1Prima::Widget::Link(3)User Contributed Perl DocumentationPrima::Widget::Link(3)
2
6 Prima::Widget::Link - routines for interactive links
7
9 The class can be used in widgets that need to feature links, i e a
10 highlighted rectangle, usually of text. When the user moves mouse or
11 click on a link, depending on the link type, various action can be
12 executed. A "tooltip" link type can display a hint with (rich) text,
13 and a "hyperlink" link can open a browser or pod viewer. The programmer
14 can also customize these actions.
15
17 use Prima qw(Label Application);
18 my $main_window = Prima::MainWindow->new( size => [400, 100] );
20 $main_window->insert( Label =>
21 centered => 1,
22 text => \ "L<tip://$0/ttt|tip>, L<pod://Prima/|podviewer>, L<http://google.com/|browser>, L<id|custom>",
23 onLink => sub { print "$_[2]\n" },
24 );
25 run Prima;
26 =pod
28 =head1 ttt
30 this is a tooltip
32 =for podview <img src="data:base64">
34 R0lGODdhFgAVAIAAAAAAAP///ywAAAAAFgAVAIAAAAD///8CLIyPqcutsKALQKI6qT11R69lWDJm
35 5omm6jqBjucycEx+bVOSNNf1+/NjCREFADs=
36
38 Link types can be set with the url syntax. There are four recognized
39 link types that behave differently.
40 Tooltips
42 These are not really links in the strict sense, as clicking on them
43 doesn't cause any action, however when the user hovers mouse over a
44 tooltip, the module loads the pod content from the url, and displays it
45 as a hint.
46 The idea behind this feature is to collect all tootip cards in a pod
48 section, and referencing them in a text like in the example code in
49 SYNOPSIS above.
50 Syntax: "L<tip://FILEPATH_OR_MODULE/SECTION>" or
52 "L<tip://FILEPATH_OR_MODULE>" where "FILEPATH_OR_MODULE" can refer
53 either to a file (path with slashes/backslashes) or a perl module (with
54 "::"s ).
55 Tooltip text, when selected, is underscored by a dashed line, vs all
57 other link types that draw solid line.
58 Pod sections
60 These links both diplay a pod section preview, like the toolkip, but
61 also open a pod viewer with the referred section when clicked on.
62 Syntax: "L<pod://FILEPATH_OR_MODULE/SECTION>" or
64 "L<pod://FILEPATH_OR_MODULE>" where "FILEPATH_OR_MODULE" can refer
65 either to a file (path with slashes/backslashes) or a perl module (with
66 "::"s ).
67 Hyperlinks
69 Links with schemes "ftp://", "http://", and "https://" open a browser
70 when clicked on.
71 Custom links
73 All other urls, not matched by either scheme above, are expected to be
74 handled programmatically. The preview, if any is handled by the
75 "LinkPreview" event, and click by "Link" event.
76 See Events below.
78
80 Since "Prima::Widget::Link" is not a widget by itself but a collection
81 of routines in a class, an object of such class should be instantiated
82 programmatically and attached to a widget that needs to display links,
83 an owner widget.
84 The owner needs to call mouse and paint methods from inside its
86 "on_mousedown" etc relevant events. The owner might also want to
87 overload link events, see below.
88
90 Prima::Drawable::Markup understands the "L<..|..>" command, which is,
91 unlike perlpod, is formatted with its arguments reversed, to stay
92 consistent with the other markup commands (i e it is
93 "L<http://google.com|search>", not "L<search|http://google.com>" .
94 The simple way to incorporate rich text in both widget and link handler
96 is to use "Prima::Drawable::Markup" to handle the markup parsing, and
97 use the resulting object from the same class both for widget drawing
98 and for the link reactions. One just needs to add " markup ="
99 $markup_object > to " Prima::Widget::Link-"new() >.
100
102 Properties
103 rectangles
104 Contains array of rectangles in arbitrary coordinates that could be
105 used to map screen coordinates to a url. Filled automatically.
106 references
108 An array of URLs
109 Methods
111 add_positions_from_blocks LINK_ID, BLOCKS, %DEFAULTS
112 To be used when the link object is not bound to a markup object and
113 link rectangle recalculation is needed due to formatting change, f
114 ex widget size, font size etc. %DEFAULTS is sent internally to
115 "tb::block_walk" that might need eventual default parameters.
116 Scans BLOCKS and add monotonically increasing LINK_ID to new link
118 rectanges. Return new LINK_ID.
119 clear_positions
121 Clears the content of "rectangles"
122 id2rectangles ID
124 Returns rectangles mapped to a link id. There can be more than 1
125 rectangle bound to a single link ID since link text could be, f ex,
126 wrapped.
127 open_podview URL
129 Opens a pod viewer with the URL
130 open_browser URL
132 Opens a web browser with the URL
133 reset_positions_markup BLOCKS, %DEFAULTS
135 To be used when the link object is bound to a markup object and
136 link rectangle recalculation is needed due to formatting change, f
137 ex widget size, font size etc. %DEFAULTS is sent internally to
138 "tb::block_walk" that might need eventual default parameters.
139 Events
141 All events are send to the owner, not to the link object itself,
142 however the "SELF" parameter is sent and contains the link object.
143 Link SELF, URL, BUTTON, MOD
145 Send to the owner, if any, from within "on_mousedown" event, to
146 indicate that a link as pressed on.
147 LinkPreview SELF, URL_REF
149 Send to the owner, if any, from within "on_mousemove" event. The
150 owner might want to fill URL_REF with (rich) text that will be
151 displayed as a link preview
152 LinkAdjustRect SELF, RECT_REF
154 Since the owner might implement a scrollable view, or any other
155 view that has a coordinate system that is no necessary consistent
156 with the rectangles stored in the link object, this event will be
157 called when a link rectangle needs to be mapped to the owner
158 coordinates.
159
161 Dmitry Karasik, <dmitry@karasik.eu.org>.
162
164 Prima, Prima::Drawable::Markup, Prima::Label, Prima::PodView
165perl v5.36.0 2023-03-20 Prima::Widget::Link(3)