Magento - move block from right to left

Question

Not sure why this is so difficult. If I understand THIS correctly, I should be able to swiftly accomplish my goals... But no joy.

So - I'm building my first theme, and still getting my head around layout...

I'm working specifically on the Catalog Product View page, and am converting this page from a right column layout to a left column layout. I simply want to move the blocks from the right into the left.

In the default catalog.xml, product_list_related is defined:

     </catalog_product_view> 
     //...

     <reference name="right">
            <block type="catalog/product_list_related" name="catalog.product.related" before="-" template="catalog/product/list/related.phtml"/>
        </reference>
    </catalog_product_view>

In my local.xml, I'm simply trying to move this block:

    <layout>

    // bunch other page directives

   <catalog_product_view>
        <reference name="root">
            <action method="setTemplate"><template>page/2columns-left.phtml</template></action>
        </reference>

        <reference name="right">
            <action method="unsetChild"><name>catalog.product.related</name></action>
        </reference>

        <reference name="left">
            <action method="insert"><blockName>catalog.product.related</blockName></action>

            // note that that "catalog.leftnav" gets inserted as expected
            <block type="catalog/layer_view" name="catalog.leftnav" after="-" template="catalog/layer/view.phtml"/>
        </reference>

    </catalog_product_view>

    </layout>

As noted - inserting catalog.leftnav works as expected, so I'm assuming everything else is set up correctly. The target block renders as expected if I leave the template and other directives unchanged, which tells me that the block should render once its been properly unset and inserted...

This is driving me nuts... but what else is new with Magento.

Cheers -

b[]x

UPDATE

Because I simply can not get a local.xml override to work, I'm just falling back on a modified catalog.xml. I'm a reasonably smart guy... it worries me that I can't get this to work (and that magento just silently fails, whatever the case ) - but I can't waste anymore time dicking around with this stupid issue.

Moving on.

UPDATE, again. 

Spent some time, now, working in magento and getting more familiar with its complexities. I came back to this issue today as I need to get my local.xml working right.

I really don't know what I had wrong, but this set of directives finally worked.

        <reference name="right">
                <action method="unsetChild">
                    <alias>catalog.product.related</alias>
                </action>
        </reference>

        <reference name="left">
                <action method="insert">
                    <block>catalog.product.related</block>
                </action>
        </reference>

A key point I'll make note of for others dealing with this:

Layout xml directives call available methods within magento classes. In this case, Page.xmls "Left" block is of type Mage_Core_Block_Text, which inherits from Mage_Core_Block_Abstract which contains the methods unsetChild and insert.

from Mage_Core_Block_Abstract :

/**
     * Unset child block
     *
     * @param  string $alias
     * @return Mage_Core_Block_Abstract
     */
    public function unsetChild($alias)
    {
        if (isset($this->_children[$alias])) {
            unset($this->_children[$alias]);
        }

        if (!empty($this->_sortedChildren)) {
            $key = array_search($alias, $this->_sortedChildren);
            if ($key !== false) {
                unset($this->_sortedChildren[$key]);
            }
        }

        return $this;
    }

and

  /**
     * Insert child block
     *
     * @param   Mage_Core_Block_Abstract|string $block
     * @param   string $siblingName
     * @param   boolean $after
     * @param   string $alias
     * @return  object $this
     */
    public function insert($block, $siblingName = '', $after = false, $alias = '')
    {
        if (is_string($block)) {
            $block = $this->getLayout()->getBlock($block);
        }
        if (!$block) {
            /*
             * if we don't have block - don't throw exception because
             * block can simply removed using layout method remove
             */
            //Mage::throwException(Mage::helper('core')->__('Invalid block name to set child %s: %s', $alias, $block));
            return $this;
        }
        if ($block->getIsAnonymous()) {
            $this->setChild('', $block);
            $name = $block->getNameInLayout();
        } elseif ('' != $alias) {
            $this->setChild($alias, $block);
            $name = $block->getNameInLayout();
        } else {
            $name = $block->getNameInLayout();
            $this->setChild($name, $block);
        }

        if ($siblingName === '') {
            if ($after) {
                array_push($this->_sortedChildren, $name);
            } else {
                array_unshift($this->_sortedChildren, $name);
            }
        } else {
            $key = array_search($siblingName, $this->_sortedChildren);
            if (false !== $key) {
                if ($after) {
                    $key++;
                }
                array_splice($this->_sortedChildren, $key, 0, $name);
            } else {
                if ($after) {
                    array_push($this->_sortedChildren, $name);
                } else {
                    array_unshift($this->_sortedChildren, $name);
                }
            }

            $this->_sortInstructions[$name] = array($siblingName, (bool)$after, false !== $key);
        }

        return $this;
    }

Local xml parameters are important, then, not in name (specifically), but in order ie:

<reference name="left">
                <action method="insert">
                    <block>catalog.product.related</block>
                    <siblingName>catalog.leftnav</siblingName>
                    <after>1</after>
                    <alias>catalog_product_related</alias>
                </action>
        </reference>

Ultimately, this makes local.xml a really powerful method of manipulating the system, but if you are unfamiliar with it and the magento system, get ready for weeks or months of work to really get your head around it.

