Annotation of loncom/interface/lonhelper.pm, revision 1.5
1.1 bowersj2 1: # The LearningOnline Network with CAPA
2: # .helper XML handler to implement the LON-CAPA helper
3: #
1.3 bowersj2 4: # $Id: lonhelper.pm,v 1.2 2003/03/21 21:34:56 bowersj2 Exp $
1.1 bowersj2 5: #
6: # Copyright Michigan State University Board of Trustees
7: #
8: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
9: #
10: # LON-CAPA is free software; you can redistribute it and/or modify
11: # it under the terms of the GNU General Public License as published by
12: # the Free Software Foundation; either version 2 of the License, or
13: # (at your option) any later version.
14: #
15: # LON-CAPA is distributed in the hope that it will be useful,
16: # but WITHOUT ANY WARRANTY; without even the implied warranty of
17: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18: # GNU General Public License for more details.
19: #
20: # You should have received a copy of the GNU General Public License
21: # along with LON-CAPA; if not, write to the Free Software
22: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23: #
24: # /home/httpd/html/adm/gpl.txt
25: #
26: # http://www.lon-capa.org/
27: #
28: # (Page Handler
29: #
30: # (.helper handler
31: #
32:
1.5 ! bowersj2 33: # FIXME: Change register calls to register with the helper.
! 34: # Then have the helper reg and unreg the tags.
! 35: # This removes my concerns about breaking other code.
! 36:
1.3 bowersj2 37: =pod
38:
39: =head1 lonhelper - HTML Helper framework for LON-CAPA
40:
41: Helpers, often known as "wizards", are well-established UI widgets that users
42: feel comfortable with. It can take a complicated multidimensional problem the
43: user has and turn it into a series of bite-sized one-dimensional questions.
44:
45: For developers, helpers provide an easy way to bundle little bits of functionality
46: for the user, without having to write the tedious state-maintenence code.
47:
48: Helpers are defined as XML documents, placed in the /home/httpd/html/adm/helpers
49: directory and having the .helper file extension. For examples, see that directory.
50:
51: All classes are in the Apache::lonhelper namespace.
52:
53: =head2 lonhelper XML file format
54:
55: A helper consists of a top-level <helper> tag which contains a series of states.
56: Each state contains one or more state elements, which are what the user sees, like
57: messages, resource selections, or date queries.
58:
59: The helper tag is required to have one attribute, "title", which is the name
60: of the helper itself, such as "Parameter helper".
61:
62: =head2 State tags
63:
64: State tags are required to have an attribute "name", which is the symbolic
65: name of the state and will not be directly seen by the user. The wizard is
66: required to have one state named "START", which is the state the wizard
1.5 ! bowersj2 67: will start with. By convention, this state should clearly describe what
1.3 bowersj2 68: the helper will do for the user, and may also include the first information
69: entry the user needs to do for the helper.
70:
71: State tags are also required to have an attribute "title", which is the
72: human name of the state, and will be displayed as the header on top of
73: the screen for the user.
74:
75: =head2 Example Helper Skeleton
76:
77: An example of the tags so far:
78:
79: <helper title="Example Helper">
80: <state name="START" title="Demonstrating the Example Helper">
81: <!-- notice this is the START state the wizard requires -->
82: </state>
83: <state name="GET_NAME" title="Enter Student Name">
84: </state>
85: </helper>
86:
87: Of course this does nothing. In order for the wizard to do something, it is
88: necessary to put actual elements into the wizard. Documentation for each
89: of these elements follows.
90:
91: =cut
92:
1.1 bowersj2 93: package Apache::lonhelper;
1.2 bowersj2 94: use Apache::Constants qw(:common);
95: use Apache::File;
1.3 bowersj2 96: use Apache::lonxml;
1.2 bowersj2 97:
98: BEGIN {
99: &Apache::lonxml::register('Apache::lonhelper',
1.4 bowersj2 100: ('helper', 'state'));
1.2 bowersj2 101: }
102:
1.3 bowersj2 103: # Since all wizards are only three levels deep (wizard tag, state tag,
104: # substate type), it's easier and more readble to explicitly track
105: # those three things directly, rather then futz with the tag stack
106: # every time.
107: my $helper;
108: my $state;
109: my $substate;
1.4 bowersj2 110: # To collect parameters, the contents of the subtags are collected
111: # into this paramHash, then passed to the element object when the
112: # end of the element tag is located.
113: my $paramHash;
1.2 bowersj2 114:
115: sub handler {
1.3 bowersj2 116: my $r = shift;
1.2 bowersj2 117: $ENV{'request.uri'} = $r->uri();
118: my $filename = '/home/httpd/html' . $r->uri();
119: my $fh = Apache::File->new($filename);
120: my $file;
1.3 bowersj2 121: read $fh, $file, 100000000;
122:
123: Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});
124:
125: # Send header, don't cache this page
126: if ($r->header_only) {
127: if ($ENV{'browser.mathml'}) {
128: $r->content_type('text/xml');
129: } else {
130: $r->content_type('text/html');
131: }
132: $r->send_http_header;
133: return OK;
134: }
135: if ($ENV{'browser.mathml'}) {
136: $r->content_type('text/xml');
137: } else {
138: $r->content_type('text/html');
139: }
140: $r->send_http_header;
141: $r->rflush();
1.2 bowersj2 142:
1.3 bowersj2 143: # Discard result, we just want the objects that get created by the
144: # xml parsing
145: &Apache::lonxml::xmlparse($r, 'helper', $file);
1.2 bowersj2 146:
1.3 bowersj2 147: $r->print($helper->display());
1.2 bowersj2 148: return OK;
149: }
150:
151: sub start_helper {
152: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
153:
154: if ($target ne 'helper') {
155: return '';
156: }
157:
1.3 bowersj2 158: $helper = Apache::lonhelper::helper->new($token->[2]{'title'});
1.4 bowersj2 159: return '';
1.2 bowersj2 160: }
161:
162: sub end_helper {
163: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
164:
1.3 bowersj2 165: if ($target ne 'helper') {
166: return '';
167: }
168:
1.4 bowersj2 169: return '';
1.2 bowersj2 170: }
1.1 bowersj2 171:
1.3 bowersj2 172: sub start_state {
173: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
174:
175: if ($target ne 'helper') {
176: return '';
177: }
178:
179: $state = Apache::lonhelper::state->new($token->[2]{'name'},
180: $token->[2]{'title'});
181: return '';
182: }
183:
184: # don't need this, so ignore it
185: sub end_state {
186: return '';
187: }
188:
1.1 bowersj2 189: 1;
190:
1.3 bowersj2 191: package Apache::lonhelper::helper;
192:
193: use Digest::MD5 qw(md5_hex);
194: use HTML::Entities;
195: use Apache::loncommon;
196: use Apache::File;
197:
198: sub new {
199: my $proto = shift;
200: my $class = ref($proto) || $proto;
201: my $self = {};
202:
203: $self->{TITLE} = shift;
204:
205: # If there is a state from the previous form, use that. If there is no
206: # state, use the start state parameter.
