File: /home/mbp/domains/mbp.ac.th/public_html/old/main/blocks/moodleblock.class.php
<?php // $Id$
/**
* This file contains the parent class for moodle blocks, block_base.
*
* @author Jon Papaioannou
* @version $Id$
* @license http://www.gnu.org/copyleft/gpl.html GNU Public License
* @package blocks
*/
/// Constants
/**
* Block type of list. Contents of block should be set as an associative array in the content object as items ($this->content->items). Optionally include footer text in $this->content->footer.
*/
define('BLOCK_TYPE_LIST', 1);
/**
* Block type of text. Contents of block should be set to standard html text in the content object as items ($this->content->text). Optionally include footer text in $this->content->footer.
*/
define('BLOCK_TYPE_TEXT', 2);
/**
* Class for describing a moodle block, all Moodle blocks derive from this class
*
* @author Jon Papaioannou
* @package blocks
*/
class block_base {
/**
* Internal var for storing/caching translated strings
* @var string $str
*/
var $str;
/**
* The title of the block to be displayed in the block title area.
* @var string $title
*/
var $title = NULL;
/**
* The type of content that this block creates. Currently support options - BLOCK_TYPE_LIST, BLOCK_TYPE_TEXT
* @var int $content_type
*/
var $content_type = BLOCK_TYPE_TEXT;
/**
* An object to contain the information to be displayed in the block.
* @var stdObject $content
*/
var $content = NULL;
/**
* A string generated by {@link _add_edit_controls()} to display block manipulation links when the user is in editing mode.
* @var string $edit_controls
*/
var $edit_controls = NULL;
/**
* The current version that the block type defines.
* @var string $version
*/
var $version = NULL;
/**
* The initialized instance of this block object.
* @var block $instance
*/
var $instance = NULL;
/**
* An object containing the instance configuration information for the current instance of this block.
* @var stdObject $config
*/
var $config = NULL;
/**
* How often the cronjob should run, 0 if not at all.
* @var int $cron
*/
var $cron = NULL;
/**
* Indicates blocked is pinned - can not be moved, always present, does not have own context
*/
var $pinned = false;
/// Class Functions
/**
* The class constructor
*
*/
function block_base() {
$this->init();
}
/**
* Fake constructor to keep PHP5 happy
*
*/
function __construct() {
$this->block_base();
}
/**
* Function that can be overridden to do extra setup after
* the database install. (Called once per block, not per instance!)
*/
function after_install() {
}
/**
* Function that can be overridden to do extra cleanup before
* the database tables are deleted. (Called once per block, not per instance!)
*/
function before_delete() {
}
/**
* Function that can be overridden to do extra setup after a block instance has been
* restored from backup. For example, it may need to alter any dates that the block
* stores, if the $restore->course_startdateoffset is set.
*/
function after_restore($restore) {
}
/**
* Enable custom instance data section in backup and restore.
*
* If return true, then {@link instance_backup()} and
* {@link instance_restore()} will be called during
* backup/restore routines.
*
* @return boolean
**/
function backuprestore_instancedata_used() {
return false;
}
/**
* Allows the block class to have a backup routine. Handy
* when the block has its own tables that have foreign keys to
* other tables (example: user table).
*
* Note: at the time of writing this comment, the indent level
* for the {@link full_tag()} should start at 5.
*
* @param resource $bf Backup File
* @param object $preferences Backup preferences
* @return boolean
**/
function instance_backup($bf, $preferences) {
return true;
}
/**
* Allows the block class to restore its backup routine.
*
* Should not return false if data is empty
* because old backups would not contain block instance backup data.
*
* @param object $restore Standard restore object
* @param object $data Object from backup_getid for this block instance
* @return boolean
**/
function instance_restore($restore, $data) {
return true;
}
/**
* Will be called before an instance of this block is backed up, so that any links in
* in config can be encoded. For example config->text, for the HTML block
* @return string
*/
function get_backup_encoded_config() {
return base64_encode(serialize($this->config));
}
/**
* Return the content encoded to support interactivities linking. This function is
* called automatically from the backup procedure by {@link backup_encode_absolute_links()}.
