You cannot set template parameter in category-like MENU items.
-- Some templates have almost no parameters and use only template positions, but blog template (it's category layout) relies heavily on template parameters in this case you have the following alternatives:
A.
If it is a category menu item then parameters defined in category configuration (category edit form) are inherited, but for menu items "My-Items" or "Multi-Categories" MENU items they just used default values. But there is a workaround though (see B below)
B.
$this->params->set('lead_use_image', 1); $this->params->set('lead_image', 'field15'); $this->params->set('lead_width', 200); $this->params->set('lead_height', 150); $this->params->set('intro_use_image', 1); $this->params->set('intro_image', 'field15'); $this->params->set('intro_width', 150); $this->params->set('intro_height', 120);
$this->params->set('lead_num', 4);