moodle/lib/ajax/ajaxlib.php

1415 lines
57 KiB
PHP

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Library functions to facilitate the use of JavaScript in Moodle.
*
* @package moodlecore
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
/**
* Initialise a {@link page_requirements_manager} with the bits of JavaScript that every
* Moodle page should have.
*
* @param page_requirements_manager $requires The page_requirements_manager to initialise.
*/
function setup_core_javascript(page_requirements_manager $requires) {
global $CFG;
// JavaScript should always work with $CFG->httpswwwroot rather than $CFG->wwwroot.
// Otherwise, in some situations, users will get warnings about insecure content
// on sercure pages from their web browser.
$config = array(
'wwwroot' => $CFG->httpswwwroot, // Yes, really. See above.
'sesskey' => sesskey(),
);
if (debugging('', DEBUG_DEVELOPER)) {
$config['developerdebug'] = true;
}
$requires->data_for_js('moodle_cfg', $config)->in_head();
if (debugging('', DEBUG_DEVELOPER)) {
$requires->yui_lib('logger');
}
$requires->skip_link_to('maincontent', get_string('tocontent', 'access'));
// Note that, as a short-cut, the code
// $js = "document.body.className += ' jsenabled';\n";
// is hard-coded in {@link page_requirements_manager::get_top_of_body_code)
}
/**
* This class tracks all the things that are needed by the current page.
*
* Normally, the only instance of this class you will need to work with is the
* one accessible via $PAGE->requires.
*
* Typical useage would be
* <pre>
* $PAGE->requires->css('mod/mymod/styles.css');
* $PAGE->requires->js('mod/mymod/script.js');
* $PAGE->requires->js('mod/mymod/small_but_urgent.js')->in_head();
* $PAGE->requires->js_function_call('init_mymod', array($data))->on_dom_ready();
* </pre>
*
* There are some natural restrictions on some methods. For example, {@link css()}
* can only be called before the <head> tag is output. See the comments on the
* individual methods for details.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class page_requirements_manager {
const WHEN_IN_HEAD = 0;
const WHEN_TOP_OF_BODY = 10;
const WHEN_AT_END = 20;
const WHEN_ON_DOM_READY = 30;
protected $linkedrequirements = array();
protected $stringsforjs = array();
protected $requiredjscode = array();
protected $variablesinitialised = array('mstr' => 1); // 'mstr' is special. See string_for_js.
protected $headdone = false;
protected $topofbodydone = false;
/**
* Ensure that the specified JavaScript file is linked to from this page.
*
* By default the link is put at the end of the page, since this gives best page-load performance.
*
* Even if a particular script is requested more than once, it will only be linked
* to once.
*
* @param $jsfile The path to the .js file, relative to $CFG->dirroot / $CFG->wwwroot.
* No leading slash. For example 'mod/mymod/customscripts.js';
* @param boolean $fullurl This parameter is intended for internal use only.
* However, in exceptional circumstances you may wish to use it to link
* to JavaScript on another server. For example, lib/recaptchalib.php has to
* do this. This really should only be done in exceptional circumstances. This
* may change in the future without warning.
* (If true, $jsfile is treaded as a full URL, not relative $CFG->wwwroot.)
* @return required_js The required_js object. This allows you to control when the
* link to the script is output by calling methods like {@link required_js::asap()} or
* {@link required_js::in_head()}.
*/
public function js($jsfile, $fullurl = false) {
global $CFG;
if (!$fullurl) {
// strtok is used to trim off any GET string arguments before looking for the file
if (!file_exists($CFG->dirroot . '/' . strtok($jsfile, '?'))) {
throw new coding_exception('Attept to require a JavaScript file that does not exist.', $jsfile);
}
$url = $CFG->httpswwwroot . '/' . $jsfile;
} else {
$url = $jsfile;
}
if (!isset($this->linkedrequirements[$url])) {
$this->linkedrequirements[$url] = new required_js($this, $url);
}
return $this->linkedrequirements[$url];
}
/**
* Ensure that the specified YUI library file, and all its required dependancies,
* are linked to from this page.
*
* By default the link is put at the end of the page, since this gives best page-load
* performance. Optional dependencies are not loaded automatically - if you want
* them you will need to load them first with other calls to this method.
*
* If the YUI library you ask for requires one or more CSS files, and if
* <head> has already been printed, then an exception will be thrown.
* Therefore, you are strongly advised to request all the YUI libraries you
* will need before output is started.
*
* Even if a particular library is requested more than once (perhaps as a dependancy
* of other libraries) it will only be linked to once.
*
* @param $libname the name of the YUI library you require. For example 'autocomplete'.
* @return required_yui_lib A requried_yui_lib object. This allows you to control when the
* link to the script is output by calling methods like {@link required_yui_lib::asap()} or
* {@link required_yui_lib::in_head()}.
*/
public function yui_lib($libname) {
$key = 'yui:' . $libname;
if (!isset($this->linkedrequirements[$key])) {
$this->linkedrequirements[$key] = new required_yui_lib($this, $libname);
}
return $this->linkedrequirements[$key];
}
/**
* Ensure that the specified CSS file is linked to from this page.
*
* Because stylesheet links must go in the <head> part of the HTML, you must call
* this function before {@link get_head_code()} is called. That normally means before
* the call to print_header. If you call it when it is too late, an exception
* will be thrown.
*
* Even if a particular style sheet is requested more than once, it will only
* be linked to once.
*
* @param string $stylesheet The path to the .css file, relative to
* $CFG->dirroot / $CFG->wwwroot. No leading slash. For example
* 'mod/mymod/styles.css';
* @param boolean $fullurl This parameter is intended for internal use only.
* (If true, $stylesheet is treaded as a full URL, not relative $CFG->wwwroot.)