Cheers

---

Yet another update

I've run into the problem several times now, where a block I want to move has been removed. This is a problem, as any block that has been removed from layout is nuked forever.

However, with Alan Storm's very handy Unremove Plugin you can undo whats been done:

<checkout_onepage_index>
    <x-unremove name="left" />
    <reference name="right">
        <action method="unsetChild">
            <alias>checkout.progress.wrapper</alias>
        </action>
    </reference>
    <reference name="left">
        <action method="insert">
            <block>checkout.progress.wrapper</block>
        </action>
    </reference>
</checkout_onepage_index>

It manages this feat by watching the layout object, and building a list of removed blocks, which can be later referenced.

Nice!

Answer 1

This is a dusty thread now, but for the record, this is the final answer I went with.

<reference name="right">
    <action method="unsetChild">
        <alias>checkout.progress.wrapper</alias>
    </action>
</reference>
<reference name="left">
    <action method="insert">
        <block>checkout.progress.wrapper</block>
    </action>
</reference>

Magento recommends including this in your local.xml, and it has proved an effective technique.

Answer 2

I would do it this way: In your local.xml under e.g.

<reference name="right"></reference>

you remove the blocks, e.g.:

<remove name="right.poll">

and then you add the blocks in

<reference name="left"></reference>

Answer 3

I think the best answer to modify Magento layouts is given on Classyllama.com

http://www.classyllama.com/development/magento-development/the-better-way-to-modify-magento-layout

When you use the remove tag, it removes any blocks with the specified name from the entire layout, regardless of the context. So, if I remove right.newsletter in the context and that name is used in say the context, then both blocks will be removed. Because remove operates on the global context, you can only remove an element once. Since is being called in catalogsearch.xml, we have to unset it, or else we'll get an error.

<action method="unsetChild"><name>right.newsletter</name></action>;

Answer 4

Copying base/default to a local theme is a horrible idea. Every update to a core theme file on a Magento version upgrade leads to the same vulnerability of modifying app/code/core files -- needing you to diff the files out on upgrades.

Your proper course of action is modifying a single local.xml with your additions or overrides. If that doesn't suffice, use the proper syntax to create a module in app/code/community with your layout definitions and custom layout XML files.

Answer 5

The "right" block is probably being removed with a <remove name="right" /> at some point in the layout. If so, this will cause the "catalog.product.related" block to never be added to the layout in the first place so there is no block to insert into the "left" block.

I'm pretty sure this is the issue, but to confirm, add a Mage::log("Removed $blockName"); in Mage_Core_Model_Layout->generateXml() inside the for loop and check the log after loading the page.

If I'm right, simply copy the <block..> into your local.xml and remove the "unsetChild" and "insert" actions.

Answer 6

An alternative approach is to rename the "right" block to "left" rather than move blocks from right to left. However, this will not work if the "right" block is being removed in the first place as I suggested might be the case in my other answer.

<remove name="left" />
<reference name="right">
  <action method="setNameInLayout"><name>left</name></action>
</reference>
<reference name="root">
  <action method="setChild"><alias>left</alias><name>left</name></action>
  <action method="unsetChild"><alias>right</alias></action>
</reference>
<!-- make sure nothing referencing "right" comes after this! -->

Answer 7

If you are just looking to change the output from 2col-right, to 2col-left, it would have been much, much easier to just change

<reference name="right" ...

to

<reference name="left" ...

There is no need to unset or insert any children or re-declare anything. You are overcomplicating things and duplicating code needlessly.

If you are making your own very besoke design too, I would suggest starting copying the entire ./app/design/frontend/base directory to ./app/design/frontend/mypackage - then work from the mypackage/default directory to re-skin your site. Its cleaner and easier. Others may comment on the potential issues of upgrade-ability if you copy every file (rather than just the ones you intend to modify), but it is by far a better practice and much less prone to errors, difficulties and general maintenance.

Edit: To follow up on this in more detail - have a look https://magento.stackexchange.com/a/3794/361