*
* NOTE: There is no block instance when this method is called.
*
* @param string $content Content to be encoded
* @param object $restore Restore preferences object
* @return string The encoded content
**/
function encode_content_links($content, $restore) {
return $content;
}
/**
* This function makes all the necessary calls to {@link restore_decode_content_links_worker()}
* function in order to decode contents of this block from the backup
* format to destination site/course in order to mantain inter-activities
* working in the backup/restore process.
*
* This is called from {@link restore_decode_content_links()} function in the restore process.
*
* NOTE: There is no block instance when this method is called.
*
* @param object $restore Standard restore object
* @return boolean
**/
function decode_content_links_caller($restore) {
return true;
}
/**
* Return content decoded to support interactivities linking.
* This is called automatically from
* {@link restore_decode_content_links_worker()} function
* in the restore process.
*
* NOTE: There is no block instance when this method is called.
*
* @param string $content Content to be dencoded
* @param object $restore Restore preferences object
* @return string The dencoded content
**/
function decode_content_links($content, $restore) {
return $content;
}
/**
* Returns the block name, as present in the class name,
* the database, the block directory, etc etc.
*
* @return string
*/
function name() {
// Returns the block name, as present in the class name,
// the database, the block directory, etc etc.
static $myname;
if ($myname === NULL) {
$myname = strtolower(get_class($this));
$myname = substr($myname, strpos($myname, '_') + 1);
}
return $myname;
}
/**
* Parent class version of this function simply returns NULL
* This should be implemented by the derived class to return
* the content object.
*
* @return stdObject
*/
function get_content() {
// This should be implemented by the derived class.
return NULL;
}
/**
* Returns the class $title var value.
*
* Intentionally doesn't check if a title is set.
* This is already done in {@link _self_test()}
*
* @return string $this->title
*/
function get_title() {
// Intentionally doesn't check if a title is set. This is already done in _self_test()
return $this->title;
}
/**
* Returns the class $content_type var value.
*
* Intentionally doesn't check if content_type is set.
* This is already done in {@link _self_test()}
*
* @return string $this->content_type
*/
function get_content_type() {
// Intentionally doesn't check if a content_type is set. This is already done in _self_test()
return $this->content_type;
}
/**
* Returns the class $version var value.
*
* Intentionally doesn't check if a version is set.
* This is already done in {@link _self_test()}
*
* @return string $this->version
*/
function get_version() {
// Intentionally doesn't check if a version is set. This is already done in _self_test()
return $this->version;
}
/**
* Returns true or false, depending on whether this block has any content to display
* and whether the user has permission to view the block
*
* @return boolean
*/
function is_empty() {
if (empty($this->instance->pinned)) {
$context = get_context_instance(CONTEXT_BLOCK, $this->instance->id);
} else {
$context = get_context_instance(CONTEXT_SYSTEM); // pinned blocks do not have own context
}
if ( !has_capability('moodle/block:view', $context) ) {
return true;
}
$this->get_content();
return(empty($this->content->text) && empty($this->content->footer));
}
/**
* First sets the current value of $this->content to NULL
* then calls the block's {@link get_content()} function
* to set its value back.
*
* @return stdObject
*/
function refresh_content() {
// Nothing special here, depends on content()
$this->content = NULL;
return $this->get_content();
}
/**
* Display the block!
