editable = $editable;
$this->attributes = $attributes;
$this->type = $type;
$this->page = $page;
$this->pageparamname = $pageparamname;
$this->itemsperpage = $itemsperpage;
if ($pageurl === null) {
$this->pageurl = new moodle_url();
$this->pageurl->params(array($this->pageparamname => $this->page));
} else {
$this->pageurl = $pageurl;
}
}
/**
* Returns html string.
*
* @param integer $indent depth of indentation.
*/
function to_html($indent=0, $extraargs=array()) {
if (count($this->items)) {
$tabs = str_repeat("\t", $indent);
$first = true;
$itemiter = 1;
$lastitem = '';
$html = '';
foreach ($this->items as $item) {
$last = (count($this->items) == $itemiter);
if ($this->editable) {
$item->set_icon_html($first, $last, $lastitem);
}
if ($itemhtml = $item->to_html($indent+1, $extraargs)) {
$html .= "$tabs\t
attributes))?(' '.$item->attributes):'').">";
$html .= $itemhtml;
$html .= "\n";
}
$first = false;
$lastitem = $item;
$itemiter++;
}
} else {
$html = '';
}
if ($html) { //if there are list items to display then wrap them in ul / ol tag.
$tabs = str_repeat("\t", $indent);
$html = $tabs.'<'.$this->type.((!empty($this->attributes))?(' '.$this->attributes):'').">\n".$html;
$html .= $tabs."".$this->type.">\n";
} else {
$html ='';
}
return $html;
}
/**
* Recurse down the tree and find an item by it's id.
*
* @param integer $id
* @param boolean $suppresserror error if not item found?
* @return list_item *copy* or null if item is not found
*/
function find_item($id, $suppresserror = false) {
if (isset($this->items)) {
foreach ($this->items as $key => $child) {
if ($child->id == $id) {
return $this->items[$key];
}
}
foreach (array_keys($this->items) as $key) {
$thischild =& $this->items[$key];
$ref = $thischild->children->find_item($id, true);//error always reported at top level
if ($ref !== null) {
return $ref;
}
}
}
if (!$suppresserror) {
print_error('listnoitem');
}
return null;
}
function add_item(&$item) {
$this->items[] =& $item;
}
function set_parent(&$parent) {
$this->parentitem =& $parent;
}
/**
* Produces a hierarchical tree of list items from a flat array of records.
* 'parent' field is expected to point to a parent record.
* records are already sorted.
* If the parent field doesn't point to another record in the array then this is
* a top level list
*
* @param integer $offset how many list toplevel items are there in lists before this one
* @return array(boolean, integer) whether there is more than one page, $offset + how many toplevel items where there in this list.
*
*/
function list_from_records($paged = false, $offset = 0) {
$this->paged = $paged;
$this->offset = $offset;
$this->get_records();
$records = $this->records;
$page = $this->page;
if (!empty($page)) {
$this->firstitem = ($page - 1) * $this->itemsperpage;
$this->lastitem = $this->firstitem + $this->itemsperpage - 1;
}
$itemiter = $offset;
//make a simple array which is easier to search
$this->childparent = array();
foreach ($records as $record) {
$this->childparent[$record->id] = $record->parent;
}
//create top level list items and they're responsible for creating their children
foreach ($records as $record) {
if (!array_key_exists($record->parent, $this->childparent)) {
//if this record is not a child of another record then
$inpage = ($itemiter >= $this->firstitem && $itemiter <= $this->lastitem);
//make list item for top level for all items
//we need the info about the top level items for reordering peers.
if ($this->parentitem!==null) {
$newattributes = $this->parentitem->attributes;
} else {
$newattributes = '';
}
$this->items[$itemiter] =& new $this->listitemclassname($record, $this, $newattributes, $inpage);
if ($inpage) {
$this->items[$itemiter]->create_children($records, $this->childparent, $record->id);
} else {
//don't recurse down the tree for items that are not on this page
$this->paged = true;
}
$itemiter++;
}
}
return array($this->paged, $itemiter);
}
/**
* Should be overriden to return an array of records of list items.
*
*/
function get_records() {
}
/**
* display list of page numbers for navigation
*/
function display_page_numbers() {
$html = '';
$topcount = count($this->items);
$this->pagecount = (integer) ceil(($topcount + $this->offset)/ QUESTION_PAGE_LENGTH );
if (!empty($this->page) && ($this->paged)) {
$html = "";
}
return $html;
}
/**
* Returns an array of ids of peers of an item.
*
* @param int itemid - if given, restrict records to those with this parent id.
* @return array peer ids
*/
function get_items_peers($itemid) {
$itemref = $this->find_item($itemid);
$peerids = $itemref->parentlist->get_child_ids();
return $peerids;
}
/**
* Returns an array of ids of child items.
