1Gtk2::Ex::FormFactory::ULsaeyrouCto(n3t)ributed Perl DocGutmke2n:t:aEtxi:o:nFormFactory::Layout(3)
2
6 Gtk2::Ex::FormFactory::Layout - Do layout in a FormFactory framework
7
9 package My::Layout;
10 use base qw/Gtk2::Ex::FormFactory::Layout/;
12 sub build_form { ... }
14 sub add_widget_to_form { ... }
15 ...
16 package main;
18 $ff = Gtk2::Ex::FormFactory->new (
20 layouter => My::Layout->new(),
21 ...
22 );
23
25 This class implements the layout of Containers and their Widgets in a
26 Gtk2::Ex::FormFactory framework. "Layout" means, how are the widgets
27 aligned to each other, how much space is between them, how are titles
28 rendered, how labels, etc.
29 The idea behind Gtk2::Ex::FormFactory::Layout is to have a unique point
31 in a GUI application which actually implements these things. The
32 advantage of this approach is obvious: the implementation is very
33 generic and if you want to change layout things you subclass from
34 Gtk2::Ex::FormFactory::Layout and implement your changes there, and not
35 at hundreds of spots distributed over the source code of your
36 application.
37 The natural result: a consistent looking GUI.
39
41 As described above implementing your own layout module starts with
42 subclassing from Gtk2::Ex::FormFactory::Layout. To use your layout
43 implementation set an object of your class as layouter in your
44 Gtk2::Ex::FormFactory objects.
45 Gtk2::Ex::FormFactory::Layout mainly defines two sorts of methods.
47 BUILD METHODS
49 The names of the methods are derived from the Widget's short names
50 (which can be retrieved with $widget->get_type), with a prepended
51 build_, e.g.:
52 build_form ( ... )
54 build_label ( ... )
55 build_table ( ... )
56 The method prototype looks like this:
58 $layout->build_TYPE ($widget)
60 $widget is the actual Gtk2::Ex::FormFactory::Widget, e.g.
61 Gtk2::Ex::FormFactory::Form for build_form($form).
62 The build_TYPE method actually creates the necessary Gtk2 widgets, e.g.
64 a Gtk2::Table for a Gtk2::Ex::FormFactory::Form and adds these to the
65 FormFactory's widget instance using the set_gtk_widget() and
66 set_gtk_parent_widget() methods of Gtk2::Ex::FormFactory::Widget.
67 Call $widget->set_gtk_widget($gtk_widget) for the primary Gtk2 widget
69 which directly displays the value in question, e.g. a Gtk2::Entry if
70 you're dealing with a Gtk2::Ex::FormFactory::Entry.
71 If you like to do more layout things which require to add the primary
73 Gtk2 widget to a container, e.g. a Gtk2::Frame, you must call
74 $widget->set_gtk_parent_widget($gtk_parent_widget) with the most top
75 level container widget.
76 Note: the implemenations of all the FormFactory's widgets expect a
78 specific gtk_widget to be set. If you like to change the primary Gtk
79 widget you need to create your own Gtk2::Ex::FormFactory::Widget for
80 this, because the default implemention most probably won't work with a
81 another Gtk2::Widget.
82 ADD...TO... METHODS
84 The second type of methods are so called add-to methods, which place a
85 widget inside a container. The prototye is as follows:
86 $layout->add_TYPE_to_TYPE ($widget, $container)
88 $widget is the actual Gtk2::Ex::FormFactory::Widget, e.g.
89 Gtk2::Ex::FormFactory::Form for build_form($form).
90 Examples:
92 add_form_to_window ( ... )
94 add_table_to_form ( ... )
95 This way you can adjust layout at a very detailed level, but you need
97 not. E.g. the implementation of these methods is most likely the same:
98 add_entry_to_form ( ... )
100 add_popup_to_form ( ... )
101 because the implemenation mainly depends on the form (the container
103 widget) and not on the widget which is added to the form.
104 That's why Gtk2::Ex::FormFactory::Layout knows a default mechanism: if
106 no add-to method is found for a specific widget/container pair, a
107 generic default implementation is used instead. These are named as
108 follows:
109 add_widget_to_window ( ... )
111 add_widget_to_form ( ... )
112 add_widget_to_table ( ... )
113 add_widget_to_vbox ( ... )
114 ...
115 For a new Container you just need to implement the generic
117 add_widget_to_TYPE method, and everything will work. If you want to
118 slightly modify the implementation for specific child widgets, you
119 implement only the methods for these and you're done.
120 For a example for such a specific add-to message refer to
122 add_menu_to_window() which attaches the menu without any space around
123 it. The default of a Gtk2::Ex::FormFactory::Window is to have some
124 spacing, which looks ugly around a menu.
125
127 Gtk2::Ex::FormFactory::Layout
128
130 This class has not attributes.
131
133 Jörn Reder <joern at zyn dot de>
134
136 Copyright 2004-2006 by Jörn Reder.
137 This library is free software; you can redistribute it and/or modify it
139 under the terms of the GNU Library General Public License as published
140 by the Free Software Foundation; either version 2.1 of the License, or
141 (at your option) any later version.
142 This library is distributed in the hope that it will be useful, but
144 WITHOUT ANY WARRANTY; without even the implied warranty of
145 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
146 Library General Public License for more details.
147 You should have received a copy of the GNU Library General Public
149 License along with this library; if not, write to the Free Software
150 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307
151 USA.
152
154 Hey! The above document had some coding errors, which are explained
155 below:
156 Around line 1275:
158 Non-ASCII character seen before =encoding in 'Jörn'. Assuming UTF-8
159perl v5.32.1 2021-01-27 Gtk2::Ex::FormFactory::Layout(3)