################################################################################ # WeBWorK Online Homework Delivery System # Copyright © 2000-2007 The WeBWorK Project, http://openwebwork.sf.net/ # $CVSHeader$ # # This program is free software; you can redistribute it and/or modify it under # the terms of either: (a) the GNU General Public License as published by the # Free Software Foundation; either version 2, or (at your option) any later # version, or (b) the "Artistic License" which comes with this package. # # This program is distributed in the hope that it will be useful, but WITHOUT # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS # FOR A PARTICULAR PURPOSE. See either the GNU General Public License or the # Artistic License for more details. ################################################################################ =head1 NAME Applet.pl - Provides code for inserting FlashApplets and JavaApplets into webwork problems =head1 SYNPOSIS ################################### # Create link to applet ################################### $appletName = "PointGraph"; $applet = FlashApplet( codebase => findAppletCodebase("$appletName.swf"), appletName => $appletName, appletId => $appletName, setStateAlias => 'setXML', getStateAlias => 'getXML', setConfigAlias => 'config', answerBoxAlias => 'answerBox', submitActionScript => qq{ getQE('answerBox').value = getApplet("$appletName").getAnswer() }, ); ################################### # Configure applet ################################### #data to set up the equation $applet->configuration(qq{}); # initial points $applet->intialState(qq{ }); ################################### #insert applet into body ################################### TEXT( MODES(TeX=>'object code', HTML=>$applet->insertAll( includeAnswerBox => 1 debug=>0, reinitialize_button=>1, ))); =head1 DESCRIPTION This file provides an object to store in one place all of the information needed to call an applet. The object FlashApplet has defaults for inserting flash applets. =over =item * =item * =back (not yet completed) The module JavaApplet has defaults for inserting java applets. The module Applet stores common code for the two types of applet. =head1 USAGE These modules are activate by listing it in the modules section of global.conf and rebooting the server. The companion file to this one is macros/AppletObjects.pl qw(Applet FlashApplet JavaApplet) =cut package Applet; use URI::Escape; use MIME::Base64 qw( encode_base64 decode_base64); =head2 Default javaScript functions placed in header =pod These functions are automatically defined for use for any javaScript placed in the text of a PG question. getApplet(appletName) -- finds the applet path in the DOM submitAction() -- calls the submit action of the applets initializeWWquestion() -- calls the initialize action of the applets getQE(name) -- gets an HTML element of the question by name or by id. Be sure to keep all names and ids unique within a given PG question. getQuestionElement(name) -- long form of getQE(name) listQuestionElements() -- for discovering the names of inputs in the PG question. An alert dialog will list all of the elements. Usage: Place this at the END of the question, just before END_DOCUMENT(): TEXT(qq!!); ENDDOCUMENT(); to obtain a list of all of the HTML elements in the question ---------------------------------------------------------------------------- List of accessor methods made available by the FlashApplet class: Usage: $current_value = $applet->method(new_value or empty) These can also be set when creating the class -- for exampe: $applet = new FlashApplet( # can be replaced by $applet =FlashApplet() when using AppletObjects.pl codebase => findAppletCodebase("$appletName.swf"), appletName => $appletName, appletId => $appletName, submitActionAlias => 'checkAnswer', ); appletId for simplicity and reliability appletId and appletName are always the same appletName archive the name of the .jar file containing the applet code code the name of the applet code in the .jar archive codebase a prefix url used to find the archive and the applet itself params an anonymous array containing name/value pairs to configure the applet [name =>'value, ...] width rectangle alloted in the html page for displaying the applet height bgcolor background color of the applet rectangle header stores the text to be added to the header section of the html page object stores the text which places the applet on the html page configuration configuration contains those customizable attributes of the applet which don't change as it is used. When stored in hidden answer fields it is usually stored in base64 encoded format. initialState the state consists of those customizable attributes of the applet which change as the applet is used by the student. It is stored by the calling .pg question so that when revisiting the question the applet will be restored to the same state it was