*
* @return array peer ids
*/
function get_child_ids() {
$childids = array();
foreach ($this->items as $child) {
$childids[] = $child->id;
}
return $childids;
}
/**
* Move a record up or down
*
* @param string $direction up / down
* @param integer $id
*/
function move_item_up_down($direction, $id) {
$peers = $this->get_items_peers($id);
$itemkey = array_search($id, $peers);
switch ($direction) {
case 'down' :
if (isset($peers[$itemkey+1])) {
$olditem = $peers[$itemkey+1];
$peers[$itemkey+1] = $id;
$peers[$itemkey] = $olditem;
} else {
print_error('listcantmoveup');
}
break;
case 'up' :
if (isset($peers[$itemkey-1])) {
$olditem = $peers[$itemkey-1];
$peers[$itemkey-1] = $id;
$peers[$itemkey] = $olditem;
} else {
print_error('listcantmovedown');
}
break;
}
$this->reorder_peers($peers);
}
function reorder_peers($peers) {
foreach ($peers as $key => $peer) {
if (!set_field("{$this->table}", "sortorder", $key, "id", $peer)) {
print_error('listupdatefail');
}
}
}
/**
* @param integer $id an item index.
* @return object the item that used to be the parent of the item moved.
*/
function move_item_left($id) {
$item = $this->find_item($id);
if (!isset($item->parentlist->parentitem->parentlist)) {
print_error('listcantmoveleft');
} else {
$newpeers = $this->get_items_peers($item->parentlist->parentitem->id);
if (isset($item->parentlist->parentitem->parentlist->parentitem)) {
$newparent = $item->parentlist->parentitem->parentlist->parentitem->id;
} else {
$newparent = 0; // top level item
}
if (!set_field("{$this->table}", "parent", $newparent, "id", $item->id)) {
print_error('listupdatefail');
} else {
$oldparentkey = array_search($item->parentlist->parentitem->id, $newpeers);
$neworder = array_merge(array_slice($newpeers, 0, $oldparentkey+1), array($item->id), array_slice($newpeers, $oldparentkey+1));
$this->reorder_peers($neworder);
}
}
return $item->parentlist->parentitem;
}
/**
* Make item with id $id the child of the peer that is just above it in the sort order.
*
* @param integer $id
*/
function move_item_right($id) {
$peers = $this->get_items_peers($id);
$itemkey = array_search($id, $peers);
if (!isset($peers[$itemkey-1])) {
print_error('listcantmoveright');
} else {
if (!set_field("{$this->table}", "parent", $peers[$itemkey-1], "id", $peers[$itemkey])) {
print_error('listupdatefail');
} else {
$newparent = $this->find_item($peers[$itemkey-1]);
if (isset($newparent->children)) {
$newpeers = $newparent->children->get_child_ids();
}
if ($newpeers) {
$newpeers[] = $peers[$itemkey];
$this->reorder_peers($newpeers);
}
}
}
}
/**
* process any actions.
*
* @param integer $left id of item to move left
* @param integer $right id of item to move right
* @param integer $moveup id of item to move up
* @param integer $movedown id of item to move down
* @return unknown
*/
function process_actions($left, $right, $moveup, $movedown) {
//should this action be processed by this list object?
if (!(array_key_exists($left, $this->records) || array_key_exists($right, $this->records) || array_key_exists($moveup, $this->records) || array_key_exists($movedown, $this->records))) {
return false;
}
if (!empty($left)) {
$oldparentitem = $this->move_item_left($left);
if ($this->item_is_last_on_page($oldparentitem->id)) {
// Item has jumped onto the next page, change page when we redirect.
$this->page ++;
$this->pageurl->params(array($this->pageparamname => $this->page));
}
} else if (!empty($right)) {
$this->move_item_right($right);
if ($this->item_is_first_on_page($right)) {
// Item has jumped onto the previous page, change page when we redirect.
$this->page --;
$this->pageurl->params(array($this->pageparamname => $this->page));
}
} else if (!empty($moveup)) {
$this->move_item_up_down('up', $moveup);
if ($this->item_is_first_on_page($moveup)) {
// Item has jumped onto the previous page, change page when we redirect.
$this->page --;
$this->pageurl->params(array($this->pageparamname => $this->page));
}
} else if (!empty($movedown)) {
$this->move_item_up_down('down', $movedown);
if ($this->item_is_last_on_page($movedown)) {
// Item has jumped onto the next page, change page when we redirect.
$this->page ++;
$this->pageurl->params(array($this->pageparamname => $this->page));
}
} else {
return false;
}
redirect($this->pageurl->out());
}
/**
* @param integer $itemid an item id.
* @return boolean Is the item with the given id the first top-level item on
* the current page?
*/
function item_is_first_on_page($itemid) {
return $this->page && isset($this->items[$this->firstitem]) &&
$itemid == $this->items[$this->firstitem]->id;
}
/**
* @param integer $itemid an item id.
* @return boolean Is the item with the given id the last top-level item on
* the current page?