207: if (defined $ENV{"form.CURRENT_STATE"})
208: {
209: $self->{STATE} = $ENV{"form.CURRENT_STATE"};
210: }
211: else
212: {
213: $self->{STATE} = "START";
214: }
215:
216: $self->{TOKEN} = $ENV{'form.TOKEN'};
217: # If a token was passed, we load that in. Otherwise, we need to create a
218: # new storage file
219: # Tried to use standard Tie'd hashes, but you can't seem to take a
220: # reference to a tied hash and write to it. I'd call that a wart.
221: if ($self->{TOKEN}) {
222: # Validate the token before trusting it
223: if ($self->{TOKEN} !~ /^[a-f0-9]{32}$/) {
224: # Not legit. Return nothing and let all hell break loose.
225: # User shouldn't be doing that!
226: return undef;
227: }
228:
229: # Get the hash.
230: $self->{FILENAME} = $Apache::lonnet::tmpdir . md5_hex($self->{TOKEN}); # Note the token is not the literal file
231:
232: my $file = Apache::File->new($self->{FILENAME});
233: my $contents = <$file>;
1.5 ! bowersj2 234:
! 235: # Now load in the contents
! 236: for my $value (split (/&/, $contents)) {
! 237: my ($name, $value) = split(/=/, $value);
! 238: $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
! 239: $self->{VARS}->{$name} = $value;
! 240: }
! 241:
1.3 bowersj2 242: $file->close();
243: } else {
244: # Only valid if we're just starting.
245: if ($self->{STATE} ne 'START') {
246: return undef;
247: }
248: # Must create the storage
249: $self->{TOKEN} = md5_hex($ENV{'user.name'} . $ENV{'user.domain'} .
250: time() . rand());
251: $self->{FILENAME} = $Apache::lonnet::tmpdir . md5_hex($self->{TOKEN});
252: }
253:
254: # OK, we now have our persistent storage.
255:
256: if (defined $ENV{"form.RETURN_PAGE"})
257: {
258: $self->{RETURN_PAGE} = $ENV{"form.RETURN_PAGE"};
259: }
260: else
261: {
262: $self->{RETURN_PAGE} = $ENV{REFERER};
263: }
264:
265: $self->{STATES} = {};
266: $self->{DONE} = 0;
267:
268: bless($self, $class);
269: return $self;
270: }
271:
272: # Private function; returns a string to construct the hidden fields
273: # necessary to have the helper track state.
274: sub _saveVars {
275: my $self = shift;
276: my $result = "";
277: $result .= '<input type="hidden" name="CURRENT_STATE" value="' .
278: HTML::Entities::encode($self->{STATE}) . "\" />\n";
279: $result .= '<input type="hidden" name="TOKEN" value="' .
280: $self->{TOKEN} . "\" />\n";
281: $result .= '<input type="hidden" name="RETURN_PAGE" value="' .
282: HTML::Entities::encode($self->{RETURN_PAGE}) . "\" />\n";
283:
284: return $result;
285: }
286:
287: # Private function: Create the querystring-like representation of the stored
288: # data to write to disk.
289: sub _varsInFile {
290: my $self = shift;
291: my @vars = ();
292: for my $key (keys %{$self->{VARS}}) {
293: push @vars, &Apache::lonnet::escape($key) . '=' .
294: &Apache::lonnet::escape($self->{VARS}->{$key});
295: }
296: return join ('&', @vars);
297: }
298:
1.5 ! bowersj2 299: # Use this to declare variables.
! 300: # FIXME: Document this
! 301: sub declareVar {
! 302: my $self = shift;
! 303: my $var = shift;
! 304:
! 305: if (!defined($self->{VARS}->{$var})) {
! 306: $self->{VARS}->{$var} = '';
! 307: }
! 308:
! 309: my $envname = 'form.' . $var . '.forminput';
! 310: if (defined($ENV{$envname})) {
! 311: $self->{VARS}->{$var} = $ENV{$envname};
! 312: }
! 313: }
! 314:
1.3 bowersj2 315: sub changeState {
316: my $self = shift;
317: $self->{STATE} = shift;
318: }
319:
320: sub registerState {
321: my $self = shift;
322: my $state = shift;
323:
324: my $stateName = $state->name();
325: $self->{STATES}{$stateName} = $state;
326: }
327:
328: # Done in four phases
329: # 1: Do the post processing for the previous state.
330: # 2: Do the preprocessing for the current state.
331: # 3: Check to see if state changed, if so, postprocess current and move to next.
332: # Repeat until state stays stable.
333: # 4: Render the current state to the screen as an HTML page.
334: sub display {
335: my $self = shift;
336:
337: my $result = "";
338:
339: # Phase 1: Post processing for state of previous screen (which is actually
340: # the "current state" in terms of the helper variables), if it wasn't the
341: # beginning state.
342: if ($self->{STATE} ne "START" || $ENV{"form.SUBMIT"} eq "Next ->") {
343: my $prevState = $self->{STATES}{$self->{STATE}};
344: $prevState->postprocess();
345: }
346:
347: # Note, to handle errors in a state's input that a user must correct,
348: # do not transition in the postprocess, and force the user to correct
349: # the error.
350:
351: # Phase 2: Preprocess current state
352: my $startState = $self->{STATE};
353: my $state = $self->{STATES}{$startState};
354:
355: # Error checking; it is intended that the developer will have
356: # checked all paths and the user can't see this!
357: if (!defined($state)) {
358: $result .="Error! The state ". $startState ." is not defined.";
359: return $result;
360: }
361: $state->preprocess();
362:
363: # Phase 3: While the current state is different from the previous state,
364: # keep processing.
365: while ( $startState ne $self->{STATE} )
366: {
367: $startState = $self->{STATE};
368: $state = $self->{STATES}{$startState};
369: $state->preprocess();
370: }
371:
372: # Phase 4: Display.
373: my $stateTitle = $state->title();
374: my $bodytag = &Apache::loncommon::bodytag("$self->{TITLE}",'','');
375:
376: $result .= <<HEADER;
377: <html>
378: <head>
379: <title>LON-CAPA Helper: $self->{TITLE}</title>
380: </head>
381: $bodytag
382: HEADER
383: if (!$state->overrideForm()) { $result.="<form name='wizform' method='GET'>"; }
384: $result .= <<HEADER;
385: <table border="0"><tr><td>
386: <h2><i>$stateTitle</i></h2>
387: HEADER
388:
389: if (!$state->overrideForm()) {
390: $result .= $self->_saveVars();
391: }
392: $result .= $state->render() . "<p> </p>";
393:
394: if (!$state->overrideForm()) {
395: $result .= '<center>';
396: if ($self->{STATE} ne $self->{START_STATE}) {
397: #$result .= '<input name="SUBMIT" type="submit" value="<- Previous" /> ';
398: }
399: if ($self->{DONE}) {
400: my $returnPage = $self->{RETURN_PAGE};
401: $result .= "<a href=\"$returnPage\">End Helper</a>";
402: }
403: else {
404: $result .= '<input name="back" type="button" ';
405: $result .= 'value="<- Previous" onclick="history.go(-1)" /> ';
406: $result .= '<input name="SUBMIT" type="submit" value="Next ->" />';
407: }
408: $result .= "</center>\n";
409: }
410:
1.5 ! bowersj2 411: foreach my $key (keys %{$self->{VARS}}) {
! 412: $result .= "|$key| -> " . $self->{VARS}->{$key} . "<br />";
! 413: }
! 414:
1.3 bowersj2 415: $result .= <<FOOTER;
416: </td>
417: </tr>
418: </table>
419: </form>
420: </body>
421: </html>
422: FOOTER
423:
424: # Handle writing out the vars to the file
425: my $file = Apache::File->new('>'.$self->{FILENAME});
426: print $file $self->_varsInFile();
427:
428: return $result;
429: }
430:
431: 1;
432:
433: package Apache::lonhelper::state;
434:
435: # States bundle things together and are responsible for compositing the
1.4 bowersj2 436: # various elements together. It is not generally necessary for users to
437: # use the state object directly, so it is not perldoc'ed.