left in when the question was last viewed. getStateAlias (default: getState) alias for command called to read the current state of the applet. The state is passed in plain text xml format with outer tags: .... setStateAlias (default: setState) alias for the command called to reset the state of the applet. The state is passed in plain text in xml format with outer tags: .... configAlias (deprecated) -- a synonym for configAlias getConfigAlias (default: getConfig) -- retrieves the configuration from the applet. This is used mainly for debugging. In principal the configuration remains the same for a given instance of the applet -- i.e. for the homework question for a single student. The state however will change depending on the interactions between the student and the applet. setConfigAlias (default: setConfig ) names the applet command called with the contents of $self->config to configure the applet. The parameters are passed to the applet in plain text using The outer tags must be ..... initializeActionAlias -- (default: initializeAction) the name of the javaScript subroutine called to initialize the applet (some overlap with config/ and setState maxInitializationAttempts -- (default: 5) number attempts to test applet to see if it is installed. If isActive() exists then the WW question waits until the return value is 1 before calling the applet's confguration commands. Because some applets have isActive return 0 even when they are ready, if isActive() exists but does not return 1 then the applet's configuration commands are called after maxInitializationAttempts number of times. If none of the configuration commands of the applet can be detected then the WW question gives up after maxInitializationAttempts. submitActionAlias -- (default: getXML) applet subroutine called when the submit button of the .pg question is pressed. submitActionScript -- (default: qq{ getQE('answerBox').value = getApplet("$appletName").getAnswer() }, answerBoxAlias -- name of answer box to return answer to: default defaultAnswerBox returnFieldName -- (deprecated) synonmym for answerBoxAlias debugMode (default: 0) for debugMode==1 the answerBox and the box preserving the applet state between questions are made visible along with some buttons for manually getting the state of the applet and setting the state of the applet. for debugMode==2, in addition to the answerBox and stateBox there are several alerts which mark progress through the procedures of calling the applet. Useful for troubleshooting where in the chain of command a communication failure occurs Methods: insertHeader -- inserts text in header section of HTML page insertObject -- inserts or tag in body of the HTML page insertAll -- (defined in AppletObjects.pl) installs applet by inserting both header text and the object text Usage: $applet->insertAll( includeAnswerBox => 0, debugMode => 0, reinitialize_button =>0, ); =cut =head4 More details There are three different "images" of the applet. The first is the java or flash applet itself. The object that actually does the work. The second is a perl image of the applet -- henceforth the perlApplet -- which is configured in the .pg file and allows a WeBWorK question to communicate with the applet. The third image is a javaScript image of the applet -- henceforth the jsApplet which is a mirror of the perlApplet but is available to the javaScript code setup and executed in the virtual HTML page defined by the .pg file of the WeBWorK question. One can think of the jsApplet as a runtime version of the perlApplet since it can be accessed and modified after the virtual HTML page has been created by the PG rendering process. The perlApplet is initialized by $newApplet = new flashApplet( appletName=>'myApplet',..... ); The jsApplet is automatically defined in ww_applet_list["myApplet"] by copying the instance variables of $newApplet to a corresponding javaScript object. So $newApplet->{appletName} corresponds to ww_applet_list["myApplet"].appletName. (This paragraph is not yet fully implemented :-(). Currently all messages read by the applet are xml text. If some of the code needs to be printed in the HTML header than it is converted to a base64 constant and then converted back to text form when it is read by a javaScript subroutine. The perlApplet has methods that help place the jsApplet code on the HTML page and create the link to the applet itself. In particular instance variables such as "setStateAlias", "getStateAlias" connect the WW default of "setState" to subroutine name chosen by the applet designer. The aim is to make it easier to connect to applets previously designed to work with javaScript in an HTML page or other systems. The jsApplet acts as an intermediary for commands directed at the applet. It is not necessary for the minimal operations of configuring the applet and maintaining state from one viewing of the WW question to address the applet