# Copyright 2007, 2008, 2009, 2010, 2011, 2012 Kevin Ryde
# This file is part of Gtk2-Ex-WidgetBits.
#
# Gtk2-Ex-WidgetBits is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as published
# by the Free Software Foundation; either version 3, or (at your option) any
# later version.
#
# Gtk2-Ex-WidgetBits is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with Gtk2-Ex-WidgetBits. If not, see <http://www.gnu.org/licenses/>.
package Gtk2::Ex::TreeModelBits;
use 5.008;
use strict;
use warnings;
use Gtk2;
use Exporter;
our @ISA = ('Exporter');
our @EXPORT_OK = qw(column_contents
remove_matching_rows
all_column_types
iter_prev);
our $VERSION = 48;
# uncomment this to run the ### lines
#use Smart::Comments;
sub column_contents {
my ($model, $column) = @_;
my @ret;
# pre-extend, helpful for a list model style, likely to do little for an
# actual tree
$#ret = $model->iter_n_children(undef) - 1;
my $pos = 0;
$model->foreach (sub {
my ($model, $path, $iter) = @_;
$ret[$pos++] = $model->get_value ($iter, $column);
return 0; # keep walking
});
# iterating should give n_children, trim @ret if it doesn't
### assert: $pos >= scalar(@ret)
$#ret = $pos-1;
return @ret;
}
# If a remove() might end up removing more than one row then it's expected
# to leave $iter at whatever next row then exists (at the same depth).
# A multi-remove happens for instance in Gtk2::Ex::ListModelConcat when it's
# presenting two or more copies of one submodel.
# Gtk2::Ex::TreeModelFilter::Change::remove() asks for similar from its
# child remove().
#
sub remove_matching_rows {
my $model = shift;
my $subr = shift;
my @pending;
my $iter = $model->get_iter_first;
for (;;) {
# undef at end of one level, pop to upper level, or finished if no upper
$iter ||= pop @pending || last;
### looking at: $model->get_path($iter)->to_string
if ($subr->($model, $iter, @_)) {
if (! $model->remove ($iter)) {
$iter = undef; # no more at this depth
}
# otherwise $iter updated to next row
next;
}
my $child = $model->iter_children ($iter);
$iter = $model->iter_next ($iter);
if ($child) {
### descend to child: $model->get_path($child)->to_string
push @pending, $iter;
$iter = $child;
}
}
}
sub all_column_types {
my ($model) = @_;
return map { $model->get_column_type($_) } 0 .. $model->get_n_columns - 1;
}
sub iter_prev {
my ($model, $iter) = @_;
my $path = $model->get_path ($iter);
return ($path->prev
? $model->get_iter ($path) # path moved
: undef); # no more nodes (last path index was 0)
}
1;
__END__
=for stopwords TreeModel ListStore Ryde Gtk2 Gtk2-Ex-WidgetBits Perl-Gtk Gtk lookup
=head1 NAME
Gtk2::Ex::TreeModelBits - miscellaneous TreeModel helpers
=head1 SYNOPSIS
use Gtk2::Ex::TreeModelBits;
=head1 FUNCTIONS
=over 4
=item C<@types = Gtk2::Ex::TreeModelBits::all_column_types ($model)>
Return a list of all the column types in C<$model>. For example to create
another ListStore with the same types as an existing one,
my $new_store = Gtk2::ListStore->new
(Gtk2::Ex::TreeModelBits::all_column_types ($old_store));
=item C<@values = Gtk2::Ex::TreeModelBits::column_contents ($model, $col)>
Return a list of all the values in column number C<$col> of a
C<Gtk2::TreeModel> object C<$model>.
Any tree structure in the model is flattened out for the return. A parent
row's column value comes first, followed by the column values from its
children, recursively, as per C<< $model->foreach >>.
=item C<Gtk2::Ex::TreeModelBits::remove_matching_rows ($store, $subr, ...)>
Remove from C<$store> all rows passing C<$subr>. C<$store> can be a
C<Gtk2::TreeStore>, a C<Gtk2::ListStore>, or another type with the same
style C<< $store->remove >> method. C<$subr> is called
$want_remove = &$subr ($store, $iter, ...)
where C<$iter> is the row being considered, and any extra arguments to
C<remove_matching_rows> are passed on to C<$subr>. C<$subr> should return
true if it wants to remove the row.
The order rows are considered and removed is unspecified except that a
parent row is tested before its children, and the children of course are not
tested if the parent is removed.
If you use an old Gtk 2.0.x and might pass a C<Gtk2::ListStore> or
C<Gtk2::TreeStore> to C<remove_matching_rows> then get Perl-Gtk 1.240 or
higher to have the C<remove> method on those classes return a flag the same
as in Gtk 2.2 and up. Otherwise on those stores C<remove_matching_rows>
will stop after the first row removed.
=item C<$iter = Gtk2::Ex::TreeModelBits::iter_prev ($model, $iter)>
Return a new C<Gtk2::TreeIter> which is the row preceding the given
C<$iter>, at the same depth. If C<$iter> is the first element at its depth
then the return is C<undef>.
This is like a reverse of C<iter_next>. Going to the previous row is not a
native operation and might be a touch slow if a model uses say a linked list
and so must chase through data for a path lookup.
=back
=head1 EXPORTS
Nothing is exported by default, but the functions can be requested in usual
C<Exporter> style,
use Gtk2::Ex::TreeModelBits 'remove_matching_rows';
remove_matching_rows ($store, sub { ... });
There's no C<:all> tag since this module is meant as a grab-bag of functions
and to import as-yet unknown things would be asking for name clashes.
=head1 SEE ALSO
L<Gtk2::ListStore>, L<Gtk2::TreeModel>, L<Gtk2::Ex::WidgetBits>,
L<Gtk2::Ex::TreeModel::ImplBits>
=head1 HOME PAGE
L<http://user42.tuxfamily.org/gtk2-ex-widgetbits/index.html>
=head1 LICENSE
Copyright 2007, 2008, 2009, 2010, 2011, 2012 Kevin Ryde
Gtk2-Ex-WidgetBits is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any later
version.
Gtk2-Ex-WidgetBits is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
more details.
You should have received a copy of the GNU General Public License along with
Gtk2-Ex-WidgetBits. If not, see L<http://www.gnu.org/licenses/>.
=cut