*/
public function css($stylesheet, $fullurl = false) {
global $CFG;
if ($this->headdone) {
throw new coding_exception('Cannot require a CSS file after &lt;head> has been printed.', $stylesheet);
}
if (!$fullurl) {
if (!file_exists($CFG->dirroot . '/' . $stylesheet)) {
throw new coding_exception('Attempt to require a CSS file that does not exist.', $stylesheet);
}
$url = $CFG->httpswwwroot . '/' . $stylesheet;
} else {
$url = $stylesheet;
}
if (!isset($this->linkedrequirements[$url])) {
$this->linkedrequirements[$url] = new required_css($this, $url);
}
}
/**
* Ensure that a skip link to a given target is printed at the top of the <body>.
*
* You must call this function before {@link get_top_of_body_code()}, (if not, an exception
* will be thrown). That normally means you must call this before the call to print_header.
*
* If you ask for a particular skip link to be printed, it is then your responsibility
* to ensure that the appropraite <a name="..."> tag is printed in the body of the
* page, so that the skip link goes somewhere.
*
* Even if a particular skip link is requested more than once, only one copy of it will be output.
*
* @param $target the name of anchor this link should go to. For example 'maincontent'.
* @param $linktext The text to use for the skip link. Normally get_string('skipto', 'access', ...);
*/
public function skip_link_to($target, $linktext) {
if (!isset($this->linkedrequirements[$target])) {
$this->linkedrequirements[$target] = new required_skip_link($this, $target, $linktext);
}
}
/**
* Ensure that the specified JavaScript function is called from an inline script
* somewhere on this page.
*
* By default the call will be put in a script tag at the
* end of the page, since this gives best page-load performance.
*
* If you request that a particular function is called several times, then
* that is what will happen (unlike linking to a CSS or JS file, where only
* one link will be output).
*
* @param string $function the name of the JavaScritp function to call. Can
* be a compound name like 'YAHOO.util.Event.addListener'. Can also be
* used to create and object by using a 'function name' like 'new user_selector'.
* @param array $arguments and array of arguments to be passed to the function.
* When generating the function call, this will be escaped using json_encode,
* so passing objects and arrays should work.
* @return required_js_function_call The required_js_function_call object.
* This allows you to control when the link to the script is output by
* calling methods like {@link required_js_function_call::in_head()},
* {@link required_js_function_call::at_top_of_body()},
* {@link required_js_function_call::on_dom_ready()} or
* {@link required_js_function_call::after_delay()} methods.
*/
public function js_function_call($function, $arguments = array()) {
$requirement = new required_js_function_call($this, $function, $arguments);
$this->requiredjscode[] = $requirement;
return $requirement;
}
/**
* Make a language string available to JavaScript.
*
* All the strings will be available in a mstr object in the global namespace.
* So, for example, after a call to $PAGE->requires->string_for_js('course', 'moodle');
* then the JavaScript variable mstr.moodle.course will be 'Course', or the
* equivalent in the current language.
*
* The arguments to this function are just like the arguments to get_string
* except that $module is not optional, and there are limitations on how you
* use $a. Because each string is only stored once in the JavaScript (based
* on $identifier and $module) you cannot get the same string with two different
* values of $a. If you try, an exception will be thrown.
*
* If you do need the same string expanded with different $a values, then
* the solution is to put them in your own data structure (e.g. and array)
* that you pass to JavaScript with {@link data_for_js()}.
*
* @param string $identifier the desired string.
* @param string $module the language file to look in.
* @param mixed $a any extra data to add into the string (optional).
*/
public function string_for_js($identifier, $module, $a = NULL) {
$string = get_string($identifier, $module, $a);
if (!$module) {
throw new coding_exception('The $module parameter is required for page_requirements_manager::string_for_js.');
}
if (isset($this->stringsforjs[$module][$identifier]) && $this->stringsforjs[$module][$identifier] != $string) {
throw new coding_exception("Attempt to re-define already required string '$identifier' " .
"from lang file '$module'. Did you already ask for it with a different \$a?");
}
$this->stringsforjs[$module][$identifier] = $string;
}
/**
* Make an array of language strings available for JS
*
* This function calls the above function {@link string_for_js()} for each requested
* string in the $identifiers array that is passed to the argument for a single module
* passed in $module.
*
* <code>
* $PAGE->strings_for_js(Array('one', 'two', 'three'), 'mymod', Array('a', null, 3));
*
* // The above is identifical to calling
*
* $PAGE->string_for_js('one', 'mymod', 'a');
* $PAGE->string_for_js('two', 'mymod');
* $PAGE->string_for_js('three', 'mymod', 3);
* </code>
*
* @param array $identifiers An array of desired strings
* @param string $module The module to load for
* @param mixed $a This can either be a single variable that gets passed as extra
* information for every string or it can be an array of mixed data where the
* key for the data matches that of the identifier it is meant for.
*
*/
public function strings_for_js($identifiers, $module, $a=NULL) {
foreach ($identifiers as $key => $identifier) {
if (is_array($a) && array_key_exists($key, $a)) {
$extra = $a[$key];
} else {
$extra = $a;
}
$this->string_for_js($identifier, $module, $extra);
}
}
/**
* Make some data from PHP available to JavaScript code.
*
* For example, if you call
* <pre>
* $PAGE->requires->data_for_js('mydata', array('name' => 'Moodle'));
* </pre>
* then in JavsScript mydata.name will be 'Moodle'.
*
* You cannot call this function more than once with the same variable name
* (if you try, it will throw an exception). Your code should prepare all the
* date you want, and then pass it to this method. There is no way to change
* the value associated with a particular variable later.
*
* @param string $variable the the name of the JavaScript variable to assign the data to.
* Will probably work if you use a compound name like 'mybuttons.button[1]', but this
* should be considered an experimental feature.