438:
439: # Basically, all the states do is pass calls to the elements and aggregate
440: # the results.
1.3 bowersj2 441:
442: sub new {
443: my $proto = shift;
444: my $class = ref($proto) || $proto;
445: my $self = {};
446:
447: $self->{NAME} = shift;
448: $self->{TITLE} = shift;
449: $self->{ELEMENTS} = [];
450:
451: bless($self, $class);
452:
453: $helper->registerState($self);
454:
455: return $self;
456: }
457:
458: sub name {
459: my $self = shift;
460: return $self->{NAME};
461: }
462:
463: sub title {
464: my $self = shift;
465: return $self->{TITLE};
466: }
467:
1.4 bowersj2 468: sub preprocess {
469: my $self = shift;
470: for my $element (@{$self->{ELEMENTS}}) {
471: $element->preprocess();
472: }
473: }
474:
475: sub postprocess {
476: my $self = shift;
477:
478: for my $element (@{$self->{ELEMENTS}}) {
479: $element->postprocess();
480: }
481: }
482:
483: sub overrideForm {
484: return 0;
485: }
486:
487: sub addElement {
488: my $self = shift;
489: my $element = shift;
490:
491: push @{$self->{ELEMENTS}}, $element;
492: }
493:
494: sub render {
495: my $self = shift;
496: my @results = ();
497:
498: for my $element (@{$self->{ELEMENTS}}) {
499: push @results, $element->render();
500: }
501: return join("\n", @results);
502: }
503:
504: 1;
505:
506: package Apache::lonhelper::element;
507: # Support code for elements
508:
509: =pod
510:
511: =head2 Element Base Class
512:
513: The Apache::lonhelper::element base class provides support methods for
514: the elements to use, such as a multiple value processer.
515:
516: B<Methods>:
517:
518: =over 4
519:
520: =item * process_multiple_choices(formName, varName): Process the form
521: element named "formName" and place the selected items into the helper
522: variable named varName. This is for things like checkboxes or
523: multiple-selection listboxes where the user can select more then
524: one entry. The selected entries are delimited by triple pipes in
1.5 ! bowersj2 525: the helper variables, like this:
! 526:
! 527: CHOICE_1|||CHOICE_2|||CHOICE_3
1.4 bowersj2 528:
529: =back
530:
531: =cut
532:
1.5 ! bowersj2 533: BEGIN {
! 534: &Apache::lonxml::register('Apache::lonhelper::element',
! 535: ('nextstate'));
! 536: }
! 537:
1.4 bowersj2 538: # Because we use the param hash, this is often a sufficent
539: # constructor
540: sub new {
541: my $proto = shift;
542: my $class = ref($proto) || $proto;
543: my $self = $paramHash;
544: bless($self, $class);
545:
546: $self->{PARAMS} = $paramHash;
547: $self->{STATE} = $state;
548: $state->addElement($self);
549:
550: # Ensure param hash is not reused
551: $paramHash = {};
552:
553: return $self;
554: }
555:
1.5 ! bowersj2 556: sub start_nextstate {
! 557: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 558:
! 559: if ($target ne 'helper') {
! 560: return '';
! 561: }
! 562:
! 563: $paramHash->{NEXTSTATE} = &Apache::lonxml::get_all_text('/nextstate',
! 564: $parser);
! 565: return '';
! 566: }
! 567:
! 568: sub end_nextstate { return ''; }
! 569:
1.4 bowersj2 570: sub preprocess {
571: return 1;
572: }
573:
574: sub postprocess {
575: return 1;
576: }
577:
578: sub render {
579: return '';
580: }
581:
1.3 bowersj2 582: sub process_multiple_choices {
583: my $self = shift;
584: my $formname = shift;
585: my $var = shift;
586:
587: my $formvalue = $ENV{'form.' . $formname};
588: if ($formvalue) {
1.5 ! bowersj2 589: # Must extract values from querystring directly, as there
1.3 bowersj2 590: # may be more then one.
591: my @values;
1.5 ! bowersj2 592: for my $formparam (split (/&/, $ENV{QUERY_STRING})) {
1.3 bowersj2 593: my ($name, $value) = split(/=/, $formparam);
594: if ($name ne $formname) {
595: next;
596: }
597: $value =~ tr/+/ /;
598: $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
599: push @values, $value;
600: }
1.5 ! bowersj2 601: $helper->{VARS}->{$var} = join('|||', @values);
1.3 bowersj2 602: }
603:
604: return;
605: }
606:
1.4 bowersj2 607: 1;
608:
609: package Apache::lonhelper::message;
610:
611: =pod
612:
613: =head2 Element: message
614:
615: Message elements display the contents of their <message_text> tags, and
1.5 ! bowersj2 616: transition directly to the state in the <nextstate> tag. Example:
1.4 bowersj2 617:
618: <message>
1.5 ! bowersj2 619: <nextstate>GET_NAME</nextstate>
1.4 bowersj2 620: <message_text>This is the <b>message</b> the user will see,
621: <i>HTML allowed</i>.</message_text>
622: </message>
623:
1.5 ! bowersj2 624: This will display the HTML message and transition to the <nextstate> if
1.4 bowersj2 625: given. The HTML will be directly inserted into the wizard, so if you don't
626: want text to run together, you'll need to manually wrap the <message_text>
627: in <p> tags, or whatever is appropriate for your HTML.
628:
1.5 ! bowersj2 629: Message tags do not add in whitespace, so if you want it, you'll need to add
! 630: it into states. This is done so you can inline some elements, such as
! 631: the <date> element, right between two messages, giving the appearence that
! 632: the <date> element appears inline. (Note the elements can not be embedded
! 633: within each other.)
! 634:
1.4 bowersj2 635: This is also a good template for creating your own new states, as it has
636: very little code beyond the state template.
637:
638: =cut
639:
640: no strict;
641: @ISA = ("Apache::lonhelper::element");
642: use strict;
643:
644: BEGIN {
645: &Apache::lonxml::register('Apache::lonhelper::message',
1.5 ! bowersj2 646: ('message', 'message_text'));
1.3 bowersj2 647: }
648:
1.5 ! bowersj2 649: sub new {
! 650: my $ref = Apache::lonhelper::element->new();
! 651: bless($ref);
! 652: }
1.4 bowersj2 653:
654: # CONSTRUCTION: Construct the message element from the XML
655: sub start_message {
656: return '';
1.3 bowersj2 657: }
658:
1.4 bowersj2 659: sub end_message {
660: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
661:
662: if ($target ne 'helper') {
663: return '';
664: }
665: Apache::lonhelper::message->new();
666: return '';
1.3 bowersj2 667: }
668:
1.5 ! bowersj2 669: sub start_message_text {
1.4 bowersj2 670: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
671:
672: if ($target ne 'helper') {
673: return '';
674: }
1.5 ! bowersj2 675:
! 676: $paramHash->{MESSAGE_TEXT} = &Apache::lonxml::get_all_text('/message_text',
! 677: $parser);
! 678: }
1.3 bowersj2 679:
1.5 ! bowersj2 680: sub end_message_text { return 1; }
! 681:
! 682: sub render {
! 683: my $self = shift;
! 684:
! 685: return $self->{MESSAGE_TEXT};
! 686: }
! 687: # If a NEXTSTATE was given, switch to it
! 688: sub postprocess {
! 689: my $self = shift;
! 690: if (defined($self->{NEXTSTATE})) {
! 691: $helper->changeState($self->{NEXTSTATE});
! 692: }
! 693: }
! 694: 1;
! 695:
! 696: package Apache::lonhelper::choices;
! 697:
! 698: =pod
! 699:
! 700: =head2 Element: choices
! 701:
! 702: Choice states provide a single choice to the user as a text selection box.