directly. The methods such as "setState", "getState", "setConfig" which are part of the jsApplet take care of the book keeping details. It is also possible to make direct calls to the applet from handcrafted javaScript subroutines, but it may be convenient to store these as additional methods in the jsApplet. =cut =head4 Detecting that the applet is ready Timing issues are among the pitfalls awaiting when using flash or java applets in WW questions. It is important that the WW question does not issue any commands to the applet until the applet is fully loaded, including the uploading of any additional configuration information from XML files. This can be tricky since the timing issues usually don't arise when initiating the applet from an HTML page. The WW API performs the following actions to determine if the applet is loaded: check the ww_applet_list[appletName].isReady flag (1== applet is ready) -- this caches the readiness information so that it doesn't have to be repeated within a given viewing of a WW question If this is 1 then the applet is ready. determine whether the applet's isActive subroutine is defined AND returns 1 when called. -- if the return value is 1 the applet is ready, if it is zero or no response then the applet is NOT ready -- If the applet has an isActive() subroutine -- there is no alias for this -- then it must return 1 as soon as the applet is ready. Otherwise the applet will timeout. determine whether the applet's setConfig subroutine is defined. -- applet.{setConfigAlias}. determine whether the applet's setState subroutine is defined. determine whether the jsApplets ww_applet_list[appletName].reportsLoaded flag is set to 1 -- this can be set by the applet if it calls the javaScript function "applet_loaded(appletName, loaded_status). The loaded_status is 1 or 0 Logic for determining applet status: if any one of the above checks succeeds (or returns 1) then the applet is consdered to be ready UNLESS the isActive() exists and the call returns a 0 or no response. In this case the applet is assumed to be loading additional data and is not yet ready. For this reason if the isActive subroutine is defined in the applet it must return a 1 once the applet is prepared to accept additional commands. (Since there are some extent flashApplets with non-functioning isActive() subroutines a temporary workaround assuems that after C -- 5 by default -- the applet is in fact ready but the isActive() subroutine is non functioning. This can give rise to false "readiness" signals if the applet takes a long time to load auxiliary files.) The applet itself can take measures to insure that the setConfig subroutine is prepared to respond immediately once the applet is loaded. It can include timers that delay execution of the configuring actions until all of the auxiliary files needed by the applet are loaded. =cut =head4 Instance variables in the javaScript applet ww_applet_list[appletName] Most of the instance variables in the perl version of the applet are transferred to the javaScript applet =cut =head4 Methods defined for the javaScript applet ww_applet_list[appletName] This is not a comprehensive list setConfig -- transmits the information for configuring the applet getConfig -- retrieves the configuration information -- this is used mainly for debugging and may not be defined in most applets setState -- sets the current state (1) from the appletName_state HTML element if this contains an ... string -- if the value contains restart_applet then set the current state to ww_applet_list[appletName].initialState -- if the value is a blank string set the current state to ww_applet_list[appletName].initialState getState -- retrieves the current state and stores in the appletName_state HTML element. =cut =head4 Requirements for applets The following methods are desirable in an applet that preserves state in a WW question. None of them are required. setState(str) (default: setXML) -- set the current state of the applet from an xml string -- should be able to accept an empty string or a string of the form ..... without creating errors -- can be designed to receive other forms of input if it is coordinated with the WW question. getState() (default: getXML) -- return the current state of the applet in an xml string. -- an empty string or a string of the form ..... are the standard responses. -- can be designed to return other strings if it is coordinated with the WW question. setConfig(str) (default: setConfig) -- If the applet allows configuration this configures the applet from an xml string -- should be able to accept an empty string or a string of the form ..... without creating errors -- can be designed to receive other forms of input if it is coordinated with the WW question. getConfig (default: getConfig) -- This returns a string defining the configuration of the applet in an xml string -- an empty string or a string of the form ..... are the