* @param mixed $data The data to pass to JavaScript. This will be escaped using json_encode,
* so passing objects and arrays should work.
* @return required_data_for_js The required_data_for_js object.
* This allows you to control when the link to the script is output by
* calling methods like {@link required_data_for_js::asap()},
* {@link required_data_for_js::in_head()} or
* {@link required_data_for_js::at_top_of_body()} methods.
*/
public function data_for_js($variable, $data) {
if (isset($this->variablesinitialised[$variable])) {
throw new coding_exception("A variable called '" . $variable .
"' has already been passed ot JavaScript. You cannot overwrite it.");
}
$requirement = new required_data_for_js($this, $variable, $data);
$this->requiredjscode[] = $requirement;
$this->variablesinitialised[$variable] = 1;
return $requirement;
}
/**
* Creates a YUI event handler.
*
* @param string $id The id of the DOM element that will be listening for the event
* @param string $event A valid DOM event (click, mousedown, change etc.)
* @param string $function The name of the function to call
* @param array $arguments An optional array of argument parameters to pass to the function
* @return required_event_handler The event_handler object
*/
public function event_handler($id, $event, $function, $arguments=array()) {
$requirement = new required_event_handler($id, $event, $function, $arguments);
$this->requiredjscode[] = $requirement;
return $requirement;
}
/**
* Get the code for the linked resources that need to appear in a particular place.
* @param $when one of the WHEN_... constants.
* @return string the HTML that should be output in that place.
*/
protected function get_linked_resources_code($when) {
$output = '';
foreach ($this->linkedrequirements as $requirement) {
if (!$requirement->is_done() && $requirement->get_when() == $when) {
$output .= $requirement->get_html();
$requirement->mark_done();
}
}
return $output;
}
/**
* Get the inline JavaScript code that need to appear in a particular place.
* @param $when one of the WHEN_... constants.
* @return string the javascript that should be output in that place.
*/
protected function get_javascript_code($when, $indent = '') {
$output = '';
foreach ($this->requiredjscode as $requirement) {
if (!$requirement->is_done() && $requirement->get_when() == $when) {
$output .= $indent . $requirement->get_js_code();
$requirement->mark_done();
}
}
return $output;
}
/**
* Generate any HTML that needs to go inside the <head> tag.
*
* Normally, this method is called automatically by the code that prints the
* <head> tag. You should not normally need to call it in your own code.
*
* @return string the HTML code to to inside the <head> tag.
*/
public function get_head_code() {
setup_core_javascript($this);
$output = $this->get_linked_resources_code(self::WHEN_IN_HEAD);
$js = $this->get_javascript_code(self::WHEN_IN_HEAD);
$output .= ajax_generate_script_tag($js);
$this->headdone = true;
return $output;
}
/**
* Generate any HTML that needs to go at the start of the <body> tag.
*
* Normally, this method is called automatically by the code that prints the
* <head> tag. You should not normally need to call it in your own code.
*
* @return string the HTML code to go at the start of the <body> tag.
*/
public function get_top_of_body_code() {
$output = $this->get_linked_resources_code(self::WHEN_TOP_OF_BODY);
$js = "document.body.className += ' jsenabled';\n";
$js .= $this->get_javascript_code(self::WHEN_TOP_OF_BODY);
$output .= ajax_generate_script_tag($js);
$this->topofbodydone = true;
return $output;
}
/**
* Generate any HTML that needs to go at the end of the page.
*
* Normally, this method is called automatically by the code that prints the
* page footer. You should not normally need to call it in your own code.
*
* @return string the HTML code to to at the end of the page.
*/
public function get_end_code() {
$output = $this->get_linked_resources_code(self::WHEN_AT_END);
if (!empty($this->stringsforjs)) {
array_unshift($this->requiredjscode, new required_data_for_js($this, 'mstr', $this->stringsforjs));
}
$js = $this->get_javascript_code(self::WHEN_AT_END);
$ondomreadyjs = $this->get_javascript_code(self::WHEN_ON_DOM_READY, ' ');
if ($ondomreadyjs) {
$js .= "YAHOO.util.Event.onDOMReady(function() {\n" . $ondomreadyjs . "});\n";
}
$output .= ajax_generate_script_tag($js);
return $output;
}
/**
* @return boolean Have we already output the code in the <head> tag?
*/
public function is_head_done() {
return $this->headdone;
}
/**
* @return boolean Have we already output the code at the start of the <body> tag?
*/
public function is_top_of_body_done() {
return $this->topofbodydone;
}
}
/**
* This is the base class for all sorts of requirements. just to factor out some
* common code.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
abstract class requirement_base {
protected $manager;
protected $when;
protected $done = false;
/**
* Constructor. Normally the class and its subclasses should not be created
* directly. Client code should create them via a page_requirements_manager
* method like ->js(...).
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
*/
protected function __construct(page_requirements_manager $manager) {
$this->manager = $manager;
}
/**
* Mark that this requirement has been satisfied (that is, that the HTML
* returned by {@link get_html()} has been output.
* @return boolean has this requirement been satisfied yet? That is, has
* that the HTML returned by {@link get_html()} has been output already.
*/
public function is_done() {
return $this->done;
}
/**
* Mark that this requirement has been satisfied (that is, that the HTML
* returned by {@link get_html()} has been output.
*/
public function mark_done() {
$this->done = true;
}
/**
* Where on the page the HTML this requirement is meant to go.
* @return integer One of the {@link page_requirements_manager}::WHEN_... constants.
*/
public function get_when() {
return $this->when;
}
}
/**
* This class represents something that must be output somewhere in the HTML.
*
* Examples include links to JavaScript or CSS files. However, it should not
* necessarily be output immediately, we may have to wait for an appropriate time.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
abstract class linked_requirement extends requirement_base {
protected $url;
/**
* Constructor. Normally the class and its subclasses should not be created
* directly. Client code should create them via a page_requirements_manager
* method like ->js(...).