! 703: A "choice" is two pieces of text, one which will be displayed to the user
! 704: (the "human" value), and one which will be passed back to the program
! 705: (the "computer" value). For instance, a human may choose from a list of
! 706: resources on disk by title, while your program wants the file name.
! 707:
! 708: <choices> takes an attribute "variable" to control which helper variable
! 709: the result is stored in.
! 710:
! 711: <choices> takes an attribute "multichoice" which, if set to a true
! 712: value, will allow the user to select multiple choices.
! 713:
! 714: B<SUB-TAGS>
! 715:
! 716: <choices> can have the following subtags:
! 717:
! 718: =over 4
! 719:
! 720: =item * <nextstate>state_name</nextstate>: If given, this will cause the
! 721: choice element to transition to the given state after executing. If
! 722: this is used, do not pass nextstates to the <choice> tag.
! 723:
! 724: =item * <choice />: If the choices are static,
! 725: this element will allow you to specify them. Each choice
! 726: contains attribute, "computer", as described above. The
! 727: content of the tag will be used as the human label.
! 728: For example,
! 729: <choice computer='234-12-7312'>Bobby McDormik</choice>.
! 730:
! 731: <choice> may optionally contain a 'nextstate' attribute, which
! 732: will be the state transisitoned to if the choice is made, if
! 733: the choice is not multichoice.
! 734:
! 735: =back
! 736:
! 737: To create the choices programmatically, either wrap the choices in
! 738: <condition> tags (prefered), or use an <exec> block inside the <choice>
! 739: tag. Store the choices in $state->{CHOICES}, which is a list of list
! 740: references, where each list has three strings. The first is the human
! 741: name, the second is the computer name. and the third is the option
! 742: next state. For example:
! 743:
! 744: <exec>
! 745: for (my $i = 65; $i < 65 + 26; $i++) {
! 746: push @{$state->{CHOICES}}, [chr($i), $i, 'next'];
! 747: }
! 748: </exec>
! 749:
! 750: This will allow the user to select from the letters A-Z (in ASCII), while
! 751: passing the ASCII value back into the helper variables, and the state
! 752: will in all cases transition to 'next'.
! 753:
! 754: You can mix and match methods of creating choices, as long as you always
! 755: "push" onto the choice list, rather then wiping it out. (You can even
! 756: remove choices programmatically, but that would probably be bad form.)
! 757:
! 758: FIXME: Document and implement <exec> and <condition> in the element package.
! 759:
! 760: =cut
! 761:
! 762: no strict;
! 763: @ISA = ("Apache::lonhelper::element");
! 764: use strict;
! 765:
! 766: BEGIN {
! 767: &Apache::lonxml::register('Apache::lonhelper::choices',
! 768: ('choice', 'choices'));
! 769: }
! 770:
! 771: sub new {
! 772: my $ref = Apache::lonhelper::element->new();
! 773: bless($ref);
! 774: }
! 775:
! 776: # CONSTRUCTION: Construct the message element from the XML
! 777: sub start_choices {
! 778: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 779:
! 780: if ($target ne 'helper') {
! 781: return '';
! 782: }
! 783:
! 784: # Need to initialize the choices list, so everything can assume it exists
! 785: $paramHash->{'variable'} = $token->[2]{'variable'};
! 786: $helper->declareVar($paramHash->{'variable'});
! 787: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
! 788: $paramHash->{CHOICES} = [];
! 789: return '';
! 790: }
! 791:
! 792: sub end_choices {
! 793: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 794:
! 795: if ($target ne 'helper') {
! 796: return '';
! 797: }
! 798: Apache::lonhelper::choices->new();
! 799: return '';
! 800: }
! 801:
! 802: sub start_choice {
! 803: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 804:
! 805: if ($target ne 'helper') {
! 806: return '';
! 807: }
! 808:
! 809: my $computer = $token->[2]{'computer'};
! 810: my $human = &Apache::lonxml::get_all_text('/choice',
! 811: $parser);
! 812: my $nextstate = $token->[2]{'nextstate'};
! 813: push @{$paramHash->{CHOICES}}, [$human, $computer, $nextstate];
! 814: return '';
! 815: }
! 816:
! 817: sub end_choice {
! 818: return '';
! 819: }
! 820:
! 821: sub render {
! 822: # START HERE: Replace this with correct choices code.
! 823: my $self = shift;
! 824: my $var = $self->{'variable'};
! 825: my $buttons = '';
! 826: my $result = '';
! 827:
! 828: if ($self->{'multichoice'}) {
! 829: $result = <<SCRIPT;
! 830: <script>
! 831: function checkall(value) {
! 832: for (i=0; i<document.forms.wizform.elements.length; i++) {
! 833: document.forms.wizform.elements[i].checked=value;
! 834: }
! 835: }
! 836: </script>
! 837: SCRIPT
! 838: $buttons = <<BUTTONS;
! 839: <br />
! 840: <input type="button" onclick="checkall(true)" value="Select All" />
! 841: <input type="button" onclick="checkall(false)" value="Unselect All" />
! 842: <br />
! 843: BUTTONS
! 844: }
! 845:
! 846: if (defined $self->{ERROR_MSG}) {
! 847: $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
! 848: }
! 849:
! 850: $result .= $buttons;
! 851:
! 852: $result .= "<table>\n\n";
! 853:
! 854: my $type = "radio";
! 855: if ($self->{'multichoice'}) { $type = 'checkbox'; }
! 856: my $checked = 0;
! 857: foreach my $choice (@{$self->{CHOICES}}) {
! 858: $result .= "<tr>\n<td width='20'> </td>\n";
! 859: $result .= "<td valign='top'><input type='$type' name='$var.forminput'"
! 860: . "' value='" .
