1Tk::ObjScanner(3) User Contributed Perl Documentation Tk::ObjScanner(3)
2
6 Tk::ObjScanner - a GUI to scan any perl data structure or object
7
9 # regular use
10 use Tk::ObjScanner;
11 my $mw = MainWindow->new;
13 my $scanner1 = $mw->ObjScanner(
15 -caller => $object,
16 -title=>"windows"
17 )->pack;
18 my $scanner2 = $mw->ObjScanner(
20 -caller => $object,
21 -title => 'demo setting the scanner options',
22 -background => 'white',
23 -selectbackground => 'beige',
24 -foldImage => $mw->Photo(-file => Tk->findINC('folder.xpm')),
25 -openImage => $mw->Photo(-file => Tk->findINC('openfolder.xpm')),
26 -itemImage => $mw->Photo(-file => Tk->findINC('textfile.xpm')),
27 )->pack( -expand => 1, -fill => 'both' ) ;
28 # non-intrusive scan style
30 # user code to produce data
32 Tk::ObjScanner::scan_object($mydata) ;
33 # resume user code
34
36 The scanner provides a GUI to scan the attributes of an object. It can
37 also be used to scan the elements of a hash or an array.
38 This widget can be used as a regular widget in a Tk application or can
40 be used as an autonomous popup widget that will display the content of
41 a data structure. The latter is like a call to a graphical
42 Data::Dumper. The scanner can be used in an autonomous way with the
43 "scan_object" function.
44 The scanner is a composite widget made of a menubar and Tk::HList.
46 This widget acts as a scanner to the object (or hash ref) passed with
47 the 'caller' parameter. The scanner will retrieve all keys of the
48 hash/object and insert them in the HList.
49 When the user double clicks on a key, the corresponding value will be
51 added in the HList.
52 If the value is a multi-line scalar, the scalar will be displayed in a
54 popup text window. Code ref will be deparsed and shown also in the pop-
55 up window.
56 Tied scalar, hash or array internal can also be scanned by clicking on
58 the middle button to open them.
59 Weak references are recognized (See WeakRef for details)
61
63 scan_object( data )
64 This function is not exported and must be called this way:
65 Tk::ObjScanner::scan_object($data);
67 This function will load Tk and pop up a scanner widget. When the user
69 destroy the widget (with "File -" destroy> menu), the user code is
70 resumed.
71
73 "caller"
74 The ref of the object or hash or array to scan (mandatory). (you
75 can also use '"-caller"')
76 "-title"
78 The title of the menu created by the scanner (optional)
79 "-background"
81 The background color for subwidgets (optional)
82 "-selectbackground"
84 The select background color for HList (optional)
85 "-itemImage"
87 The image for a scalar item (optional, default 'file.xbm')
88 "-foldImage"
90 The image for a composite item (array or hash) when closed
91 (optional, default 'folder.xbm')
92 "-openImage"
94 The image for a composite item (array or hash) when open (optional,
95 default 'openfolder.xbm')
96 "-show_menu"
98 ObjScanner can feature a menu with 'reload' button, 'show tied
99 info', 'view pseudo-hash' check box. (optional default 0).
100 "-destroyable"
102 If set, a menu entry will allow the user to destroy the scanner
103 widget. (optional, default 1) . You may want to set this parameter
104 to 0 if the destroy can be managed by a higher level object. This
105 parameter is ignored if show_menu is unset.
106 "-view_pseudo"
108 If set, will interpret pseudo hashes as hash (default 0). This
109 option is disabled for Perl 5.09 and later.
110 "-show_tied"
112 If set, will indicate if a variable is a tied variable. You can see
113 the internal data of the tied variable by double clicking on the
114 middle button. (default 1)
115
117 updateListBox
118 Update the keys of the listbox. This method may be handy if the scanned
119 object wants to update the listbox of the scanner when the scanned
120 object gets new attributes.
121
123 The name of the widget is misleading as any data (not only object) may
124 be scanned. This widget is in fact a DataScanner.
125 ObjScanner may fail if an object involves a lot of internal perl magic.
127 In this case, I'd be glad to hear about and I'll try to fix the
128 problem.
129 ObjScanner does not detect recursive data structures. It will just keep
131 on displaying the tree until the user gets tired of clicking on the
132 HList items.
133 There's no sure way to detect if a reference is a pseudo-hash or not.
135 When a reference is believed to be a pseudo-hash, ObjScanner will
136 display the content of the reference like a hash. If the reference is
137 should not be displayed like a pseudo-hash, you can turn off the
138 pseudo-hash view with the check button on the top right of the widget.
139 Aynway, pseudo-hashes are deprecated from perl 5.8.0. Hence they are
141 also deprecated in ObjScanner.
142 The icon used for tied scalar changes from scalar icon to folder icon
144 when opening the object hidden behind the tied scalar (using the middle
145 button). I sure could use a better icon for tied items. (hint hint)
146
148 To Rudi Farkas for all the improvements provided to ObjScanner.
149 To Slaven Rezic for:
151 • The propotype code of the pseudo-hash viewer.
153 • The idea to use B::Deparse to view code ref.
155
157 Many thanks to Achim Bohnet for all the tests, patches (and reports) he
158 made. Many improvements were made thanks to his efforts.
159 Thanks to Rudi Farkas for the 'watch' patch.
161 Thanks to Slavec Rezic for the pseudo-hash prototype.
163 Thanks to heytitle for the documentation fixes
165
167 Dominique Dumont, ddumont@cpan.org
168 Copyright (c) 1997-2004,2007,2014,2017 Dominique Dumont. All rights
170 reserved. This program is free software; you can redistribute it
171 and/or modify it under the same terms as Perl itself.
172
174 perl, Tk, Tk::HList, B::Deparse
175perl v5.36.0 2023-01-20 Tk::ObjScanner(3)