standard responses. -- can be designed to return other strings if it is coordinated with the WW question. -- this method is used for debugging to ensure that the configuration was set as expected. getAnswer (default: getAnswer) -- Returns a string (usually NOT xml) which is the response that the student is effectvely submitting to answer the WW question. =cut =head4 Initialization sequence When the WW question is loaded the C javaScript subroutine calls each of the applets used in the question asking them to initialize themselves. The applets initialization method is as follows: -- wait until the applet is loaded and the applet has loaded all of its auxiliary files. -- set the debugMode in the applet -- call the setConfig method in the javaScript applet -- (configuration parameters are "permanent" for the life of the applet -- call the setInitialization method in the javaScript applet -- this often calls the setState method in the applet =cut =head Submit sequence When the WW question submit button is pressed the form containing the WW question calles the javaScript "submitAction()" which then asks each of the applets on the page to perform its submit action which consists of -- if the applet is to be reinitialized (appletName_state contains restart_applet) then the HTML elements appletName_state and previous_appletName_state are set to restart_applet to be interpreted by the next setState command -- Otherwise getState() from the applet and save it to the HTML input element appletName_state -- Perform the javaScript commands in .submitActionScript (default: '' ) a typical submitActionScript looks like getQE(this.answerBox).value = getApplet(appletName).getAnswer() ) =cut sub new { my $class = shift; my $self = { appletName => '', appletId => '', #always use identical applet Id's and applet Names archive => '', code => '', codebase => '', params =>undef, width => 550, height => 400, bgcolor => "#869ca7", configuration => '', # configuration defining the applet initialState => '', # initial state. getStateAlias => 'getXML', setStateAlias => 'setXML', configAlias => '', # deprecated getConfigAlias => 'getConfig', setConfigAlias => 'setConfig', initializeActionAlias => 'setXML', maxInitializationAttempts => 5, # number of attempts to initialize applet submitActionAlias => 'getXML', submitActionScript => '', # script executed on submitting the WW question answerBoxAlias => 'answerBox', answerBox => '', # deprecated returnFieldName => '', # deprecated headerText => DEFAULT_HEADER_TEXT(), objectText => '', debugMode => 0, @_, }; bless $self, $class; $self->initialState(''); if ($self->{returnFieldName} or $self->{answerBox} ) { # backward compatibility warn "use answerBoxAlias instead of returnFieldName or answerBox"; $self->{answerBox}=''; $self->{returnFieldName}=''; } if ($self->{configAlias}) { # backward compatibility warn "use setConfigAlias instead of configAlias"; $self->{configAlias}=''; } $self->configuration(''); return $self; } sub appletId { appletName(@_); } sub appletName { my $self = shift; $self->{appletName} = shift ||$self->{appletName}; # replace the current appletName if non-empty $self->{appletName}; } sub archive { my $self = shift; $self->{archive} = shift ||$self->{archive}; # replace the current archive if non-empty $self->{archive}; } sub code { my $self = shift; $self->{code} = shift ||$self->{code}; # replace the current code if non-empty $self->{code}; } sub codebase { my $self = shift; $self->{codebase} = shift ||$self->{codebase}; # replace the current codebase if non-empty $self->{codebase}; } sub params { my $self = shift; if (ref($_[0]) =~/HASH/) { $self->{params} = shift; } elsif ( !defined($_[0]) or $_[0] =~ '') { # do nothing (read) } else { warn "You must enter a reference to a hash for the parameter list"; } $self->{params}; } sub width { my $self = shift; $self->{width} = shift ||$self->{width}; # replace the current width if non-empty $self->{width}; } sub height { my $self = shift; $self->{height} = shift ||$self->{height}; # replace the current height if non-empty $self->{height}; } sub bgcolor { my $self = shift; $self->{bgcolor} = shift ||$self->{bgcolor}; # replace the current background color if non-empty $self->{bgcolor}; } sub header { my $self = shift; if ($_[0] eq "reset") { # $applet->header('reset'); erases default header text. $self->{headerText}=''; } else { $self->{headerText} .= join("",@_); # $applet->header(new_text); concatenates new_text to existing header. } $self->{headerText}; } sub object { my $self = shift; if ($_[0] eq "reset") { $self->{objectText}=''; } else { $self->{objectText} .