! 861: HTML::Entities::encode($choice->[1])
! 862: . "'";
! 863: if (!$self->{'multichoice'} && !$checked) {
! 864: $result .= " checked ";
! 865: $checked = 1;
! 866: }
! 867: $result .= "/></td><td> " . $choice->[0] . "</td></tr>\n";
! 868: }
! 869: $result .= "</table>\n\n\n";
! 870: $result .= $buttons;
! 871:
! 872: return $result;
! 873: }
! 874:
! 875: # If a NEXTSTATE was given or a nextstate for this choice was
! 876: # given, switch to it
! 877: sub postprocess {
! 878: my $self = shift;
! 879: my $chosenValue = $ENV{'form.' . $self->{'variable'} . '.forminput'};
! 880:
! 881: if (defined($self->{NEXTSTATE})) {
! 882: $helper->changeState($self->{NEXTSTATE});
! 883: }
! 884:
! 885: foreach my $choice (@{$self->{CHOICES}}) {
! 886: if ($choice->[1] eq $chosenValue) {
! 887: if (defined($choice->[2])) {
! 888: $helper->changeState($choice->[2]);
! 889: }
! 890: }
! 891: }
! 892: }
! 893: 1;
! 894:
! 895: package Apache::lonhelper::date;
! 896:
! 897: =pod
! 898:
! 899: =head2 Element: date
! 900:
! 901: Date elements allow the selection of a date with a drop down list.
! 902:
! 903: Date elements can take two attributes:
! 904:
! 905: =over 4
! 906:
! 907: =item * B<variable>: The name of the variable to store the chosen
! 908: date in. Required.
! 909:
! 910: =item * B<hoursminutes>: If a true value, the date will show hours
! 911: and minutes, as well as month/day/year. If false or missing,
! 912: the date will only show the month, day, and year.
! 913:
! 914: =back
! 915:
! 916: Date elements contain only an option <nextstate> tag to determine
! 917: the next state.
! 918:
! 919: Example:
! 920:
! 921: <date variable="DUE_DATE" hoursminutes="1">
! 922: <nextstate>choose_why</nextstate>
! 923: </date>
! 924:
! 925: =cut
! 926:
! 927: no strict;
! 928: @ISA = ("Apache::lonhelper::element");
! 929: use strict;
! 930:
! 931: use Time::localtime;
! 932:
! 933: BEGIN {
! 934: &Apache::lonxml::register('Apache::lonhelper::date',
! 935: ('date'));
! 936: }
! 937:
! 938: # Don't need to override the "new" from element
! 939: sub new {
! 940: my $ref = Apache::lonhelper::element->new();
! 941: bless($ref);
! 942: }
! 943:
! 944: my @months = ("January", "February", "March", "April", "May", "June", "July",
! 945: "August", "September", "October", "November", "December");
! 946:
! 947: # CONSTRUCTION: Construct the message element from the XML
! 948: sub start_date {
! 949: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 950:
! 951: if ($target ne 'helper') {
! 952: return '';
! 953: }
! 954:
! 955: $paramHash->{'variable'} = $token->[2]{'variable'};
! 956: $helper->declareVar($paramHash->{'variable'});
! 957: $paramHash->{'hoursminutes'} = $token->[2]{'hoursminutes'};
! 958: }
! 959:
! 960: sub end_date {
! 961: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 962:
! 963: if ($target ne 'helper') {
! 964: return '';
! 965: }
! 966: Apache::lonhelper::date->new();
! 967: return '';
! 968: }
! 969:
! 970: sub render {
! 971: my $self = shift;
! 972: my $result = "";
! 973: my $var = $self->{'variable'};
! 974:
! 975: my $date;
! 976:
! 977: # Default date: The current hour.
! 978: $date = localtime();
! 979: $date->min(0);
! 980:
! 981: if (defined $self->{ERROR_MSG}) {
! 982: $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
! 983: }
! 984:
! 985: # Month
! 986: my $i;
! 987: $result .= "<select name='${var}month'>\n";
! 988: for ($i = 0; $i < 12; $i++) {
! 989: if ($i == $date->mon) {
! 990: $result .= "<option value='$i' selected>";
! 991: } else {
! 992: $result .= "<option value='$i'>";
! 993: }
! 994: $result .= $months[$i] . "</option>\n";
! 995: }
! 996: $result .= "</select>\n";
! 997:
! 998: # Day
! 999: $result .= "<select name='${var}day'>\n";
! 1000: for ($i = 1; $i < 32; $i++) {
! 1001: if ($i == $date->mday) {
! 1002: $result .= '<option selected>';
! 1003: } else {
! 1004: $result .= '<option>';
! 1005: }
! 1006: $result .= "$i</option>\n";
! 1007: }
! 1008: $result .= "</select>,\n";
! 1009:
! 1010: # Year
! 1011: $result .= "<select name='${var}year'>\n";
! 1012: for ($i = 2000; $i < 2030; $i++) { # update this after 64-bit dates
! 1013: if ($date->year + 1900 == $i) {
! 1014: $result .= "<option selected>";
! 1015: } else {
! 1016: $result .= "<option>";
! 1017: }
! 1018: $result .= "$i</option>\n";
! 1019: }
! 1020: $result .= "</select>,\n";
! 1021:
! 1022: # Display Hours and Minutes if they are called for
! 1023: if ($self->{'hoursminutes'}) {
! 1024: # Build hour
! 1025: $result .= "<select name='${var}hour'>\n";
! 1026: $result .= "<option " . ($date->hour == 0 ? 'selected ':'') .
! 1027: " value='0'>midnight</option>\n";
! 1028: for ($i = 1; $i < 12; $i++) {
! 1029: if ($date->hour == $i) {
! 1030: $result .= "<option selected value='$i'>$i a.m.</option>\n";
! 1031: } else {
! 1032: $result .= "<option value='$i'>$i a.m</option>\n";
! 1033: }
! 1034: }
! 1035: $result .= "<option " . ($date->hour == 12 ? 'selected ':'') .
! 1036: " value='12'>noon</option>\n";
! 1037: for ($i = 13; $i < 24; $i++) {
! 1038: my $printedHour = $i - 12;
! 1039: if ($date->hour == $i) {
! 1040: $result .= "<option selected value='$i'>$printedHour p.m.</option>\n";
! 1041: } else {
! 1042: $result .= "<option value='$i'>$printedHour p.m.</option>\n";
! 1043: }
! 1044: }
! 1045:
! 1046: $result .= "</select> :\n";
! 1047:
! 1048: $result .= "<select name='${var}minute'>\n";
! 1049: for ($i = 0; $i < 60; $i++) {
! 1050: my $printedMinute = $i;
! 1051: if ($i < 10) {
! 1052: $printedMinute = "0" . $printedMinute;
! 1053: }
! 1054: if ($date->min == $i) {
! 1055: $result .= "<option selected>";
! 1056: } else {
! 1057: $result .= "<option>";
! 1058: }
! 1059: $result .= "$printedMinute</option>\n";
! 1060: }
! 1061: $result .= "</select>\n";
! 1062: }
! 1063:
! 1064: return $result;
! 1065:
! 1066: }
! 1067: # If a NEXTSTATE was given, switch to it
! 1068: sub postprocess {
! 1069: my $self = shift;
! 1070: my $var = $self->{'variable'};
! 1071: my $month = $ENV{'form.' . $var . 'month'};
! 1072: my $day = $ENV{'form.' . $var . 'day'};
! 1073: my $year = $ENV{'form.' . $var . 'year'};
! 1074: my $min = 0;
! 1075: my $hour = 0;
! 1076: if ($self->{'hoursminutes'}) {
! 1077: $min = $ENV{'form.' . $var . 'minute'};
! 1078: $hour = $ENV{'form.' . $var . 'hour'};
! 1079: }
! 1080:
! 1081: my $chosenDate = Time::Local::timelocal(0, $min, $hour, $day, $month, $year);
! 1082: # Check to make sure that the date was not automatically co-erced into a
! 1083: # valid date, as we want to flag that as an error
! 1084: # This happens for "Feb. 31", for instance, which is coerced to March 2 or
! 1085: # 3, depending on if it's a leapyear
! 1086: my $checkDate = localtime($chosenDate);
! 1087:
! 1088: if ($checkDate->mon != $month || $checkDate->mday != $day ||
! 1089: $checkDate->year + 1900 != $year) {
! 1090: $self->{ERROR_MSG} = "Can't use " . $months[$month] . " $day, $year as a "
! 1091: . "date because it doesn't exist. Please enter a valid date.";
! 1092: return;
! 1093: }
! 1094:
! 1095: $helper->{VARS}->{$var} = $chosenDate;
! 1096:
! 1097: if (defined($self->{NEXTSTATE})) {
! 1098: $helper->changeState($self->{NEXTSTATE});
! 1099: }
! 1100: }
! 1101: 1;
! 1102:
! 1103: package Apache::lonhelper::resource;
! 1104:
! 1105: =pod
! 1106:
! 1107: =head2 Element: resource
! 1108:
! 1109: <resource> elements allow the user to select one or multiple resources
! 1110: from the current course. You can filter out which resources they can view,
! 1111: and filter out which resources they can select. The course will always
! 1112: be displayed fully expanded, because of the difficulty of maintaining
! 1113: selections across folder openings and closings. If this is fixed, then
! 1114: the user can manipulate the folders.
