moodle-block_mytreestudyplan/edit_form.php

<?php

require_once($CFG->dirroot.'/blocks/gradelevel/lib.php');

class block_gradelevel_edit_form extends block_edit_form {


    protected function specific_definition($mform) {
		global $CFG;
		// retrieve levelset
		$levelset = $this->block->levelset;
		
        // Section header title according to language file.
        $mform->addElement('header', 'config_header', get_string('blocksettings', 'block'));

		$skills = block_gradelevel_levelset::list_all();
		// sort by name
		usort( $skills, function( $a, $b) {
			return ( $a->getName() < $b->getName()) ? -1 : 1;
		} );

		$options = array( '-1' => get_string('edit_noneskill', 'block_gradelevel'));
		foreach($skills as $skill)
		{
			$options[$skill->getId()] = $skill->getName();
		}

        // A sample string variable with a default value.
        $mform->addElement('select', 'attached_skill', get_string('edit_pickskill', 'block_gradelevel'), $options);
	

    }

	public function set_data($defaults)
	{
		global $COURSE;

		$defaults->attached_skill = -1;
		// retrieve levelset
		$skill = block_gradelevel_levelset::find_by_course($COURSE->id);
		if(isset($skill)){
			$defaults->attached_skill = $skill->getId();
		}


		parent::set_data($defaults);
	}


	public function get_data()
	{
		$data = parent::get_data();
	
		if(isset($data))
		{
			$this->save_data($data);
		}

		return $data;
	}

	protected function save_data($data)
	{
		global $COURSE;
		// retrieve levelset

		if(isset($data->attached_skill))
		{
			$currentskill = block_gradelevel_levelset::find_by_course($COURSE->id);
			if(isset($currentskill))
			{
				$this->debug("deetaching...");
				$currentskill->detach_course($COURSE->id);
			}

			$skill = block_gradelevel_levelset::find_by_id($data->attached_skill);
			if(isset($skill)){
				$this->debug("attaching...");
				$skill->attach_course($COURSE->id);
			}
		}
	}

	private function debug($msg)
	{
		error_log($msg, 3, '/tmp/moodledevlog.log');
	}
}