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $url The URL of the thing we are linking to.
*/
protected function __construct(page_requirements_manager $manager, $url) {
parent::__construct($manager);
$this->url = $url;
}
/**
* @return string the HTML needed to satisfy this requirement.
*/
abstract public function get_html();
}
/**
* A subclass of {@link linked_requirement} to represent a requried JavaScript file.
*
* You should not create instances of this class directly. Instead you should
* work with a {@link page_requirements_manager} - and probably the only
* page_requirements_manager you will ever need is the one at $PAGE->requires.
*
* The methods {@link asap()}, {@link in_head()} and {@link at_top_of_body()}
* are indented to be used as a fluid API, so you can say things like
* $PAGE->requires->js('mod/mymod/script.js')->in_head();
*
* However, by default JavaScript files are included at the end of the HTML.
* This is recommended practice because it means that the web browser will only
* start loading the javascript files after the rest of the page is loaded, and
* that gives the best performance for users.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_js extends linked_requirement {
/**
* Constructor. Normally instances of this class should not be created
* directly. Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::js()}.
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $url The URL of the JavaScript file we are linking to.
*/
public function __construct(page_requirements_manager $manager, $url) {
parent::__construct($manager, $url);
$this->when = page_requirements_manager::WHEN_AT_END;
}
public function get_html() {
return ajax_get_link_to_script($this->url);
}
/**
* Indicate that the link to this JavaScript file should be output as soon as
* possible. That is, if this requirement has already been output, this method
* does nothing. Otherwise, if the <head> tag has not yet been printed, the link
* to this script will be put in <head>. Otherwise, this method returns a
* fragment of HTML that the caller is responsible for outputting as soon as
* possible. In fact, it is recommended that you only call this function from
* an echo statement, like:
* <pre>
* echo $PAGE->requires->js(...)->asap();
* </pre>
*
* @return string The HTML required to include this JavaScript file. The caller
* is responsible for outputting this HTML promptly.
*/
public function asap() {
if ($this->is_done()) {
return;
}
if (!$this->manager->is_head_done()) {
$this->in_head();
return '';
}
$output = $this->get_html();
$this->mark_done();
return $output;
}
/**
* Indicate that the link to this JavaScript file should be output in the
* <head> section of the HTML. If it too late for this request to be
* satisfied, an exception is thrown.
*/
public function in_head() {
if ($this->is_done() || $this->when <= page_requirements_manager::WHEN_IN_HEAD) {
return;
}
if ($this->manager->is_head_done()) {
throw new coding_exception('Too late to ask for a JavaScript file to be linked to from &lt;head>.');
}
$this->when = page_requirements_manager::WHEN_IN_HEAD;
}
/**
* Indicate that the link to this JavaScript file should be output at the top
* of the <body> section of the HTML. If it too late for this request to be
* satisfied, an exception is thrown.
*/
public function at_top_of_body() {
if ($this->is_done() || $this->when <= page_requirements_manager::WHEN_TOP_OF_BODY) {
return;
}
if ($this->manager->is_top_of_body_done()) {
throw new coding_exception('Too late to ask for a JavaScript file to be linked to from the top of &lt;body>.');
}
$this->when = page_requirements_manager::WHEN_TOP_OF_BODY;
}
}
/**
* A subclass of {@link linked_requirement} to represent a requried YUI library.
*
* You should not create instances of this class directly. Instead you should
* work with a {@link page_requirements_manager} - and probably the only
* page_requirements_manager you will ever need is the one at $PAGE->requires.
*
* The methods {@link asap()}, {@link in_head()} and {@link at_top_of_body()}
* are indented to be used as a fluid API, so you can say things like
* $PAGE->requires->yui_lib('autocomplete')->in_head();
*
* This class (with the help of {@link ajax_resolve_yui_lib()}) knows about the
* dependancies between the different YUI libraries, and will include all the
* other libraries required by the one you ask for. It also knows which YUI
* libraries require css files. If the library you ask for requires CSS files,
* then you should ask for it before <head> is output, or an exception will
* be thrown.
*
* By default JavaScript files are included at the end of the HTML.
* This is recommended practice because it means that the web browser will only
* start loading the javascript files after the rest of the page is loaded, and
* that gives the best performance for users.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_yui_lib extends linked_requirement {
protected $jss = array();
/**
* Constructor. Normally instances of this class should not be created
* directly. Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::yui_lib()}.
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $libname The name of the YUI library you want. See the array
* defined in {@link ajax_resolve_yui_lib()} for a list of known libraries.
*/
public function __construct(page_requirements_manager $manager, $libname) {
parent::__construct($manager, '');
$this->when = page_requirements_manager::WHEN_AT_END;
list($jsurls, $cssurls) = ajax_resolve_yui_lib($libname);
foreach ($jsurls as $jsurl) {
$this->jss[] = $manager->js($jsurl, true);
}
foreach ($cssurls as $cssurl) {
// this might be a bit problematic because it requires yui to be
// requested before print_header() - this was not required in 1.9.x
$manager->css($cssurl, true);
}
}
public function get_html() {
// Since we create a required_js for each of our files, that will generate the HTML.
return '';
}
/**
* Indicate that the link to this YUI library file should be output as soon as
* possible. The comment above {@link required_js::asap()} applies to this method too.
*
* @return string The HTML required to include this JavaScript file. The caller
* is responsible for outputting this HTML promptly. For example, a good way to
* call this method is like
* <pre>
* echo $PAGE->requires->yui_lib(...)->asap();
* </pre>
*/
public function asap() {
if ($this->is_done()) {
return;
}
if (!$this->manager->is_head_done()) {
$this->in_head();
return '';
}
$output = '';
foreach ($this->jss as $requiredjs) {
$output .= $requiredjs->asap();
}
$this->mark_done();
return $output;
}
/**
* Indicate that the links to this YUI library should be output in the
* <head> section of the HTML. If it too late for this request to be
* satisfied, an exception is thrown.