! 1115:
! 1116: <resource> takes the standard variable attribute to control what helper
! 1117: variable stores the results. It also takes a "multichoice" attribute,
! 1118: which controls whether the user can select more then one resource.
! 1119:
! 1120: B<SUB-TAGS>
! 1121:
! 1122: =over 4
! 1123:
! 1124: =item * <filterfunc>: If you want to filter what resources are displayed
! 1125: to the user, use a filter func. The <filterfunc> tag should contain
! 1126: Perl code that when wrapped with "sub { my $res = shift; " and "}" is
! 1127: a function that returns true if the resource should be displayed,
! 1128: and false if it should be skipped. $res is a resource object.
! 1129: (See Apache::lonnavmaps documentation for information about the
! 1130: resource object.)
! 1131:
! 1132: =item * <choicefunc>: Same as <filterfunc>, except that controls whether
! 1133: the given resource can be chosen. (It is almost always a good idea to
! 1134: show the user the folders, for instance, but you do not always want to
! 1135: let the user select them.)
! 1136:
! 1137: =item * <nextstate>: Standard nextstate behavior.
! 1138:
! 1139: =item * <valuefunc>: This function controls what is returned by the resource
! 1140: when the user selects it. Like filterfunc and choicefunc, it should be
! 1141: a function fragment that when wrapped by "sub { my $res = shift; " and
! 1142: "}" returns a string representing what you want to have as the value. By
! 1143: default, the value will be the resource ID of the object ($res->{ID}).
! 1144:
! 1145: =back
! 1146:
! 1147: =cut
! 1148:
! 1149: no strict;
! 1150: @ISA = ("Apache::lonhelper::element");
! 1151: use strict;
! 1152:
! 1153: BEGIN {
! 1154: &Apache::lonxml::register('Apache::lonhelper::resource',
! 1155: ('resource', 'filterfunc',
! 1156: 'choicefunc', 'valuefunc'));
! 1157: }
! 1158:
! 1159: sub new {
! 1160: my $ref = Apache::lonhelper::element->new();
! 1161: bless($ref);
! 1162: }
! 1163:
! 1164: # CONSTRUCTION: Construct the message element from the XML
! 1165: sub start_resource {
! 1166: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1167:
! 1168: if ($target ne 'helper') {
! 1169: return '';
! 1170: }
! 1171:
! 1172: $paramHash->{'variable'} = $token->[2]{'variable'};
! 1173: $helper->declareVar($paramHash->{'variable'});
! 1174: return '';
! 1175: }
! 1176:
! 1177: sub end_resource {
! 1178: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1179:
! 1180: if ($target ne 'helper') {
! 1181: return '';
! 1182: }
! 1183: if (!defined($paramHash->{FILTER_FUNC})) {
! 1184: $paramHash->{FILTER_FUNC} = sub {return 1;};
! 1185: }
! 1186: if (!defined($paramHash->{CHOICE_FUNC})) {
! 1187: $paramHash->{CHOICE_FUNC} = sub {return 1;};
! 1188: }
! 1189: if (!defined($paramHash->{VALUE_FUNC})) {
! 1190: $paramHash->{VALUE_FUNC} = sub {my $res = shift; return $res->{ID}; };
! 1191: }
! 1192: Apache::lonhelper::resource->new();
1.4 bowersj2 1193: return '';
1194: }
1195:
1.5 ! bowersj2 1196: sub start_filterfunc {
! 1197: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1198:
! 1199: if ($target ne 'helper') {
! 1200: return '';
! 1201: }
! 1202:
! 1203: my $contents = Apache::lonxml::get_all_text('/filterfunc',
! 1204: $parser);
! 1205: $contents = 'sub { my $res = shift; ' . $contents . '}';
! 1206: $paramHash->{FILTER_FUNC} = eval $contents;
! 1207: }
! 1208:
! 1209: sub end_filterfunc { return ''; }
! 1210:
! 1211: sub start_choicefunc {
! 1212: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1213:
! 1214: if ($target ne 'helper') {
! 1215: return '';
! 1216: }
! 1217:
! 1218: my $contents = Apache::lonxml::get_all_text('/choicefunc',
! 1219: $parser);
! 1220: $contents = 'sub { my $res = shift; ' . $contents . '}';
! 1221: $paramHash->{CHOICE_FUNC} = eval $contents;
! 1222: }
! 1223:
! 1224: sub end_choicefunc { return ''; }
! 1225:
! 1226: sub start_valuefunc {
! 1227: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1228:
! 1229: if ($target ne 'helper') {
! 1230: return '';
! 1231: }
! 1232:
! 1233: my $contents = Apache::lonxml::get_all_text('/valuefunc',
! 1234: $parser);
! 1235: $contents = 'sub { my $res = shift; ' . $contents . '}';
! 1236: $paramHash->{VALUE_FUNC} = eval $contents;
! 1237: }
! 1238:
! 1239: sub end_valuefunc { return ''; }
! 1240:
! 1241: # A note, in case I don't get to this before I leave.
! 1242: # If someone complains about the "Back" button returning them
! 1243: # to the previous folder state, instead of returning them to
! 1244: # the previous helper state, the *correct* answer is for the helper
! 1245: # to keep track of how many times the user has manipulated the folders,
! 1246: # and feed that to the history.go() call in the helper rendering routines.
! 1247: # If done correctly, the helper itself can keep track of how many times
! 1248: # it renders the same states, so it doesn't go in just this state, and
! 1249: # you can lean on the browser back button to make sure it all chains
! 1250: # correctly.
! 1251: # Right now, though, I'm just forcing all folders open.
