1Tk::Canvas::GradientColUosre(r3)Contributed Perl DocumenTtka:t:iCoannvas::GradientColor(3)
2
3
4

NAME

6       Tk::Canvas::GradientColor - To create a Canvas widget with background
7       gradient color.
8

SYNOPSIS

10         #!/usr/bin/perl
11         use strict;
12         use warnings;
13
14         use Tk;
15         use Tk::Canvas::GradientColor;
16
17         my $mw = MainWindow->new(
18           -title      => 'Tk::Canvas::GradientColor',
19           -background => 'white',
20         );
21
22         my $canvas = $mw->GradientColor(
23           -width  => 400,
24           -height => 400,
25         )->pack(qw/ -fill both -expand 1 /);
26
27         $mw->update;
28         sleep 3;
29
30         # Change color
31         $canvas->set_gradientcolor(
32           -start_color => '#000000',
33           -end_color   => '#00CDFF',
34         );
35
36         $mw->update;
37         sleep 3;
38
39         # Change type
40         $canvas->set_gradientcolor(
41           -start       => 50,
42           -end         => 100,
43           -type        => 'mirror_vertical'
44         );
45
46         MainLoop();
47

DESCRIPTION

49       Tk::Canvas::GradientColor is an extension of the Canvas widget. It is
50       an easy way to build a canvas widget with gradient background color.
51

STANDARD OPTIONS

53       -background          -borderwidth        -closeenough
54       -confine -cursor               -height
55       -highlightbackground      -highlightcolor
56       -highlightthickness -insertbackground  -insertborderwidth
57       -insertofftime  -insertontime        -insertwidth       -relief
58       -scrollregion -selectbackground    -selectborderwidth -selectforeground
59       -takefocus -width               -xscrollcommand    -xscrollincrement
60       -yscrollcommand -yscrollincrement
61

WIDGET-SPECIFIC METHODS

63       The Canvas method creates a widget object. This object supports the
64       configure and cget methods described in Tk::options which can be used
65       to enquire and modify the options described above.
66
67   disabled_gradientcolor
68       $canvas_bg->disabled_gradientcolor
69           Disabled background gradient color. The canvas widget will have the
70           background color set by -background option.
71
72             $canvas_bg->disabled_gradientcolor;
73
74   enabled_gradientcolor
75       $canvas_bg->enabled_gradientcolor
76           Enabled background gradient color. Background gradient color is
77           activated by default. Use this method if disabled_gradientcolor
78           method is called.
79
80             $canvas_bg->enabled_gradientcolor;
81
82   get_gradientcolor
83       $canvas_bg->get_gradientcolor
84           Return a hash reference which contains the options to create the
85           background gradient color.
86
87             my $ref_gradient_options = $canvas_bg->get_gradientcolor;
88
89   set_gradientcolor
90       $canvas_bg->set_gradientcolor(?options)
91-type
92
93               8 types are available : linear_horizontal, linear_vertical,
94               mirror_horizontal, mirror_vertical, radial, losange,
95               corner_right and corner_left.
96
97                   -type => 'corner_left',
98
99               Default : linear_horizontal
100
101-start_color
102
103               First color of gradient color.
104
105                   -start_color => 'red',
106
107               Default : #8BC2F5
108
109-end_color
110
111               Last color of gradient color.
112
113                   -end_color => '#FFCD9F',
114
115               Default : white
116
117-start
118
119                   -start => 50, # Must be >= 0, <= 100 and start < end
120
121               Use it for linear_horizontal and linear_vertical type. The
122               first color starts at 'start' percent width of canvas.  The
123               easy way to understand is to test the example in this
124               documentation.
125
126               Ex : width canvas = 1000px, start = 50 : the first part of
127               canvas has the background color of start_color and the gradient
128               color start at 500px.
129
130               Default : 0
131
132               Use it for mirror_horizontal and mirror_vertical type. The
133               first color starts at 'start' percent width of canvas.  The
134               easy way to understand is to test the example in this
135               documentation.
136
137               Ex : width canvas = 1000px, start = 50 : the background
138               gradient color begins at 50 percent in two directions.
139
140               Default : 50
141
142-end
143
144                   -end => 80,  # Must be >= 0, <= 100 and end > start
145
146               Use it for linear_horizontal and linear_vertical type. The last
147               color finishes at 'end' percent width of canvas. The easy way
148               to understand is to test the example in this documentation.
149
150               Default : 100
151
152               Use it for mirror_horizontal and mirror_vertical type. The last
153               color finishes at 'end' percent width of canvas and opposite.
154               The easy way to understand is to test the example in this
155               documentation.
156
157               Default : 100
158
159-number_color
160
161               Number of colors between first and last color to create the
162               gradient.
163
164                   -number_color => 200,
165
166               Default : 100
167
168   rgb_to_hex
169       $canvas_bg->rgb_to_hex($red, $green, $blue)
170           Return hexa code of rgb color.
171
172             my $color = $canvas_bg->rgb_to_hex(200, 102, 65);  # return #C86641
173
174   hex_to_rgb
175       $canvas_bg->hex_to_rgb(string)
176           Return an array with red, green an blue code rgb color.
177
178             my ( $red, $green, $blue ) = $canvas_bg->hex_to_rgb('#C86641');  # return 200, 102, 65
179             my ( $red, $green, $blue ) = $canvas_bg->hex_to_rgb('gray');     # return 190, 190, 190
180

