bootstrap_renderer Class Reference

This class solves the problem of how to initialise $OUTPUT. More...

Public Member Functions
	__call ($method, $arguments)
	Constructor - to be used by core code only. More...
	has_started ()
	Have we started output yet? More...

Static Public Member Functions
static	early_error ($message, $moreinfourl, $link, $backtrace, $debuginfo=null, $errorcode=null)
	This function should only be called by this class, or from exception handlers. More...
static	early_error_content ($message, $moreinfourl, $link, $backtrace, $debuginfo=null)
	Returns nicely formatted error message in a div box. More...
static	early_notification ($message, $classes='notifyproblem')
	Early notification message. More...
static	early_redirect_message ($encodedurl, $message, $delay)
	Early redirection page, used before full init of $PAGE global. More...
static	plain_page ($title, $content, $meta='')
	Output basic html page. More...
static	plain_redirect_message ($encodedurl)
	Page should redirect message. More...

Protected Attributes
boolean	$initialising = false
	Handles re-entrancy. More...

Detailed Description

This class solves the problem of how to initialise $OUTPUT.

The problem is caused be two factors

1. On the one hand, we cannot be sure when output will start. In particular, an error, which needs to be displayed, could be thrown at any time.
2. On the other hand, we cannot be sure when we will have all the information necessary to correctly initialise $OUTPUT. $OUTPUT depends on the theme, which (potentially) depends on the current course, course categories, and logged in user. It also depends on whether the current page requires HTTPS.

So, it is hard to find a single natural place during Moodle script execution, which we can guarantee is the right time to initialise $OUTPUT. Instead we adopt the following strategy

1. We will initialise $OUTPUT the first time it is used.
2. If, after $OUTPUT has been initialised, the script tries to change something that $OUTPUT depends on, we throw an exception making it clear that the script did something wrong.

The only problem with that is, how do we initialise $OUTPUT on first use if, it is going to be used like $OUTPUT->somthing(...)? Well that is where this class comes in. Initially, we set up $OUTPUT = new bootstrap_renderer(). Then, when any method is called on that object, we initialise $OUTPUT, and pass the call on.

Note that this class is used before lib/outputlib.php has been loaded, so we must be careful referring to classes/functions from there, they may not be defined yet, and we must avoid fatal errors.

Copyright

2009 Tim Hunt

License

http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

Since

Moodle 2.0

Member Function Documentation

__call()

bootstrap_renderer::__call	(		$method,
			$arguments
	)

Constructor - to be used by core code only.

Parameters

string	$method	The method to call
array	$arguments	Arguments to pass to the method being called

Return values

string

early_error()

static bootstrap_renderer::early_error (   $message,   $moreinfourl,   $link,   $backtrace,   $debuginfo = null,   $errorcode = null  )

static

This function should only be called by this class, or from exception handlers.

Parameters

string	$message	error message
string	$moreinfourl	(ignored in early errors)
string	$link	(ignored in early errors)
array	$backtrace
string	$debuginfo	extra information for developers

Return values

string

early_error_content()

static bootstrap_renderer::early_error_content (   $message,   $moreinfourl,   $link,   $backtrace,   $debuginfo = null  )

static

Returns nicely formatted error message in a div box.

Parameters

string	$message	error message
string	$moreinfourl	(ignored in early errors)
string	$link	(ignored in early errors)
array	$backtrace
string	$debuginfo

Return values

string

early_notification()

static bootstrap_renderer::early_notification (   $message,   $classes = 'notifyproblem'  )

static

Early notification message.

Parameters

string	$message
string	$classes	usually notifyproblem or notifysuccess

Return values

string

early_redirect_message()

static bootstrap_renderer::early_redirect_message (   $encodedurl,   $message,   $delay  )

static

Early redirection page, used before full init of $PAGE global.

Parameters

string	$encodedurl	redirect url
string	$message	redirect message
int	$delay	time in seconds

Return values

string

redirect page

has_started()

bootstrap_renderer::has_started

(

)

Have we started output yet?

Return values

boolean

true if the header has been printed.

plain_page()

static bootstrap_renderer::plain_page (   $title,   $content,   $meta = ''  )

static

Output basic html page.

Parameters

string	$title	page title
string	$content	page content
string	$meta	meta tag

Return values

string

html page

plain_redirect_message()

static bootstrap_renderer::plain_redirect_message (   $encodedurl )

static

Page should redirect message.

Parameters

string

$encodedurl

redirect url

Return values

string

Member Data Documentation

$initialising

boolean bootstrap_renderer::$initialising = false

protected

Handles re-entrancy.

Without this, errors or debugging output that occur during the initialisation of $OUTPUT, cause infinite recursion.

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The documentation for this class was generated from the following file:

• lib/setuplib.php