! 1252:
! 1253: sub render {
! 1254: my $self = shift;
! 1255: my $result = "";
! 1256: my $var = $self->{'variable'};
! 1257: my $curVal = $helper->{VARS}->{$var};
! 1258:
! 1259: if (defined $self->{ERROR_MSG}) {
! 1260: $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
! 1261: }
! 1262:
! 1263: my $filterFunc = $self->{FILTER_FUNC};
! 1264: my $choiceFunc = $self->{CHOICE_FUNC};
! 1265: my $valueFunc = $self->{VALUE_FUNC};
! 1266:
! 1267: # Create the composite function that renders the column on the nav map
! 1268: # have to admit any language that lets me do this can't be all bad
! 1269: # - Jeremy (Pythonista) ;-)
! 1270: my $checked = 0;
! 1271: my $renderColFunc = sub {
! 1272: my ($resource, $part, $params) = @_;
! 1273:
! 1274: if (!&$choiceFunc($resource)) {
! 1275: return '<td> </td>';
! 1276: } else {
! 1277: my $col = "<td><input type='radio' name='${var}.forminput' ";
! 1278: if (!$checked) {
! 1279: $col .= "checked ";
! 1280: $checked = 1;
! 1281: }
! 1282: $col .= "value='" .
! 1283: HTML::Entities::encode(&$valueFunc($resource))
! 1284: . "' /></td>";
! 1285: return $col;
! 1286: }
! 1287: };
! 1288:
! 1289: $ENV{'form.condition'} = 1;
! 1290: $result .=
! 1291: &Apache::lonnavmaps::render( { 'cols' => [$renderColFunc,
! 1292: Apache::lonnavmaps::resource()],
! 1293: 'showParts' => 0,
! 1294: 'url' => $helper->{URL},
! 1295: 'filterFunc' => $filterFunc,
! 1296: 'resource_no_folder_link' => 1 }
! 1297: );
! 1298:
! 1299: return $result;
! 1300: }
! 1301:
! 1302: sub postprocess {
! 1303: my $self = shift;
! 1304: if (defined($self->{NEXTSTATE})) {
! 1305: $helper->changeState($self->{NEXTSTATE});
! 1306: }
! 1307: }
! 1308:
! 1309: 1;
! 1310:
! 1311: package Apache::lonhelper::student;
! 1312:
! 1313: =pod
! 1314:
! 1315: =head2 Element: student
! 1316:
! 1317: Student elements display a choice of students enrolled in the current
! 1318: course. Currently it is primitive; this is expected to evolve later.
! 1319:
! 1320: Student elements take two attributes: "variable", which means what
! 1321: it usually does, and "multichoice", which if true allows the user
! 1322: to select multiple students.
! 1323:
! 1324: =cut
! 1325:
! 1326: no strict;
! 1327: @ISA = ("Apache::lonhelper::element");
! 1328: use strict;
! 1329:
! 1330:
! 1331:
! 1332: BEGIN {
! 1333: &Apache::lonxml::register('Apache::lonhelper::student',
! 1334: ('student'));
! 1335: }
! 1336:
! 1337: sub new {
! 1338: my $ref = Apache::lonhelper::element->new();
! 1339: bless($ref);
! 1340: }
1.4 bowersj2 1341:
1.5 ! bowersj2 1342: sub start_student {
1.4 bowersj2 1343: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1344:
1345: if ($target ne 'helper') {
1346: return '';
1347: }
1348:
1.5 ! bowersj2 1349: $paramHash->{'variable'} = $token->[2]{'variable'};
! 1350: $helper->declareVar($paramHash->{'variable'});
! 1351: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
! 1352: }
! 1353:
! 1354: sub end_student {
! 1355: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1356:
! 1357: if ($target ne 'helper') {
! 1358: return '';
! 1359: }
! 1360: Apache::lonhelper::student->new();
1.3 bowersj2 1361: }
1.5 ! bowersj2 1362:
! 1363: sub render {
! 1364: my $self = shift;
! 1365: my $result = '';
! 1366: my $buttons = '';
! 1367:
! 1368: if ($self->{'multichoice'}) {
! 1369: $result = <<SCRIPT;
! 1370: <script>
! 1371: function checkall(value) {
! 1372: for (i=0; i<document.forms.wizform.elements.length; i++) {
! 1373: document.forms.wizform.elements[i].checked=value;
! 1374: }
! 1375: }
! 1376: </script>
! 1377: SCRIPT
! 1378: $buttons = <<BUTTONS;
! 1379: <br />
! 1380: <input type="button" onclick="checkall(true)" value="Select All" />
! 1381: <input type="button" onclick="checkall(false)" value="Unselect All" />
! 1382: <br />
! 1383: BUTTONS
! 1384: }
! 1385:
! 1386: if (defined $self->{ERROR_MSG}) {
! 1387: $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
! 1388: }
! 1389:
! 1390: # Load up the students
! 1391: my $choices = &Apache::loncoursedata::get_classlist();
! 1392:
! 1393: my @keys = keys %{$choices};
! 1394:
! 1395: # Constants
! 1396: my $section = Apache::loncoursedata::CL_SECTION();
! 1397: my $fullname = Apache::loncoursedata::CL_FULLNAME();
! 1398:
! 1399: # Sort by: Section, name
! 1400: @keys = sort {
! 1401: if ($choices->{$a}->[$section] ne $choices->{$b}->[$section]) {
! 1402: return $choices->{$a}->[$section] cmp $choices->{$b}->[$section];
! 1403: }
! 1404: return $choices->{$a}->[$fullname] cmp $choices->{$b}->[$fullname];
! 1405: } @keys;
! 1406:
! 1407: my $type = 'radio';
! 1408: if ($self->{'multichoice'}) { $type = 'checkbox'; }
! 1409: $result .= "<table cellspacing='2' cellpadding='2' border='0'>\n";
! 1410: $result .= "<tr><td></td><td align='center'><b>Student Name</b></td>".
! 1411: "<td align='center'><b>Section</b></td></tr>";
! 1412:
! 1413: my $checked = 0;
! 1414: foreach (@keys) {
! 1415: $result .= "<tr><td><input type='$type' name='" .
! 1416: $self->{'variable'} . '.forminput' . "'";
! 1417:
! 1418: if (!$self->{'multichoice'} && !$checked) {
! 1419: $result .= " checked ";
! 1420: $checked = 1;
! 1421: }
! 1422: $result .=
! 1423: " value='" . HTML::Entities::encode($_)
! 1424: . "' /></td><td>"
! 1425: . HTML::Entities::encode($choices->{$_}->[$fullname])
! 1426: . "</td><td align='center'>"
! 1427: . HTML::Entities::encode($choices->{$_}->[$section])
! 1428: . "</td></tr>\n";
! 1429: }
! 1430:
! 1431: $result .= "</table>\n\n";
! 1432: $result .= $buttons;
1.4 bowersj2 1433:
1.5 ! bowersj2 1434: return $result;
! 1435: }
! 1436:
! 1437: 1;
! 1438:
! 1439: package Apache::lonhelper::files;
! 1440:
! 1441: =pod
! 1442:
! 1443: =head2 Element: files
! 1444:
! 1445: files allows the users to choose files from a given directory on the
! 1446: server. It is always multichoice and stores the result as a triple-pipe
! 1447: delimited entry in the helper variables.
! 1448:
! 1449: Since it is extremely unlikely that you can actually code a constant
! 1450: representing the directory you wish to allow the user to search, <files>
! 1451: takes a subroutine that returns the name of the directory you wish to
! 1452: have the user browse.