EXAMPLES

182       An example to test the configuration of the widget:
183
184         #!/usr/bin/perl
185         use strict;
186         use warnings;
187
188         use Tk;
189         use Tk::Canvas::GradientColor;
190         use Tk::BrowseEntry;
191
192         my $mw = MainWindow->new(
193           -title      => 'gradient color with canvas',
194           -background => 'snow',
195         );
196
197         my $canvas = $mw->GradientColor(
198           -background => '#005500',
199           -width      => 500,
200           -height     => 500,
201         )->pack(qw/ -fill both -expand 1 /);
202
203         my %arg_gradient = (
204           -type         => undef,
205           -start_color  => '#A780C1',
206           -end_color    => 'white',
207           -start        => undef,
208           -end          => undef,
209           -number_color => undef,
210         );
211
212         # configure start color
213         my $bouton_color1 = $canvas->Button(
214           -text    => 'select color start',
215           -command => sub {
216             $arg_gradient{-start_color} = $canvas->chooseColor( -title => 'select color start' );
217             $canvas->set_gradientcolor(%arg_gradient);
218           },
219         );
220
221         # configure end color
222         my $bouton_color2 = $canvas->Button(
223           -text    => 'select color end',
224           -command => sub {
225             $arg_gradient{-end_color} = $canvas->chooseColor( -title => 'select color end' );
226             $canvas->set_gradientcolor(%arg_gradient);
227           },
228         );
229
230         my $type = $canvas->BrowseEntry(
231           -label   => 'Type gradient color',
232           -choices => [
233             qw/ linear_horizontal linear_vertical mirror_horizontal mirror_vertical radial losange corner_right corner_left/
234           ],
235             -background => 'white',
236           -state              => 'readonly',
237           -disabledbackground => 'yellow',
238           -browsecmd          => sub {
239             my ( $widget, $selection ) = @_;
240             $arg_gradient{-type} = $selection;
241             $canvas->set_gradientcolor(%arg_gradient);
242           },
243         );
244
245         my $start_num = $canvas->Scale(
246           -background   => 'white',
247           -label        => 'Start',
248           -from         => 0,
249           -to           => 100,
250           -variable     => 0,
251           -orient       => 'horizontal',
252           -sliderlength => 10,
253           -command      => sub {
254             my $selection = shift;
255             $arg_gradient{-start} = $selection;
256             $canvas->set_gradientcolor(%arg_gradient);
257           },
258         );
259
260         my $end_num = $canvas->Scale(
261           -background   => 'white',
262           -label        => 'End',
263           -from         => 0,
264           -to           => 100,
265           -variable     => '100',
266           -orient       => 'horizontal',
267           -sliderlength => 10,
268           -command      => sub {
269             my $selection = shift;
270             $arg_gradient{-end} = $selection;
271             $canvas->set_gradientcolor(%arg_gradient);
272           },
273         );
274         my $num                = 100;
275         my $entry_number_color = $canvas->BrowseEntry(
276           -label              => 'Number color',
277           -choices            => [qw/ 2 3 4 5 10 50 100 150 200 250 300 400 500 750 1000 1500 2000 2500/],
278           -state              => 'readonly',
279           -disabledbackground => 'yellow',
280           -background => 'white',
281           -variable           => \$num,
282           -browsecmd          => sub {
283             my ( $widget, $selection ) = @_;
284             $arg_gradient{-number_color} = $selection;
285             $canvas->set_gradientcolor(%arg_gradient);
286           },
287         );
288
289         my $disabled_gradientcolor = $canvas->Button(
290           -text    => 'disabled_gradientcolor',
291           -command => sub { $canvas->disabled_gradientcolor; },
292         );
293         my $enabled_gradientcolor = $canvas->Button(
294           -text    => 'enabled_gradientcolor',
295           -command => sub { $canvas->enabled_gradientcolor; },
296         );
297
298         $canvas->createWindow( 100, 100, -window => $bouton_color1 );
299         $canvas->createWindow( 400, 100, -window => $bouton_color2 );
300         $canvas->createWindow( 100, 150, -window => $start_num );
301         $canvas->createWindow( 100, 200, -window => $end_num );
302         $canvas->createWindow( 350, 150, -window => $entry_number_color );
303         $canvas->createWindow( 350, 200, -window => $type );
304         $canvas->createWindow( 100, 350, -window => $disabled_gradientcolor );
305         $canvas->createWindow( 400, 350, -window => $enabled_gradientcolor );
306
307         MainLoop;
308

AUTHOR

310       Djibril Ousmanou, "<djibel at cpan.org>"
311

BUGS

313       Please report any bugs or feature requests to
314       "bug-Tk-Canvas-GradientColor at rt.cpan.org", or through the web
315       interface at
316       <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Tk-Canvas-GradientColor>.
317       I will be notified, and then you'll automatically be notified of
318       progress on your bug as I make changes.
319

SEE ALSO

321       See Tk::Canvas for details of the standard options.
322

SUPPORT

324       You can find documentation for this module with the perldoc command.
325
326           perldoc Tk::Canvas::GradientColor
327
328       You can also look for information at:
329
330       •   RT: CPAN's request tracker
331
332           <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Tk-Canvas-GradientColor>
333
334       •   AnnoCPAN: Annotated CPAN documentation
335
336           <http://annocpan.org/dist/Tk-Canvas-GradientColor>
337
338       •   CPAN Ratings
339
340           <http://cpanratings.perl.org/d/Tk-Canvas-GradientColor>
341
342       •   Search CPAN
343
344           <http://search.cpan.org/dist/Tk-Canvas-GradientColor/>
345

ACKNOWLEDGEMENTS

348       Copyright 2014 Djibril Ousmanou, all rights reserved.
349
350       This program is free software; you can redistribute it and/or modify it
351       under the same terms as Perl itself.
352
353
354
355perl v5.32.1                      2021-01-27      Tk::Canvas::GradientColor(3)
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