*/
function _print_block() {
global $COURSE;
// is_empty() includes a call to get_content()
if ($this->is_empty() && empty($COURSE->javascriptportal)) {
if (empty($this->edit_controls)) {
// No content, no edit controls, so just shut up
return;
} else {
// No content but editing, so show something at least
$this->_print_shadow();
}
} else {
if ($this->hide_header() && empty($this->edit_controls)) {
// Header wants to hide, no edit controls to show, so no header it is
print_side_block(NULL, $this->content->text, NULL, NULL, $this->content->footer, $this->html_attributes());
} else {
// The full treatment, please. Include the title text.
print_side_block($this->_title_html(), $this->content->text, NULL, NULL, $this->content->footer, $this->html_attributes(), $this->title);
}
}
}
/**
* Block contents are missing. Simply display an empty block so that
* edit controls are accessbile to the user and they are aware that this
* block is in place, even if empty.
*/
function _print_shadow() {
print_side_block($this->_title_html(), ' ', NULL, NULL, '', array('class' => 'hidden'), $this->title);
}
function _title_html() {
global $CFG;
//Accessibility: validation, can't have <div> inside <h2>, use <span>.
$title = '<div class="title">';
if (!empty($CFG->allowuserblockhiding)) {
//Accessibility: added 'alt' text for the +- icon.
//Theme the buttons using, Admin - Miscellaneous - smartpix.
$strshow = addslashes_js(get_string('showblocka', 'access', strip_tags($this->title)));
$strhide = addslashes_js(get_string('hideblocka', 'access', strip_tags($this->title)));
$title .= '<input type="image" src="'.$CFG->pixpath.'/t/switch_minus.gif" '.
'id="togglehide_inst'.$this->instance->id.'" '.
'onclick="elementToggleHide(this, true, function(el) {'.
'return findParentNode(el, \'DIV\', \'sideblock\'); },'.
' \''.$strshow.'\', \''.$strhide.'\'); return false;" '.
'alt="'.$strhide.'" title="'.$strhide.'" class="hide-show-image" />';
}
//Accesssibility: added H2 (was in, weblib.php: print_side_block)
$title .= '<h2>'.$this->title.'</h2>';
if ($this->edit_controls !== NULL) {
$title .= $this->edit_controls;
}
$title .= '</div>';
return $title;
}
/**
* Sets class $edit_controls var with correct block manipulation links.
*
* @uses $CFG
* @uses $USER
* @param stdObject $options ?
* @todo complete documenting this function. Define $options.
*/
function _add_edit_controls($options) {
global $CFG, $USER, $PAGE;
if (empty($this->instance->pinned)) {
$context = get_context_instance(CONTEXT_BLOCK, $this->instance->id);
} else {
$context = get_context_instance(CONTEXT_SYSTEM); // pinned blocks do not have own context
}
// context for site or course, i.e. participant list etc
// check to see if user can edit site or course blocks.
// blocks can appear on other pages such as mod and blog pages...
switch ($this->instance->pagetype) {
case 'course-view':
if (!has_capability('moodle/site:manageblocks', $context)) {
return null;
}
break;
default:
break;
}
if (!isset($this->str)) {
$this->str->delete = get_string('delete');
$this->str->moveup = get_string('moveup');
$this->str->movedown = get_string('movedown');
$this->str->moveright = get_string('moveright');
$this->str->moveleft = get_string('moveleft');
$this->str->hide = get_string('hide');
$this->str->show = get_string('show');
$this->str->configure = get_string('configuration');
$this->str->assignroles = get_string('assignroles', 'role');
}
// RTL support - exchange right and left arrows
if (right_to_left()) {
$rightarrow = 'left.gif';
$leftarrow = 'right.gif';
} else {
$rightarrow = 'right.gif';
$leftarrow = 'left.gif';
}
$movebuttons = '<div class="commands">';
if ($this->instance->visible) {
$icon = '/t/hide.gif';
$title = $this->str->hide;
} else {
$icon = '/t/show.gif';
$title = $this->str->show;
}
if (empty($this->instance->pageid)) {
$this->instance->pageid = 0;
}
if (!empty($PAGE->type) and ($this->instance->pagetype == $PAGE->type) and $this->instance->pageid == $PAGE->id) {
$page = $PAGE;
} else {
$page = page_create_object($this->instance->pagetype, $this->instance->pageid);
}
$script = $page->url_get_full(array('instanceid' => $this->instance->id, 'sesskey' => $USER->sesskey));
if (empty($this->instance->pinned)) {
$movebuttons .= '<a class="icon roles" title="'. $this->str->assignroles .'" href="'.$CFG->wwwroot.'/'.$CFG->admin.'/roles/assign.php?contextid='.$context->id.'">' .