*/
public function in_head() {
if ($this->is_done() || $this->when <= page_requirements_manager::WHEN_IN_HEAD) {
return;
}
if ($this->manager->is_head_done()) {
throw new coding_exception('Too late to ask for a YUI library to be linked to from &lt;head>.');
}
$this->when = page_requirements_manager::WHEN_IN_HEAD;
foreach ($this->jss as $requiredjs) {
$requiredjs->in_head();
}
}
/**
* Indicate that the links to this YUI library should be output in the
* <head> section of the HTML. If it too late for this request to be
* satisfied, an exception is thrown.
*/
public function at_top_of_body() {
if ($this->is_done() || $this->when <= page_requirements_manager::WHEN_TOP_OF_BODY) {
return;
}
if ($this->manager->is_top_of_body_done()) {
throw new coding_exception('Too late to ask for a YUI library to be linked to from the top of &lt;body>.');
}
$this->when = page_requirements_manager::WHEN_TOP_OF_BODY;
foreach ($this->jss as $requiredjs) {
$output .= $requiredjs->at_top_of_body();
}
}
}
/**
* A subclass of {@link linked_requirement} to represent a required CSS file.
* Of course, all links to CSS files must go in the <head> section of the HTML.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_css extends linked_requirement {
/**
* Constructor. Normally instances of this class should not be created directly.
* Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::css()}
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $url The URL of the CSS file we are linking to.
*/
public function __construct(page_requirements_manager $manager, $url) {
parent::__construct($manager, $url);
$this->when = page_requirements_manager::WHEN_IN_HEAD;
}
public function get_html() {
return '<link rel="stylesheet" type="text/css" href="' . $this->url . '" />' . "\n";;
}
}
/**
* A subclass of {@link linked_requirement} to represent a skip link.
* A skip link is a concept from accessibility. You have some links like
* 'Skip to main content' linking to an #maincontent anchor, at the start of the
* <body> tag, so that users using assistive technologies like screen readers
* can easily get to the main content without having to work their way through
* any navigation, blocks, etc. that comes before it in the HTML.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_skip_link extends linked_requirement {
protected $linktext;
/**
* Constructor. Normally instances of this class should not be created directly.
* Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::yui_lib()}.
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $target the name of the anchor in the page we are linking to.
* @param string $linktext the test to use for the link.
*/
public function __construct(page_requirements_manager $manager, $target, $linktext) {
parent::__construct($manager, $target);
$this->when = page_requirements_manager::WHEN_TOP_OF_BODY;
$this->linktext = $linktext;
}
public function get_html() {
return '<a class="skip" href="#' . $this->url . '">' . $this->linktext . "</a>\n";
}
}
/**
* This is the base class for requirements that are JavaScript code.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
abstract class required_js_code extends requirement_base {
/**
* Constructor.
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
*/
protected function __construct(page_requirements_manager $manager) {
parent::__construct($manager);
$this->when = page_requirements_manager::WHEN_AT_END;
}
/**
* @return string the JavaScript code needed to satisfy this requirement.
*/
abstract public function get_js_code();
/**
* Indicate that the link to this JavaScript file should be output as soon as
* possible. That is, if this requirement has already been output, this method
* does nothing. Otherwise, if the <head> tag has not yet been printed, the link
* to this script will be put in <head>. Otherwise, this method returns a
* fragment of HTML that the caller is responsible for outputting as soon as
* possible. In fact, it is recommended that you only call this function from
* an echo statement, like:
* <pre>
* echo $PAGE->requires->js(...)->asap();
* </pre>
*
* @return string The HTML required to include this JavaScript file. The caller
* is responsible for outputting this HTML promptly.
*/
public function asap() {
if ($this->is_done()) {
return;
}
if (!$this->manager->is_head_done()) {
$this->in_head();
return '';
}
$js = $this->get_js_code();
$output = ajax_generate_script_tag($js);
$this->mark_done();
return $output;
}
/**
* Indicate that the link to this JavaScript file should be output in the
* <head> section of the HTML. If it too late for this request to be
* satisfied, an exception is thrown.
*/
public function in_head() {
if ($this->is_done() || $this->when <= page_requirements_manager::WHEN_IN_HEAD) {
return;
}
if ($this->manager->is_head_done()) {
throw new coding_exception('Too late to ask for some JavaScript code to be output in &lt;head>.');
}
$this->when = page_requirements_manager::WHEN_IN_HEAD;
}
/**
* Indicate that the link to this JavaScript file should be output at the top
* of the <body> section of the HTML. If it too late for this request to be
* satisfied, an exception is thrown.
*/
public function at_top_of_body() {
if ($this->is_done() || $this->when <= page_requirements_manager::WHEN_TOP_OF_BODY) {
return;
}
if ($this->manager->is_top_of_body_done()) {
throw new coding_exception('Too late to ask for some JavaScript code to be output at the top of &lt;body>.');
}
$this->when = page_requirements_manager::WHEN_TOP_OF_BODY;
}
}
/**
* This class represents a JavaScript function that must be called from the HTML
* page. By default the call will be made at the end of the page, but you can
* chage that using the {@link asap()}, {@link in_head()}, etc. methods.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_js_function_call extends required_js_code {
protected $function;
protected $arguments;
protected $delay = 0;
/**
* Constructor. Normally instances of this class should not be created directly.
* Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::js_function_call()}.
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $function the name of the JavaScritp function to call.
* Can be a compound name like 'YAHOO.util.Event.addListener'.
* @param array $arguments and array of arguments to be passed to the function.