= join("",@_); } $self->{objectText}; } sub configuration { my $self = shift; my $str = shift; $self->{configuration} = $str || $self->{configuration}; # replace the current string if non-empty $self->{configuration} =~ s/\n//g; $self->{configuration}; } sub initialState { my $self = shift; my $str = shift; $self->{initialState} = $str ||$self->{initialState}; # replace the current string if non-empty $self->{initialState}; } sub getStateAlias { my $self = shift; $self->{getStateAlias} = shift ||$self->{getStateAlias}; # replace the current contents if non-empty $self->{getStateAlias}; } sub setStateAlias { my $self = shift; $self->{setStateAlias} = shift ||$self->{setStateAlias}; # replace the current contents if non-empty $self->{setStateAlias}; } sub getConfigAlias { my $self = shift; $self->{getConfigAlias} = shift ||$self->{getConfigAlias}; # replace the current contents if non-empty $self->{getConfigAlias}; } sub setConfigAlias { my $self = shift; $self->{setConfigAlias} = shift ||$self->{setConfigAlias}; # replace the current contents if non-empty $self->{setConfigAlias}; } sub initializeActionAlias { my $self = shift; $self->{initializeActionAlias} = shift ||$self->{initializeActionAlias}; # replace the current contents if non-empty $self->{initializeActionAlias}; } sub maxInitializationAttempts { my $self = shift; $self->{maxInitializationAttempts} = shift || $self->{maxInitializationAttempts}; $self->{maxInitializationAttempts}; } sub submitActionAlias { my $self = shift; $self->{submitActionAlias} = shift ||$self->{submitActionAlias}; # replace the current contents if non-empty $self->{submitActionAlias}; } sub submitActionScript { my $self = shift; $self->{submitActionScript} = shift ||$self->{submitActionScript}; # replace the current contents if non-empty $self->{submitActionScript}; } sub answerBoxAlias { my $self = shift; $self->{answerBox} = shift ||$self->{answerBox}; # replace the current contents if non-empty $self->{answerBox}; } sub debugMode { my $self = shift; my $new_flag = shift; $self->{debugMode} = $new_flag if defined($new_flag); $self->{debugMode}; } ####################### # soon to be deprecated? ####################### sub config { my $self = shift; my $str = shift; warn "use $self->configuration instead of $self->config. Internally this string is ascii, not base64 encoded", join(' ', caller()); # $self->{base64_config} = encode_base64($str) || $self->{base64_config}; # replace the current string if non-empty # $self->{base64_config} =~ s/\n//g; # decode_base64($self->{base64_config}); } sub state { my $self = shift; my $str = shift; warn "use $self->initialState instead of $self->state. Internally this string is ascii, not base64 encoded", join(' ', caller()); # $self->{base64_state} = encode_base64($str) ||$self->{base64_state}; # replace the current string if non-empty # $self->{base64_state} =~ s/\n//g; # decode_base64($self->{base64_state}); } sub base64_state{ my $self = shift; warn "use $self->InitialState instead of $self->state. Internally this string is ascii, not base64 encoded", join(' ', caller()); } sub base64_config { my $self = shift; warn "use $self->configuration instead of $self->config. Internally this string is ascii, not base64 encoded"; } sub returnFieldName { my $self = shift; warn "use answerBoxName instead of returnFieldName"; } sub answerBox { my $self = shift; warn "use answerBoxAlias instead of AnswerBox"; } sub configAlias { my $self = shift; warn "use setConfigAlias instead of configAlias"; } ######################### #FIXME # need to be able to adjust header material sub insertHeader { my $self = shift; my $codebase = $self->codebase; my $appletId = $self->appletId; my $appletName = $self->appletName; my $initializeActionAlias = $self->initializeActionAlias; my $submitActionScript = $self->submitActionScript; my $setStateAlias = $self->setStateAlias; my $getStateAlias = $self->getStateAlias; my $setConfigAlias = $self->setConfigAlias; my $getConfigAlias = $self->getConfigAlias; my $maxInitializationAttempts = $self->maxInitializationAttempts; my $debugMode = ($self->debugMode) ? "1": "0"; my $answerBoxAlias = $self->{answerBoxAlias}; my $headerText = $self->header(); #$submitActionScript =~ s/"/\\"/g; # escape quotes for ActionScript # other variables should not have quotes. $submitActionScript =~ s/\n/ /g; # replace returns with spaces -- returns in the wrong spot can cause trouble with javaScript $submitActionScript =~ s/\r/ /g; # replace returns with spaces -- returns can cause trouble my $base64_submitActionScript = encode_base64($submitActionScript); my $base64_configuration = encode_base64($self->configuration); my $base64_initialState = encode_base64($self->initialState); $base64_submitActionScript =~s/\n//g; $base64_initialState =~s/\n//g; # base64 encoded xml $base64_configuration =~s/\n//g; # base64 encoded xml $headerText =~ s/(\$\w+)/$1/gee; # interpolate variables p17 of Cookbook return $headerText; } ######################################################## # HEADER material for one flash or java applet ######################################################## use constant DEFAULT_HEADER_TEXT =><<'END_HEADER_SCRIPT'; END_HEADER_SCRIPT sub insertObject { my $self = shift; my $code = $self->{code}; my $codebase = $self->{codebase}; my $appletId = $self->{appletName}; my $appletName = $self->{appletName}; my $archive = $self->{archive}; my $width = $self->{width}; my $height = $self->{height}; my $applet_bgcolor = $self->{bgcolor}; my $javaParameters = ''; my $flashParameters = ''; my %param_hash = %{$self->params()}; foreach my $key (keys %param_hash) { $javaParameters .