'<img src="'.$CFG->pixpath.'/i/roles.gif" alt="'.$this->str->assignroles.'" /></a>';
}
if ($this->user_can_edit()) {
$movebuttons .= '<a class="icon hide" title="'. $title .'" href="'.$script.'&blockaction=toggle">' .
'<img src="'. $CFG->pixpath.$icon .'" alt="'.$title.'" /></a>';
}
if ($options & BLOCK_CONFIGURE && $this->user_can_edit()) {
$movebuttons .= '<a class="icon edit" title="'. $this->str->configure .'" href="'.$script.'&blockaction=config">' .
'<img src="'. $CFG->pixpath .'/t/edit.gif" alt="'. $this->str->configure .'" /></a>';
}
if ($this->user_can_addto($page)) {
$movebuttons .= '<a class="icon delete" title="'. $this->str->delete .'" href="'.$script.'&blockaction=delete">' .
'<img src="'. $CFG->pixpath .'/t/delete.gif" alt="'. $this->str->delete .'" /></a>';
}
if ($options & BLOCK_MOVE_LEFT) {
$movebuttons .= '<a class="icon left" title="'. $this->str->moveleft .'" href="'.$script.'&blockaction=moveleft">' .
'<img src="'. $CFG->pixpath .'/t/'.$leftarrow.'" alt="'. $this->str->moveleft .'" /></a>';
}
if ($options & BLOCK_MOVE_UP) {
$movebuttons .= '<a class="icon up" title="'. $this->str->moveup .'" href="'.$script.'&blockaction=moveup">' .
'<img src="'. $CFG->pixpath .'/t/up.gif" alt="'. $this->str->moveup .'" /></a>';
}
if ($options & BLOCK_MOVE_DOWN) {
$movebuttons .= '<a class="icon down" title="'. $this->str->movedown .'" href="'.$script.'&blockaction=movedown">' .
'<img src="'. $CFG->pixpath .'/t/down.gif" alt="'. $this->str->movedown .'" /></a>';
}
if ($options & BLOCK_MOVE_RIGHT) {
$movebuttons .= '<a class="icon right" title="'. $this->str->moveright .'" href="'.$script.'&blockaction=moveright">' .
'<img src="'. $CFG->pixpath .'/t/'.$rightarrow.'" alt="'. $this->str->moveright .'" /></a>';
}
$movebuttons .= '</div>';
$this->edit_controls = $movebuttons;
}
/**
* Tests if this block has been implemented correctly.
* Also, $errors isn't used right now
*
* @return boolean
*/
function _self_test() {
// Tests if this block has been implemented correctly.
// Also, $errors isn't used right now
$errors = array();
$correct = true;
if ($this->get_title() === NULL) {
$errors[] = 'title_not_set';
$correct = false;
}
if (!in_array($this->get_content_type(), array(BLOCK_TYPE_LIST, BLOCK_TYPE_TEXT))) {
$errors[] = 'invalid_content_type';
$correct = false;
}
//following selftest was not working when roles&capabilities were used from block
/* if ($this->get_content() === NULL) {
$errors[] = 'content_not_set';
$correct = false;
}*/
if ($this->get_version() === NULL) {
$errors[] = 'version_not_set';
$correct = false;
}
$formats = $this->applicable_formats();
if (empty($formats) || array_sum($formats) === 0) {
$errors[] = 'no_formats';
$correct = false;
}
$width = $this->preferred_width();
if (!is_int($width) || $width <= 0) {
$errors[] = 'invalid_width';
$correct = false;
}
return $correct;
}
/**
* Subclasses should override this and return true if the
* subclass block has a config_global.html file.
