag. Otherwise, the subroutine's 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 previously loaded and registered THEMES; the installed themes will be applied 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 the keys from $PROFILE_DEFAULT.

load_rc [ $INSTALL = 1 ]

Reads the~/.prima/themes file and loads the listed modules. If $INSTALL = 1, installs the themes from the RC file.

save_rc

Writes configuration of currently installed themes into the RC file, and returns the success flag. If the success flag is 0,$! contains the error.

Prima::Themes::Proxy

An instance ofPrima::Themes::Proxy, created as

Prima::Themes::Proxy-> new( $OBJECT)

that would return a new non-functional wrapper for any Perl object $OBJECT. All methods of the $OBJECT, exceptAUTOLOAD,DESTROY, andnew, are forwarded to the $OBJECT itself transparently. The class can be used, for example, to deny all changes tolineWidth inside the object's painting routine:

package ConstLineWidth;use base '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