NAME
HTML::DragAndDrop - Provides a perl interface for easy use of Walter Zorn's dragdrop Javascript library. See http://www.walterzorn.com/dragdrop/dragdrop_e.htm.
SYNOPSIS
use HTML::DragAndDrop;
my $dd = HTML::DragAndDrop->new(
javascript_dir => '/javascript/',
);
$dd->add_dragable(
name => 'dragable1',
src => '/images/www3.png',
width => 64, height => 64,
);
print $dd->output_html;
print $dd->output_script;
DESCRIPTION
The HTML::DragAndDrop module provides a Perl interface to Walter Zorn's Javascript Drag and Drop library. See http://www.walterzorn.com/dragdrop/dragdrop_e.htm.
Walter's Javascript library provides:
A Cross-browser JavaScript DHTML Library which adds Drag Drop
functionality to layers and to any desired image, even those
integrated into the text flow.
METHODS
new
my $dd = CGI::DragDrop->new(
javascript_dir => '/javascript/',
);
Create a new DragDrop object. The various options are described below:
- javascript_dir
-
Defaults to /. This is the url path to the directory containing wz_dragdrop.js. It can be relative or absolute.
add_dragable
$dd->add_dragable(
name => 'drag1',
width => 120, height => 120,
left => 10, top => 60,
content => $html_to_display,
# or
# src => $image_url,
class => $css_class,
features => $features,
);
This function defines the div tag or image tag that will be dragable. The dragable item must have a name. If your dragable object is an image, then it must also have a width and a height.
- name
-
The name is the HTML id attribute if the dragable object is not an image, otherwise it is the HTML name attribute. It is output in the html tag, and is compulsary for a dragable object.
- width
-
The width (and height) attribute is compulsory for images. It works just like defining the width in the HTML or stylesheet. You must use an absolute value for the width (e.g. 240px) and not a relative value (33%).
- height
-
The height (and width) attribute is compulsory for images. It works just like defining the height in the HTML or stylesheet. You must use an absolute value for the height (e.g. 240px) and not a relative value (33%).
- left
-
Defines how far from the left of edge of the containing object the dragable object will be when the page loads. The containing object is usually the browser window, but could be another html tag, for example a div tag. For those who are stylesheet savvy, this is the left absolute positioning style.
- top
-
Defines how far from the top of edge of the containing object the dragable object will be when the page loads. The containing object is usually the browser window, but could be another html tag, for example a div tag. For those who are stylesheet savvy, this is the top absolute positioning style.
- content
-
If content is provided, the module will create a div tag with an id of the name provided, that contains the content. The content can be straight text or html. If both content and src (image) attributes are present, the src will be used.
- src
-
The source is the url of an image to use. The module generates an IMG tag with a name of the name provided.
- class
-
If a class is specified the dragable object will be created with the class given, otherwise it will have a class of "dragable". This is for use with stylesheets, and is especially handy when using the content attribute.
- features
-
For a complete understanding of the features available, see Walter Zorn's site. The features are passed directly in to the javascript library functions. If you want to use more than one feature, join them in a string with '+' characters. For example: 'RESIZABLE+VERTICAL+CURSOR_HAND', will give you a resizable object, that only moves along the vertical axis, and the mouse cursor displays a hand when hovering over the object. A basic description of the features available is below:
feature applies to description -------- ----------- ------------ CLONE images Makes a single, dragable clone COPY images Makes x dragable copies, e.g. COPY+5 CURSOR_DEFAULT all Default cursor onmouseover CURSOR_CROSSHAIR all Crosshair cursor onmouseover CURSOR_HAND all Hand cursor onmouseover CURSOR_MOVE all Move cursor onmouseover CURSOR_E_RESIZE all East resize cursor onmouseover CURSOR_NE_RESIZE all NorthEast resize cursor onmouseover CURSOR_NW_RESIZE all NorthWest resize cursor onmouseover CURSOR_N_RESIZE all North resize cursor onmouseover CURSOR_SE_RESIZE all SouthEast resize cursor onmouseover CURSOR_SW_RESIZE all SouthWest resize cursor onmouseover CURSOR_W_RESIZE all West resize cursor onmouseover CURSOR_TEXT all Text cursor onmouseover CURSOR_WAIT all Wait cursor onmouseover CURSOR_HELP all Help cursor onmouseover DETACH_CHILDREN layers Dragable objects inside the div don't move with it HORIZONTAL all Only move on the horizontal axis MAXWIDTH all Maximum width to resize to MAXHEIGHT all Maximum height to resize to MINWIDTH all Minimum width to resize to MINHEIGHT all Minimum height to resize to MAXOFFBOTTOM all Maximum downwards movement MAXOFFLEFT all Maximum left movement MAXOFFRIGHT all Maximum right movement MAXOFFTOP all Maximum upwards movement NO_ALT images De-activates the ALT and TITLE attributes NO_DRAG all Object is not dragable RESET_Z all Restores the object's z-index once dropped RESIZABLE all Object can be resized SCALABLE all Object maintains width/height ratio when resized SCROLL all Browser window will scroll as objects are dragged to the edge VERTICAL all Only move on the vertical axis
output_html
The output_html method returns all the html to generate the dragable objects. The output MUST be printed before the output of the output_script method.