*
* @return boolean
*/
function has_config() {
return false;
}
/**
* Default behavior: print the config_global.html file
* You don't need to override this if you're satisfied with the above
*
* @uses $CFG
* @return boolean
*/
function config_print() {
// Default behavior: print the config_global.html file
// You don't need to override this if you're satisfied with the above
if (!$this->has_config()) {
return false;
}
global $CFG;
print_simple_box_start('center', '', '', 5, 'blockconfigglobal');
include($CFG->dirroot.'/blocks/'. $this->name() .'/config_global.html');
print_simple_box_end();
return true;
}
/**
* Default behavior: save all variables as $CFG properties
* You don't need to override this if you 're satisfied with the above
*
* @param array $data
* @return boolean
*/
function config_save($data) {
foreach ($data as $name => $value) {
set_config($name, $value);
}
return true;
}
/**
* Default case: the block can be used in all course types
* @return array
* @todo finish documenting this function
*/
function applicable_formats() {
// Default case: the block can be used in courses and site index, but not in activities
return array('all' => true, 'mod' => false, 'tag' => false);
}
/**
* Default case: the block wants to be 180 pixels wide
* @return int
*/
function preferred_width() {
return 180;
}
/**
* Default return is false - header will be shown
* @return boolean
*/
function hide_header() {
return false;
}
/**
* Default case: an id with the instance and a class with our name in it
* @return array
* @todo finish documenting this function
*/
function html_attributes() {
return array('id' => 'inst'.$this->instance->id, 'class' => 'block_'. $this->name());
}
/**
* Given an instance set the class var $instance to it and
* load class var $config
* @param block $instance
* @todo add additional documentation to further explain the format of instance and config
*/
function _load_instance($instance) {
if (!empty($instance->configdata)) {
$this->config = unserialize(base64_decode($instance->configdata));
}
// [pj] This line below is supposed to be an optimization (we don't need configdata anymore)
// but what it does is break in PHP5 because the same instance object will be passed to
// this function twice in each page view, and the second time it won't have any configdata
// so it won't work correctly. Thus it's commented out.
// unset($instance->configdata);
$this->instance = $instance;
$this->specialization();
}
/**
* This function is called on your subclass right after an instance is loaded
* Use this function to act on instance data just after it's loaded and before anything else is done
* For instance: if your block will have different title's depending on location (site, course, blog, etc)
*/
function specialization() {
// Just to make sure that this method exists.
}
/**
* Is each block of this type going to have instance-specific configuration?
* Normally, this setting is controlled by {@link instance_allow_multiple}: if multiple
* instances are allowed, then each will surely need its own configuration. However, in some
* cases it may be necessary to provide instance configuration to blocks that do not want to
* allow multiple instances. In that case, make this function return true.
* I stress again that this makes a difference ONLY if {@link instance_allow_multiple} returns false.
* @return boolean
* @todo finish documenting this function by explaining per-instance configuration further
*/
function instance_allow_config() {
return false;
}
/**
* Are you going to allow multiple instances of each block?
* If yes, then it is assumed that the block WILL USE per-instance configuration
* @return boolean
* @todo finish documenting this function by explaining per-instance configuration further
*/
function instance_allow_multiple() {
// Are you going to allow multiple instances of each block?
