Piwik\Plugin\Manager::getNumberOfActivatedPlugins PHP Method

    public function getNumberOfActivatedPlugins()
    {
        $counter = 0;
        $pluginNames = $this->getLoadedPluginsName();
        foreach ($pluginNames as $pluginName) {
            if ($this->isPluginActivated($pluginName)) {
                $counter++;
            }
        }
        return $counter;
    }