Template file isn't inheriting from my block extending Mage_Core_Block_Template?

Question

I have created a module where I can add images in the admin and then they will be displayed in the front-end in the form of a banner slider.

all of my admin stuff is working fine it adds images etc etc, so I created a block (/app/code/local/Nublue/Slidemanager/Block/bannerslider.php) which consists of the following:

public function CreateSliderHtml()
{
    $html = '';
    $slideimage = Mage::getModel('nublue_slidemanager/slideimage');
    foreach ($slideimage as $slide) {
        $image = $slide->getImage();
        if ($slide->getUrl() != null || '') {
            $url = $slide->getUrl();
        }
    $html .= '<li><img src="'$image'" href="' if (isset($url)){'$url"'} 'width="600" height="400" alt=""></li>'
    }
    return $html;
}

}

and my class is called 'Nublue_Slidemanager_Block_bannerslider' and it extends 'Mage_Core_Block_Template'

in my template file

(app/design/frontend/base/default/template/Nublue_Slidemanager/bannerslider.phtml)

I have this:

            <!-- Carousel -->
            <div class="jcarousel">
                <ul>
                    <?php echo $this->CreateSliderHtml(); ?>
                </ul>
            </div>

but the echo $this->CreateSliderHtml(); gives an error

Invalid method Mage_Core_Block_Template::CreateSliderHtml(Array ( ) )

and I know the template file is being called because if I remove the php code from the template and hardcode some images then they show up.

Is there an xml file I need to edit somewhere? I thought as long as I defined where I was getting blocks and helpers and things from it would work. So to clarify I do have Nublue_Slidemanager.xml and config.xml in their correct folders

Answer 1

1. The class name must be Nublue_Slidemanager_Block_Bannerslider with capital B (also change the file name)

2. Your config.xml must define a class alias prefix for your blocks, for example:

   <global>
       <blocks>
           <slidemanager>
               <class>Nublue_Slidemanager</class>
           </slidemanager>
       </blocks>
   </global>
   

3. Wherever you integrate the block (CMS or Layout XML), you need to specify the type (i.e. the class alias):

   • CMS:

     {{block type="slidemanager/bannerslider" template="Nublue_Slidemanager/bannerslider.phtml"}}
     

   • Layout XML:

     <block name="bannerslider" type="slidemanager/bannerslider" template="Nublue_Slidemanager/bannerslider.phtml" />