output_script
The output_script method returns the javascript needed to make the objects dragable (or have whatever other features you have given them), in a script block. The output of this method MUST be printed after the output of the output_html method.
SEE ALSO
See Walter Zorn's website http://www.walterzorn.com.
And the examples below
EXAMPLES
Example One - An Image
This example shows an image that can be dragged around the browser window.
To run this example, you will need the image script.png in a web-accessible directory called images. (e.g. you should be able to access it as /images/script.png). You will also need Walter Zorn's wz_dragdrop.js in a web-accessible directory called javascript.
#!/usr/bin/perl
use strict;
use warnings;
use CGI;
use HTML::DragAndDrop;
my $q = new CGI;
my $dd = HTML::DragAndDrop->new(
javascript_dir => '/javascript/',
);
$dd->add_dragable(
name => 'dragable1',
src => '/images/script.png',
width => 64, height => 64,
);
print $q->header, $q->start_html;
print $dd->output_html;
print $dd->output_script;
print $q->end_html;
Example Two - Some div tags
This example shows two div tags. On that can be dragged around the browser window and another than can only be dragged a limited distance in the horizontal plane but cannot be dragged vertically.
To run this example you will need Walter Zorn's wz_dragdrop.js in a web-accessible directory called javascript.
#!/usr/bin/perl
use strict;
use warnings;
use CGI;
use CGI::Carp qw(fatalsToBrowser);
use HTML::DragAndDrop;
my $q = new CGI;
my $dd = HTML::DragAndDrop->new(
javascript_dir => '/javascript/',
);
print $q->header;
print $q->start_html(
-title => 'D+D',
-style => {code => '
.dragable {
border: 3pt ridge lightsteelblue;
font-family: verdana, arial, sans-serif;
color: #006;
background: #EEEEEE;
padding: 1em;
font-weight: bold;
}
'}
);
$dd->add_dragable(
name => 'drag1',
width => '120px', height => '120px',
left => '200px', top => '60px',
content => 'Constrained horzontal movement only',
features => 'CURSOR_HAND+HORIZONTAL+MAXOFFLEFT+200+MAXOFFRIGHT+200',
);
$dd->add_dragable(
name => 'drag2',
width => '120px', height => '120px',
left => '300px', top => '200px',
content => 'Any movement allowed',
features => 'CURSOR_HAND',
);
print $dd->output_html;
print $dd->output_script;
print $q->end_html;
AUTHOR
Becky Alcorn, <becky@unisolve.com.au> Simon Taylor, <simon@unisolve.com.au> Unisolve Pty Ltd
COPYRIGHT AND LICENSE
Copyright (C) 2004 by Unisolve Pty Ltd
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.3 or, at your option, any later version of Perl 5 you may have available.
4 POD Errors
The following errors were encountered while parsing the POD:
- Around line 183:
You forgot a '=back' before '=head1'
- Around line 191:
'=item' outside of any '=over'
- Around line 196:
You forgot a '=back' before '=head2'
- Around line 316:
You forgot a '=back' before '=head2'