Layout update: unable to add a child block in layout XML by reference

Question

I'm having a problem where I can't seem to add a child block in a layout XML file. What am I doing wrong in mylayout.xml that I can't load abc? I have the following files.

onestepcheckout.xml

<onestepcheckout_index_index>
 ...
 <reference name="content">
 <block type="onestepcheckout/checkout" name="onestepcheckout.checkout" template="onestepcheckout/checkout.phtml">
 ...
 <!-- this child block can be loaded -->
 <block type="block/class" template="path/to/template/template.phtml" name="qwe" as="qwe" />
 ...
 </block>
 </reference>
 ...
</onestepcheckout_index_index>

mylayout.xml

<onestepcheckout_index_index>
 <reference name="onestepcheckout.checkout">
 <!-- this child block can not be loaded -->
 <block type="block/class" template="path/to/template/template.phtml" name="abc" as="abc" />
 </reference>
</onestepcheckout_index_index>

checkout.phtml

...
<?php echo $this->getChildHtml('abc') // doesn't work ?>
<?php echo $this->getChildHtml('qwer') // works ?>
...

Answer 1

If its a module loading issue, I think you should add a tag in your module declaration file. like below

<depends> <companyname_modulename/> </depends>

This will insure that your module will be loaded after companyname_modulename

Answer 2

I found out why. My extension loads first, and the extension that loads onestepcheckout_index_index is loaded after mine. Therefore, my layout update was referring to a handle that doesn't exist yet..

Answer 3

Just to clarify this. Several steps were necessary. First, declare the block as a child block.

<action method="setChild"><alias>my_name</alias><child>my.name</child></action>

Then add the dependency to your module declaration file. In my case it was Idev_OneStepCheckout

<depends>
 <Idev_OneStepCheckout />
</depends>

Finally, in the template it will only work if you use the alias.

echo $this->getChildHtml('my_name')

Answer 4

Not sure why that doesn't work either. Have you tried explicitly declaring the block as a child?

<onestepcheckout_index_index>
 <reference name="onestepcheckout.checkout">
 <!-- this child block can not be loaded -->
 <block type="block/class" template="path/to/template/template.phtml" name="abc" as="abc" />
 <action method="setChild"><child>abc</child><alias>abc</alias></action>
 </reference>
</onestepcheckout_index_index>

• laketuna: I tried it, but it still doesn't work. The strange thing is that I have other updates in my layout.xml that uses the same method, and they all work.
• laketuna: I found out why. My extension loads first, and the extension that loads onestepcheckout_index_index is loaded after mine. Therefore, my layout update was referring to a handle that doesn't exist yet..
• pzirkind: @laketuna that's very interesting, i had a similar problem recently and just used an observer, but this question sparked my curiosity again, thanks

Answer 5

If you want to add new block, you should reference structural blocks, not content blocks. Try out something like this instead:

<onestepcheckout_index_index>
 <reference name="content">
 <block type="block/class" template="path/to/template/template.phtml" name="abc" as="abc" />
 </reference>
</onestepcheckout_index_index>

• laketuna: Referring to content loads my block, but I can't control where the block gets placed if I refer to `content.
• Pronto: It gets placed by <?php echo $this->getChildHtml('abc') ?>
• laketuna: I need to place this block in a specific location. As far as I know, referencing content places the block automatically and echo $this->getChildHtml('abc') has no effect. Correct me if I'm wrong.