Navigation buttons (for Moodle 2.x)

This block adds navigation buttons (first/previous/next/etc.) to the bottom of each activity/resource page in a course.
It is based on an idea from Penny Mondani: http://pennymondani.com
Thanks also to the US company that sponsored the development, who wish to remain anonymous.

Changes:

2014-07-06 - Added 'text button' option, checked M2.7 compatibility, minor styling tweak
2013-11-19 - Moodle 2.6 compatibility fixes
2013-10-21 - Extra note in README about custom / 3rd-party themes
2013-05-22 - Minor Moodle 2.5 compatibility fixes
2013-03-15 - Fixed PHP 5.3 compatibility issue
2012-12-30 - Fixed settings page in Moodle 2.4
2012-12-07 - Now compatible with Moodle 2.4
2012-07-02 - Confirmed all working fine with Moodle 2.3
2012-02-28 - New global settings to control which activities have navbuttons on them and when they should be shown

Installation:

1. Download the file and unzip it somewhere convenient.
2. On your server, in the 'blocks' folder, create a subfolder called 'navbuttons'
3. Upload all the files inside the 'davosmith-moodle-navbuttons-???????' folder to this new 'navbuttons' folder on your server.
4. Log in to your Moodle site as an administrator and click on the 'Notifications' option in the Admin settings block.
5. You need to edit one Moodle core file to make this work:

Find the file 'moodle/lib/outputrenderers.php'.
Find the line:

$output = $this->container_end_all(true);

(It should only be there once, shortly after the line 'public function footer() {')
REPLACE the line you found with this code:

require_once($CFG->dirroot.'/blocks/navbuttons/footer.php');  // Add this line to enable the navigation buttons
$output = draw_navbuttons().$this->container_end_all(true);   // Change this line to enable the navigation buttons

6. Add the block to a course (turn editing on, select 'Navigation Buttons' from the 'Blocks - Add' menu)
7. Customise the button appearance by clicking on 'Edit the Navigation Button settings' in the newly created block.
8. Check the message at the bottom of the screen (under the 'Save changes' button) - it should read "Navbuttons self-test: required core modifications have been completed successfully". If not, then go back to step 5 above and check carefully.

Note: The block is only visible to users who are able to edit courses modules. Deleting the block will remove the navigation buttons (they can also be disabled through the settings).

== Using with custom / 3rd-part themes ==

If the theme you are using overrides the page footer code (Essential theme is known to do this), then you will have to make some slightly different core changes in step 5.

Open up: theme/[theme name]/renderer.php
Look for a function called 'footer()'.
If you are lucky, you should be able to repeat the changes from step 5 within this function (I've had reports that this works with Essential theme).
If not, then you will have to try and figure out where best to put the code within the 'footer()' function.

== Any Problems ==

If you have a problem with the buttons not showing up as expected, then try the following:

1. Click on the 'Edit the Navigation Buttons settings' link in the block and scroll down to the bottom.
Check that the message reads 'Navbuttons self-test: required core modifications have been completed successfully'.
If not, go back up to step 5 of the installation instructions.

2. Visit 'Site admin > Plugins > Blocks > Navigation buttons' and check that the buttons are enabled for the activity
type you are viewing (the settings are 'Always show', 'Never show' or 'Show when complete', some activities have extra,
custom rules).

3. Visit a page that should have the navigation buttons on it, then use your browsers 'view source' menu option to see
the HTML code for the page. Search for '<!-- Navbuttons start -->' (without quotes). Look to see what message is displayed
after this line (and before '<!-- Navbuttons end -->'). It will be one of:
* Front page - navigation buttons are not displayed on the front page course
* No settings - the block has not been added to this course
* Not enabled - the block has been added, but the buttons are disabled in the settings
* No course module - this page is not part of a course module (activity/resource) within a course
* Activity not ready for navbuttons - the global settings mean that the buttons are not displayed for this activity (or
they will not be displayed until this activity is complete).

If you have any questions about this block, suggestions for improvement, drop me an email at:
moodle@davosmith.co.uk