* When generating the function call, this will be escaped using json_encode,
* so passing objects and arrays should work.
*/
public function __construct(page_requirements_manager $manager, $function, $arguments) {
parent::__construct($manager);
$this->function = $function;
$this->arguments = $arguments;
}
public function get_js_code() {
$quotedargs = array();
foreach ($this->arguments as $arg) {
$quotedargs[] = json_encode($arg);
}
$js = $this->function . '(' . implode(', ', $quotedargs) . ');';
if ($this->delay) {
$js = 'setTimeout(function() { ' . $js . ' }, ' . ($this->delay * 1000) . ');';
}
return $js . "\n";
}
/**
* Indicate that this function should be called in YUI's onDomReady event.
*
* Not that this is probably not necessary most of the time. Just having the
* function call at the end of the HTML should normally be sufficient.
*/
public function on_dom_ready() {
if ($this->is_done() || $this->when < page_requirements_manager::WHEN_AT_END) {
return;
}
$this->manager->yui_lib('event');
$this->when = page_requirements_manager::WHEN_ON_DOM_READY;
}
/**
* Indicate that this function should be called a certain number of seconds
* after the page has finished loading. (More exactly, a number of seconds
* after the onDomReady event fires.)
*
* @param integer $seconds the number of seconds delay.
*/
public function after_delay($seconds) {
if ($seconds) {
$this->on_dom_ready();
}
$this->delay = $seconds;
}
}
/**
* This class represents some data from PHP that needs to be made available in a
* global JavaScript variable. By default the data will be output at the end of
* the page, but you can chage that using the {@link asap()}, {@link in_head()}, etc. methods.
*
* @copyright 2009 Tim Hunt
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_data_for_js extends required_js_code {
protected $variable;
protected $data;
/**
* Constructor. Normally the class and its subclasses should not be created directly.
* Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::data_for_js()}.
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $variable the the name of the JavaScript variable to assign the data to.
* Will probably work if you use a compound name like 'mybuttons.button[1]', but this
* should be considered an experimental feature.
* @param mixed $data The data to pass to JavaScript. This will be escaped using json_encode,
* so passing objects and arrays should work.
*/
public function __construct(page_requirements_manager $manager, $variable, $data) {
parent::__construct($manager);
$this->variable = $variable;
$this->data = json_encode($data);
// json_encode immediately, so that if $data is an object (and therefore was
// passed in by reference) we get the data at the time the call was made, and
// not whatever the data happened to be when this is output.
}
public function get_js_code() {
$prefix = 'var ';
if (strpos($this->variable, '.') || strpos($this->variable, '[')) {
$prefix = '';
}
return $prefix . $this->variable . ' = ' . $this->data . ";\n";
}
}
/**
* This class represents a Javascript event handler, listening for a
* specific Event to occur on a DOM element identified by a given id.
* By default the data will be output at the end of the page, but you
* can change that using the {@link asap()}, {@link in_head()}, etc. methods.
*
* @copyright 2009 Nicolas Connault
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @since Moodle 2.0
*/
class required_event_handler extends required_js_code {
protected $id;
protected $event;
protected $function;
protected $args = array();
/**
* Constructor. Normally the class and its subclasses should not be created directly.
* Client code should create them via the page_requirements_manager
* method {@link page_requirements_manager::data_for_js()}.
*
* @param page_requirements_manager $manager the page_requirements_manager we are associated with.
* @param string $id The id of the DOM element that will be listening for the event
* @param string $event A valid DOM event (click, mousedown, change etc.)
* @param string $function The name of the function to call
* @param array $arguments An optional array of argument parameters to pass to the function
*/
public function __construct(page_requirements_manager $manager, $id, $event, $function, $args=array()) {
$manager->requires->yui_lib('event');
parent::__construct($manager);
$this->id = $id;
$this->event = $event;
$this->function = $function;
$this->args = $args;
}
public function get_js_code() {
$output = "YAHOO.util.Event.addListener($this->id, '$this->event', $this->function";
if (!empty($this->args)) {
$output .= ', ' . json_encode($this->args);
}
return $output . ");\n";
}
}
/**
* Generate a script tag containing the the specified code.
*
* @param string $js the JavaScript code
* @return string HTML, the code wrapped in <script> tags.
*/
function ajax_generate_script_tag($js) {
if ($js) {
return '<script type="text/javascript">' . "\n//<![CDATA[\n" .
$js . "//]]>\n</script>\n";
} else {
return '';
}
}
/**
* Given the name of a YUI library, return a list of the .js and .css files that
* it requries.
*
* This method takes note of the $CFG->useexternalyui setting.
*
* If $CFG->debug is set to DEBUG_DEVELOPER then this method will return links to
* the -debug version of the YUI files, otherwise it will return links to the -min versions.
*
* @param string $libname the name of a YUI library, for example 'autocomplete'.
* @return array with two elementes. The first is an array of the JavaScript URLs
* that must be loaded to make this library work, in the order they should be
* loaded. The second element is a (possibly empty) list of CSS files that
* need to be loaded.
*/
function ajax_resolve_yui_lib($libname) {
global $CFG;
// Note, we always use yahoo-dom-event, even if we are only asked for part of it.