*/
function item_is_last_on_page($itemid) {
return $this->page && isset($this->items[$this->lastitem]) &&
$itemid == $this->items[$this->lastitem]->id;
}
}
class list_item {
/**
* id of record, used if list is editable
* @var integer
*/
var $id;
/**
* name of this item, used if list is editable
* @var string
*/
var $name;
/**
* The object or string representing this item.
* @var mixed
*/
var $item;
var $fieldnamesname = 'name';
var $attributes;
var $display;
var $icons = array();
/**
* @var moodle_list
*/
var $parentlist;
/**
* Set if there are any children of this listitem.
* @var moodle_list
*/
var $children;
/**
* Constructor
* @param mixed $item fragment of html for list item or record
* @param object &$parent reference to parent of this item
* @param string $attributes attributes for li tag
* @param boolean $display whether this item is displayed. Some items may be loaded so we have a complete
* structure in memory to work with for actions but are not displayed.
* @return list_item
*/
function list_item($item, &$parent, $attributes='', $display = true) {
$this->item = $item;
if (is_object($this->item)) {
$this->id = $this->item->id;
$this->name = $this->item->{$this->fieldnamesname};
}
$this->set_parent($parent);
$this->attributes = $attributes;
$parentlistclass = get_class($parent);
$this->children =& new $parentlistclass($parent->type, $parent->attributes, $parent->editable, $parent->pageurl, 0);
$this->children->set_parent($this);
$this->display = $display;
}
/**
* Output the html just for this item. Called by to_html which adds html for children.
*
*/
function item_html($extraargs = array()) {
if (is_string($this->item)) {
$html = $this->item;
} elseif (is_object($this->item)) {
//for debug purposes only. You should create a sub class to
//properly handle the record
$html = join(', ', (array)$this->item);
}
return $html;
}
/**
* Returns html
*
* @param integer $indent
* @param array $extraargs any extra data that is needed to print the list item
* may be used by sub class.
* @return string html
*/
function to_html($indent=0, $extraargs = array()) {
if (!$this->display) {
return '';
}
$tabs = str_repeat("\t", $indent);
if (isset($this->children)) {
$childrenhtml = $this->children->to_html($indent+1, $extraargs);
} else {
$childrenhtml = '';
}
return $this->item_html($extraargs).' '.(join($this->icons, '')).(($childrenhtml !='')?("\n".$childrenhtml):'');
}
function set_icon_html($first, $last, &$lastitem) {
global $CFG;
$strmoveup = get_string('moveup');
$strmovedown = get_string('movedown');
$strmoveleft = get_string('maketoplevelitem', 'question');
$pixpath = $CFG->pixpath;
if (isset($this->parentlist->parentitem)) {
$parentitem =& $this->parentlist->parentitem;
if (isset($parentitem->parentlist->parentitem)) {
$action = get_string('makechildof', 'question', $parentitem->parentlist->parentitem->name);
} else {
$action = $strmoveleft;
}
$this->icons['left'] = $this->image_icon($action, $this->parentlist->pageurl->out_action(array('left'=>$this->id)), 'left');
} else {
$this->icons['left'] = $this->image_spacer();
}
if (!$first) {
$this->icons['up'] = $this->image_icon($strmoveup, $this->parentlist->pageurl->out_action(array('moveup'=>$this->id)), 'up');
} else {
$this->icons['up'] = $this->image_spacer();
}
if (!$last) {
$this->icons['down'] = $this->image_icon($strmovedown, $this->parentlist->pageurl->out_action(array('movedown'=>$this->id)), 'down');
} else {
$this->icons['down'] = $this->image_spacer();
}
if (!empty($lastitem)) {
$makechildof = get_string('makechildof', 'question', $lastitem->name);
$this->icons['right'] = $this->image_icon($makechildof, $this->parentlist->pageurl->out_action(array('right'=>$this->id)), 'right');
} else {
$this->icons['right'] = $this->image_spacer();
}
}
function image_icon($action, $url, $icon) {
global $CFG;
$pixpath = $CFG->pixpath;
return '
';
}
function image_spacer() {
global $CFG;
$pixpath = $CFG->pixpath;
return '';
}
/**
* Recurse down tree creating list_items, called from moodle_list::list_from_records
*
* @param array $records
* @param array $children
* @param integer $thisrecordid
*/
function create_children(&$records, &$children, $thisrecordid) {
//keys where value is $thisrecordid
$thischildren = array_keys($children, $thisrecordid);
if (count($thischildren)) {
foreach ($thischildren as $child) {
$thisclass = get_class($this);
$newlistitem =& new $thisclass($records[$child], $this->children, $this->attributes);
$this->children->add_item($newlistitem);
$newlistitem->create_children($records, $children, $records[$child]->id);
}
}
}
function set_parent(&$parent) {
$this->parentlist =& $parent;
}
}
?>