Use multiple templates dependent on host name in SF1

config_handlers.yml

modules/*/config/view.yml:
  class:    dcmsViewConfigHandler

myViewConfigHandler.php

<?php

class myViewConfigHandler extends sfViewConfigHandler
{
  /**
   * Adds a layout statement statement to the data.
   *
   * @param string $viewName The view name
   *
   * @return string The PHP statement
   */
  protected function addLayout($viewName = '')
  {
    // true if the user set 'has_layout' to true or set a 'layout' name for this specific action
    $hasLocalLayout = isset($this->yamlConfig[$viewName]['layout']) || (isset($this->yamlConfig[$viewName]) && array_key_exists('has_layout', $this->yamlConfig[$viewName]));

    // the layout value
    $layout = $this->getConfigValue('has_layout', $viewName) ? $this->getConfigValue('layout', $viewName) : false;

    // the user set a decorator in the action
    $data = <<<EOF
  if (null !== \$layout = sfConfig::get('symfony.view.'.\$this->moduleName.'_'.\$this->actionName.'_layout'))
  {
    \$this->setDecoratorTemplate(false === \$layout ? false : \$layout.\$this->getExtension());
  }
EOF;

    if ($hasLocalLayout)
    {
      // the user set a decorator in view.yml for this action
      // This is the important part
      $data .= <<<EOF

  else
  {
    \$site = \$_SERVER['HTTP_HOST'];
    \$mlayout = \$site;

    \$this->setDecoratorTemplate('' == \$mlayout ? false : \$mlayout.\$this->getExtension());
  }

EOF;
    }
    else
    {
      // no specific configuration
      // set the layout to the 'all' view.yml value except if:
      //   * the decorator template has already been set by "someone" (via view.configure_format for example)
      //   * the request is an XMLHttpRequest request
      $data .= <<<EOF

  else if (null === \$this->getDecoratorTemplate() && !\$this->context->getRequest()->isXmlHttpRequest())
  {
    \$site = \$_SERVER['HTTP_HOST'];
    \$mlayout = \$site;

    \$this->setDecoratorTemplate('' == \$mlayout ? false : \$mlayout.\$this->getExtension());
  }

EOF;
    }

    return $data;
  }
}