// because another part of the code may later ask for other bits. It is easier, and
// not very inefficient, just to always use (and get browsers to cache) the combined file.
static $translatelist = array(
'yahoo' => 'yahoo-dom-event',
'animation' => array('yahoo-dom-event', 'animation'),
'autocomplete' => array(
'js' => array('yahoo-dom-event', 'datasource', 'autocomplete'),
'css' => array('autocomplete/assets/skins/sam/autocomplete.css')),
'button' => array(
'js' => array('yahoo-dom-event', 'element', 'button'),
'css' => array('button/assets/skins/sam/button.css')),
'calendar' => array(
'js' => array('yahoo-dom-event', 'calendar'),
'css' => array('calendar/assets/skins/sam/calendar.css')),
'carousel' => array(
'js' => array('yahoo-dom-event', 'element', 'carousel'),
'css' => array('carousel/assets/skins/sam/carousel.css')),
'charts' => array('yahoo-dom-event', 'element', 'datasource', 'json', 'charts'),
'colorpicker' => array(
'js' => array('utilities', 'slider', 'colorpicker'),
'css' => array('colorpicker/assets/skins/sam/colorpicker.css')),
'connection' => array('yahoo-dom-event', 'connection'),
'container' => array(
'js' => array('yahoo-dom-event', 'container'),
'css' => array('container/assets/skins/sam/container.css')),
'cookie' => array('yahoo-dom-event', 'cookie'),
'datasource' => array('yahoo-dom-event', 'datasource'),
'datatable' => array(
'js' => array('yahoo-dom-event', 'element', 'datasource', 'datatable'),
'css' => array('datatable/assets/skins/sam/datatable.css')),
'dom' => 'yahoo-dom-event',
'dom-event' => 'yahoo-dom-event',
'dragdrop' => array('yahoo-dom-event', 'dragdrop'),
'editor' => array(
'js' => array('yahoo-dom-event', 'element', 'container', 'menu', 'button', 'editor'),
'css' => array('assets/skins/sam/skin.css')),
'element' => array('yahoo-dom-event', 'element'),
'event' => 'yahoo-dom-event',
'get' => array('yahoo-dom-event', 'get'),
'history' => array('yahoo-dom-event', 'history'),
'imagecropper' => array(
'js' => array('yahoo-dom-event', 'dragdrop', 'element', 'resize', 'imagecropper'),
'css' => array('assets/skins/sam/resize.css', 'assets/skins/sam/imagecropper.css')),
'imageloader' => array('yahoo-dom-event', 'imageloader'),
'json' => array('yahoo-dom-event', 'json'),
'layout' => array(
'js' => array('yahoo-dom-event', 'dragdrop', 'element', 'layout'),
'css' => array('reset-fonts-grids/reset-fonts-grids.css', 'assets/skins/sam/layout.css')),
'logger' => array(
'js' => array('yahoo-dom-event', 'logger'),
'css' => array('logger/assets/skins/sam/logger.css')),
'menu' => array(
'js' => array('yahoo-dom-event', 'container', 'menu'),
'css' => array('menu/assets/skins/sam/menu.css')),
'paginator' => array(
'js' => array('yahoo-dom-event', 'element', 'paginator'),
'css' => array('paginator/assets/skins/sam/paginator.css')),
'profiler' => array('yahoo-dom-event', 'profiler'),
'profilerviewer' => array('yuiloader-dom-event', 'element', 'profiler', 'profilerviewer'),
'resize' => array(
'js' => array('yahoo-dom-event', 'dragdrop', 'element', 'resize'),
'css' => array('assets/skins/sam/resize.css')),
'selector' => array('yahoo-dom-event', 'selector'),
'simpleeditor' => array(
'js' => array('yahoo-dom-event', 'element', 'container', 'simpleeditor'),
'css' => array('assets/skins/sam/skin.css')),
'slider' => array('yahoo-dom-event', 'gragdrop', 'slider'),
'stylesheet' => array('yahoo-dom-event', 'stylesheet'),
'tabview' => array(
'js' => array('yahoo-dom-event', 'element', 'tabview'),
'css' => array('assets/skins/sam/skin.css')),
'treeview' => array(
'js' => array('yahoo-dom-event', 'treeview'),
'css' => array('treeview/assets/skins/sam/treeview.css')),
'uploader' => array('yahoo-dom-event', 'element', 'uploader'),
'utilities' => array('yahoo-dom-event', 'connection', 'animation', 'dragdrop', 'element', 'get'),
'yuiloader' => 'yuiloader',
'yuitest' => array(
'js' => array('yahoo-dom-event', 'logger', 'yuitest'),
'css' => array('logger/assets/logger.css', 'yuitest/assets/testlogger.css')),
);
if (!isset($translatelist[$libname])) {
throw new coding_exception('Unknown YUI library ' . $libname);
}
$data = $translatelist[$libname];
if (!is_array($data)) {
$jsnames = array($data);
$cssfiles = array();
} else if (isset($data['js']) && isset($data['css'])) {
$jsnames = $data['js'];
$cssfiles = $data['css'];
} else {
$jsnames = $data;
$cssfiles = array();
}
$debugging = debugging('', DEBUG_DEVELOPER);
if ($debugging) {
$suffix = '-debug.js';
} else {
$suffix = '-min.js';
}
$libpath = $CFG->httpswwwroot . '/lib/yui/';
$externalyui = !empty($CFG->useexternalyui);
if ($externalyui) {
include($CFG->libdir.'/yui/version.php'); // Sets $yuiversion.
$libpath = 'http://yui.yahooapis.com/' . $yuiversion . '/build/';
}
$jsurls = array();
foreach ($jsnames as $js) {
if ($js == 'yahoo-dom-event') {
if ($debugging) {
$jsurls[] = $libpath . 'yahoo/yahoo' . $suffix;
$jsurls[] = $libpath . 'dom/dom' . $suffix;
$jsurls[] = $libpath . 'event/event' . $suffix;
} else {
$jsurls[] = $libpath . $js . '/' . $js . '.js';
}
} else {
$jsurls[] = $libpath . $js . '/' . $js . $suffix;
}
}
$cssurls = array();
foreach ($cssfiles as $css) {
$cssurls[] = $libpath . $css;
}
return array($jsurls, $cssurls);
}
/**
* Return the HTML required to link to a JavaScript file.
* @param $url the URL of a JavaScript file.
* @return string the required HTML.