! 1453:
! 1454: files accepts the attribute "variable" to control where the files chosen
! 1455: are put. It accepts the attribute "multichoice" as the other attribute,
! 1456: defaulting to false, which if true will allow the user to select more
! 1457: then one choice.
! 1458:
! 1459: <files> accepts three subtags. One is the "nextstate" sub-tag that works
! 1460: as it does with the other tags. Another is a <filechoice> sub tag that
! 1461: is Perl code that, when surrounded by "sub {" and "}" will return a
! 1462: string representing what directory on the server to allow the user to
! 1463: choose files from. Finally, the <filefilter> subtag should contain Perl
! 1464: code that when surrounded by "sub { my $filename = shift; " and "}",
! 1465: returns a true value if the user can pick that file, or false otherwise.
! 1466: The filename passed to the function will be just the name of the file,
! 1467: with no path info.
! 1468:
! 1469: =cut
! 1470:
! 1471: no strict;
! 1472: @ISA = ("Apache::lonhelper::element");
! 1473: use strict;
! 1474:
! 1475: BEGIN {
! 1476: &Apache::lonxml::register('Apache::lonhelper::files',
! 1477: ('files', 'filechoice', 'filefilter'));
! 1478: }
! 1479:
! 1480: sub new {
! 1481: my $ref = Apache::lonhelper::element->new();
! 1482: bless($ref);
! 1483: }
! 1484:
! 1485: sub start_files {
! 1486: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1487:
! 1488: if ($target ne 'helper') {
! 1489: return '';
! 1490: }
! 1491: $paramHash->{'variable'} = $token->[2]{'variable'};
! 1492: $helper->declareVar($paramHash->{'variable'});
! 1493: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
! 1494: }
! 1495:
! 1496: sub end_files {
! 1497: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1498:
! 1499: if ($target ne 'helper') {
! 1500: return '';
! 1501: }
! 1502: if (!defined($paramHash->{FILTER_FUNC})) {
! 1503: $paramHash->{FILTER_FUNC} = sub { return 1; };
! 1504: }
! 1505: Apache::lonhelper::files->new();
! 1506: }
! 1507:
! 1508: sub start_filechoice {
! 1509: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1510:
! 1511: if ($target ne 'helper') {
! 1512: return '';
! 1513: }
! 1514: $paramHash->{'filechoice'} = Apache::lonxml::get_all_text('/filechoice',
! 1515: $parser);
! 1516: }
! 1517:
! 1518: sub end_filechoice { return ''; }
! 1519:
! 1520: sub start_filefilter {
! 1521: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
! 1522:
! 1523: if ($target ne 'helper') {
! 1524: return '';
! 1525: }
! 1526:
! 1527: my $contents = Apache::lonxml::get_all_text('/filefilter',
! 1528: $parser);
! 1529: $contents = 'sub { my $filename = shift; ' . $contents . '}';
! 1530: $paramHash->{FILTER_FUNC} = eval $contents;
! 1531: }
! 1532:
! 1533: sub end_filefilter { return ''; }
1.3 bowersj2 1534:
1535: sub render {
1536: my $self = shift;
1.5 ! bowersj2 1537: my $result = '';
! 1538: my $var = $self->{'variable'};
! 1539:
! 1540: my $subdirFunc = eval('sub {' . $self->{'filechoice'} . '}');
! 1541: my $subdir = &$subdirFunc();
! 1542:
! 1543: my $filterFunc = $self->{FILTER_FUNC};
! 1544: my $buttons = '';
! 1545:
! 1546: if ($self->{'multichoice'}) {
! 1547: $result = <<SCRIPT;
! 1548: <script>
! 1549: function checkall(value) {
! 1550: for (i=0; i<document.forms.wizform.elements.length; i++) {
! 1551: ele = document.forms.wizform.elements[i];
! 1552: if (ele.type == "checkbox") {
! 1553: document.forms.wizform.elements[i].checked=value;
! 1554: }
! 1555: }
! 1556: }
! 1557: </script>
! 1558: SCRIPT
! 1559: my $buttons = <<BUTTONS;
! 1560: <br />
! 1561: <input type="button" onclick="checkall(true)" value="Select All" />
! 1562: <input type="button" onclick="checkall(false)" value="Unselect All" />
! 1563: <br />
! 1564: BUTTONS
! 1565: }
! 1566:
! 1567: # Get the list of files in this directory.
! 1568: my @fileList;
! 1569:
! 1570: # If the subdirectory is in local CSTR space
! 1571: if ($subdir =~ m|/home/([^/]+)/public_html|) {
! 1572: my $user = $1;
! 1573: my $domain = $Apache::lonnet::perlvar{'lonDefDomain'};
! 1574: @fileList = &Apache::lonnet::dirlist($subdir, $domain, $user, '');
! 1575: } else {
! 1576: # local library server resource space
! 1577: @fileList = &Apache::lonnet::dirlist($subdir, $ENV{'user.domain'}, $ENV{'user.name'}, '');
! 1578: }
1.3 bowersj2 1579:
1.5 ! bowersj2 1580: $result .= $buttons;
! 1581:
! 1582: $result .= '<table border="0" cellpadding="1" cellspacing="1">';
! 1583:
! 1584: # Keeps track if there are no choices, prints appropriate error
! 1585: # if there are none.
! 1586: my $choices = 0;
! 1587: my $type = 'radio';
! 1588: if ($self->{'multichoice'}) {
! 1589: $type = 'checkbox';
! 1590: }
! 1591: # Print each legitimate file choice.
! 1592: for my $file (@fileList) {
! 1593: $file = (split(/&/, $file))[0];
! 1594: if ($file eq '.' || $file eq '..') {
! 1595: next;
! 1596: }
! 1597: my $fileName = $subdir .'/'. $file;
! 1598: if (&$filterFunc($file)) {
! 1599: $result .= '<tr><td align="right">' .
! 1600: "<input type='$type' name='" . $var
! 1601: . ".forminput' value='" . HTML::Entities::encode($fileName) .
! 1602: "'";
! 1603: if (!$self->{'multichoice'} && $choices == 0) {
! 1604: $result .= ' checked';
! 1605: }
! 1606: $result .= "/></td><td>" . $file . "</td></tr>\n";
! 1607: $choices++;
! 1608: }
! 1609: }
! 1610:
! 1611: $result .= "</table>\n";
! 1612:
! 1613: if (!$choices) {
! 1614: $result .= '<font color="#FF0000">There are no files available to select in this directory. Please go back and select another option.</font><br /><br />';
! 1615: }
! 1616:
! 1617: $result .= $buttons;
! 1618:
! 1619: return $result;
1.4 bowersj2 1620: }
1.5 ! bowersj2 1621:
1.4 bowersj2 1622: sub postprocess {
1623: my $self = shift;
1.5 ! bowersj2 1624: if ($self->{'multichoice'}) {
! 1625: $self->process_multiple_choices($self->{'variable'}.'.forminput',
! 1626: $self->{'variable'});
! 1627: }
! 1628: if (defined($self->{NEXTSTATE})) {
! 1629: $helper->changeState($self->{NEXTSTATE});
1.3 bowersj2 1630: }
1631: }
1.5 ! bowersj2 1632:
1.4 bowersj2 1633: 1;
1.3 bowersj2 1634:
1.1 bowersj2 1635: __END__
1.3 bowersj2 1636:
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