// If yes, then it is assumed that the block WILL USE per-instance configuration
return false;
}
/**
* Default behavior: print the config_instance.html file
* You don't need to override this if you're satisfied with the above
*
* @uses $CFG
* @return boolean
* @todo finish documenting this function
*/
function instance_config_print() {
// Default behavior: print the config_instance.html file
// You don't need to override this if you're satisfied with the above
if (!$this->instance_allow_multiple() && !$this->instance_allow_config()) {
return false;
}
global $CFG;
if (is_file($CFG->dirroot .'/blocks/'. $this->name() .'/config_instance.html')) {
print_simple_box_start('center', '', '', 5, 'blockconfiginstance');
include($CFG->dirroot .'/blocks/'. $this->name() .'/config_instance.html');
print_simple_box_end();
} else {
notice(get_string('blockconfigbad'), str_replace('blockaction=', 'dummy=', qualified_me()));
}
return true;
}
/**
* Serialize and store config data
* @return boolean
* @todo finish documenting this function
*/
function instance_config_save($data,$pinned=false) {
$data = stripslashes_recursive($data);
$this->config = $data;
$table = 'block_instance';
if (!empty($pinned)) {
$table = 'block_pinned';
}
return set_field($table, 'configdata', base64_encode(serialize($data)), 'id', $this->instance->id);
}
/**
* Replace the instance's configuration data with those currently in $this->config;
* @return boolean
* @todo finish documenting this function
*/
function instance_config_commit($pinned=false) {
$table = 'block_instance';
if (!empty($pinned)) {
$table = 'block_pinned';
}
return set_field($table, 'configdata', base64_encode(serialize($this->config)), 'id', $this->instance->id);
}
/**
* Do any additional initialization you may need at the time a new block instance is created
* @return boolean
* @todo finish documenting this function
*/
function instance_create() {
return true;
}
/**
* Delete everything related to this instance if you have been using persistent storage other than the configdata field.
* @return boolean
* @todo finish documenting this function
*/
function instance_delete() {
return true;
}
/**
* Allows the block class to have a say in the user's ability to edit (i.e., configure) blocks of this type.
* The framework has first say in whether this will be allowed (e.g., no editing allowed unless in edit mode)
* but if the framework does allow it, the block can still decide to refuse.
* @return boolean
* @todo finish documenting this function
*/
function user_can_edit() {
return true;
}
/**
* Allows the block class to have a say in the user's ability to create new instances of this block.
* The framework has first say in whether this will be allowed (e.g., no adding allowed unless in edit mode)
* but if the framework does allow it, the block can still decide to refuse.
* This function has access to the complete page object, the creation related to which is being determined.
* @return boolean
* @todo finish documenting this function
*/
function user_can_addto($page) {
return true;
}
function get_extra_capabilities() {
return array('moodle/block:view');
}
}
/**
* Specialized class for displaying a block with a list of icons/text labels
*
* @author Jon Papaioannou
* @package blocks
*/
class block_list extends block_base {
var $content_type = BLOCK_TYPE_LIST;
function is_empty() {
if (empty($this->instance->pinned)) {
$context = get_context_instance(CONTEXT_BLOCK, $this->instance->id);
} else {
$context = get_context_instance(CONTEXT_SYSTEM); // pinned blocks do not have own context
}
if ( !has_capability('moodle/block:view', $context) ) {
return true;
}
$this->get_content();
return (empty($this->content->items) && empty($this->content->footer));
}
function _print_block() {
global $COURSE;
// is_empty() includes a call to get_content()
if ($this->is_empty() && empty($COURSE->javascriptportal)) {
if (empty($this->edit_controls)) {
// No content, no edit controls, so just shut up
return;
} else {
// No content but editing, so show something at least
$this->_print_shadow();
}
} else {
if ($this->hide_header() && empty($this->edit_controls)) {
// Header wants to hide, no edit controls to show, so no header it is
print_side_block(NULL, '', $this->content->items, $this->content->icons,
$this->content->footer, $this->html_attributes());
} else {
// The full treatment, please. Include the title text.
print_side_block($this->_title_html(), '', $this->content->items, $this->content->icons,
$this->content->footer, $this->html_attributes(), $this->title);
}
}
}
}
?>