*/
function ajax_get_link_to_script($url) {
return '<script type="text/javascript" src="' . $url . '"></script>' . "\n";
}
/**
* Returns whether ajax is enabled/allowed or not.
*/
function ajaxenabled($browsers = array()) {
global $CFG, $USER;
if (!empty($browsers)) {
$valid = false;
foreach ($browsers as $brand => $version) {
if (check_browser_version($brand, $version)) {
$valid = true;
}
}
if (!$valid) {
return false;
}
}
$ie = check_browser_version('MSIE', 6.0);
$ff = check_browser_version('Gecko', 20051106);
$op = check_browser_version('Opera', 9.0);
$sa = check_browser_version('Safari', 412);
if (!$ie && !$ff && !$op && !$sa) {
/** @see http://en.wikipedia.org/wiki/User_agent */
// Gecko build 20051107 is what is in Firefox 1.5.
// We still have issues with AJAX in other browsers.
return false;
}
if (!empty($CFG->enableajax) && (!empty($USER->ajax) || !isloggedin())) {
return true;
} else {
return false;
}
}
/**
* Used to create view of document to be passed to JavaScript on pageload.
* We use this class to pass data from PHP to JavaScript.
*/
class jsportal {
var $currentblocksection = null;
var $blocks = array();
/**
* Takes id of block and adds it
*/
function block_add($id, $hidden=false){
$hidden_binary = 0;
if ($hidden) {
$hidden_binary = 1;
}
$this->blocks[count($this->blocks)] = array($this->currentblocksection, $id, $hidden_binary);
}
/**
* Prints the JavaScript code needed to set up AJAX for the course.
*/
function print_javascript($courseid, $return=false) {
global $CFG, $USER, $OUTPUT;
$blocksoutput = $output = '';
for ($i=0; $i<count($this->blocks); $i++) {
$blocksoutput .= "['".$this->blocks[$i][0]."',
'".$this->blocks[$i][1]."',
'".$this->blocks[$i][2]."']";
if ($i != (count($this->blocks) - 1)) {
$blocksoutput .= ',';
}
}
$output .= "<script type=\"text/javascript\">\n";
$output .= " main.portal.id = ".$courseid.";\n";
$output .= " main.portal.blocks = new Array(".$blocksoutput.");\n";
$output .= " main.portal.strings['wwwroot']='".$CFG->wwwroot."';\n";
$output .= " main.portal.strings['marker']='".get_string('markthistopic', '', '_var_')."';\n";
$output .= " main.portal.strings['marked']='".get_string('markedthistopic', '', '_var_')."';\n";
$output .= " main.portal.strings['hide']='".get_string('hide')."';\n";
$output .= " main.portal.strings['hidesection']='".get_string('hidesection', '', '_var_')."';\n";
$output .= " main.portal.strings['show']='".get_string('show')."';\n";
$output .= " main.portal.strings['delete']='".get_string('delete')."';\n";
$output .= " main.portal.strings['move']='".get_string('move')."';\n";
$output .= " main.portal.strings['movesection']='".get_string('movesection', '', '_var_')."';\n";
$output .= " main.portal.strings['moveleft']='".get_string('moveleft')."';\n";
$output .= " main.portal.strings['moveright']='".get_string('moveright')."';\n";
$output .= " main.portal.strings['update']='".get_string('update')."';\n";
$output .= " main.portal.strings['groupsnone']='".get_string('groupsnone')."';\n";
$output .= " main.portal.strings['groupsseparate']='".get_string('groupsseparate')."';\n";
$output .= " main.portal.strings['groupsvisible']='".get_string('groupsvisible')."';\n";
$output .= " main.portal.strings['clicktochange']='".get_string('clicktochange')."';\n";
$output .= " main.portal.strings['deletecheck']='".get_string('deletecheck','','_var_')."';\n";
$output .= " main.portal.strings['resource']='".get_string('resource')."';\n";
$output .= " main.portal.strings['activity']='".get_string('activity')."';\n";
$output .= " main.portal.strings['sesskey']='".sesskey()."';\n";
$output .= " main.portal.icons['spacerimg']='".$OUTPUT->old_icon_url('spaces')."';\n";
$output .= " main.portal.icons['marker']='".$OUTPUT->old_icon_url('i/marker')."';\n";
$output .= " main.portal.icons['ihide']='".$OUTPUT->old_icon_url('i/hide')."';\n";
$output .= " main.portal.icons['move_2d']='".$OUTPUT->old_icon_url('i/move_2d')."';\n";
$output .= " main.portal.icons['show']='".$OUTPUT->old_icon_url('t/show')."';\n";
$output .= " main.portal.icons['hide']='".$OUTPUT->old_icon_url('t/hide')."';\n";
$output .= " main.portal.icons['delete']='".$OUTPUT->old_icon_url('t/delete')."';\n";
$output .= " main.portal.icons['groupn']='".$OUTPUT->old_icon_url('t/groupn')."';\n";
$output .= " main.portal.icons['groups']='".$OUTPUT->old_icon_url('t/groups')."';\n";
$output .= " main.portal.icons['groupv']='".$OUTPUT->old_icon_url('t/groupv')."';\n";
if (right_to_left()) {
$output .= " main.portal.icons['backwards']='".$OUTPUT->old_icon_url('t/right')."';\n";
$output .= " main.portal.icons['forwards']='".$OUTPUT->old_icon_url('t/left')."';\n";
} else {
$output .= " main.portal.icons['backwards']='".$OUTPUT->old_icon_url('t/left')."';\n";
$output .= " main.portal.icons['forwards']='".$OUTPUT->old_icon_url('t/right')."';\n";
}
$output .= " onloadobj.load();\n";
$output .= " main.process_blocks();\n";
$output .= "</script>";
if ($return) {
return $output;
} else {
echo $output;
}
}
}
?>