= qq!\n!; $flashParameters .= uri_escape($key).'='.uri_escape($param_hash{$key}).'&'; } $flashParameters =~ s/\&$//; # trim last & $objectText = $self->{objectText}; $objectText =~ s/(\$\w+)/$1/gee; return $objectText; } ############################################################################################################### # # FLASH APPLET PACKAGE # ############################################################################################################### package FlashApplet; @ISA = qw(Applet); =head2 Insertion HTML code for FlashApplet =pod The secret to making this applet work with IE in addition to normal browsers is the addition of the C(
) construct just before the object. For some reason IE has trouble locating a flash object which is contained within a form. Adding this second blank form with the larger problemMainForm seems to solve the problem. This follows method2 of the advice given in url(http://kb.adobe.com/selfservice/viewContent.do?externalId=kb400730&sliceId=2) Method1 and methods involving SWFObject(Geoff Stearns) and SWFFormFix (Steve Kamerman) have yet to be fully investigated: http://devel.teratechnologies.net/swfformfix/swfobject_swfformfix_source.js http://www.teratechnologies.net/stevekamerman/index.php?m=01&y=07&entry=entry070101-033933 use constant DEFAULT_OBJECT_TEXT =><<'END_OBJECT_TEXT';
END_OBJECT_TEXT =cut use constant DEFAULT_OBJECT_TEXT =><<'END_OBJECT_TEXT'; END_OBJECT_TEXT sub new { my $class = shift; $class -> SUPER::new( objectText => DEFAULT_OBJECT_TEXT(), @_ ); } ############################################################################################################### # # JAVA APPLET PACKAGE # ############################################################################################################### package JavaApplet; @ISA = qw(Applet); =head2 Insertion HTML code for JavaApplet =pod The secret to making this applet work with IE in addition to normal browsers is the addition of the C(
) construct just before the object. For some reason IE has trouble locating a flash object which is contained within a form. Adding this second blank form with the larger problemMainForm seems to solve the problem. This follows method2 of the advice given in url(http://kb.adobe.com/selfservice/viewContent.do?externalId=kb400730&sliceId=2) Method1 and methods involving SWFObject(Geoff Stearns) and SWFFormFix (Steve Kamerman) have yet to be fully investigated: http://devel.teratechnologies.net/swfformfix/swfobject_swfformfix_source.js http://www.teratechnologies.net/stevekamerman/index.php?m=01&y=07&entry=entry070101-033933 use constant DEFAULT_OBJECT_TEXT =><<'END_OBJECT_TEXT';
$javaParameters END_OBJECT_TEXT =cut use constant DEFAULT_OBJECT_TEXT =><<'END_OBJECT_TEXT'; $javaParameters Sorry, the Applet could not be started. Please make sure that Java 1.4.2 (or later) is installed and activated. (click here to install Java now) END_OBJECT_TEXT sub new { my $class = shift; $class -> SUPER::new( objectText => DEFAULT_OBJECT_TEXT(), @_ ); } ############################################################################################################### # # CANVAS APPLET PACKAGE # ############################################################################################################### package CanvasApplet; @ISA = qw(Applet); =head2 Insertion HTML code for CanvasApplet =pod The secret to making this applet work with IE in addition to normal browsers is the addition of the C(
) construct just before the object. For some reason IE has trouble locating a flash object which is contained within a form. Adding this second blank form with the larger problemMainForm seems to solve the problem. This follows method2 of the advice given in url(http://kb.adobe.com/selfservice/viewContent.do?externalId=kb400730&sliceId=2) Method1 and methods involving SWFObject(Geoff Stearns) and SWFFormFix (Steve Kamerman) have yet to be fully investigated: http://devel.teratechnologies.net/swfformfix/swfobject_swfformfix_source.js http://www.teratechnologies.net/stevekamerman/index.php?m=01&y=07&entry=entry070101-033933 use constant CANVAS_OBJECT_TEXT =><<'END_OBJECT_TEXT';
END_OBJECT_TEXT =cut use constant CANVAS_OBJECT_HEADER_TEXT =><<'END_HEADER_SCRIPT'; END_HEADER_SCRIPT #FIXME need to get rid of hardcoded url use constant CANVAS_OBJECT_TEXT =><<'END_OBJECT_TEXT'; END_OBJECT_TEXT sub new { my $class = shift; $class -> SUPER::new( objectText => CANVAS_OBJECT_TEXT(), headerText => CANVAS_OBJECT_HEADER_TEXT(), @_ ); } 1;