src/Controller/CRUDController.php
protected function isInPreviewMode()
    {
        return $this->admin->supportsPreviewMode()
        && ($this->isPreviewRequested()
            || $this->isPreviewApproved()
            || $this->isPreviewDeclined());
    }
protected function isInPreviewMode()
    {
        return $this->admin->supportsPreviewMode()
        && ($this->isPreviewRequested()
            || $this->isPreviewApproved()
            || $this->isPreviewDeclined());
    }
protected function isInPreviewMode ( ) { return $ this -> admin -> supportsPreviewMode ( ) && ( $ this -> isPreviewRequested ( ) || $ this -> isPreviewApproved ( ) || $ this -> isPreviewDeclined ( ) ) ; }
Returns true if the request is in the preview workflow.

That means either a preview is requested or the preview has already been shown
and it got approved/declined.

@return bool
Returns true if the request is in the preview workflow .