PloneBatch usage

The main steps of including the PloneBatch in your template will be to import the Batch, make a batch from your resultset, use the navigation macro and iterate over the batch elements.

Source code in this example comes from the search.pt template in Plone.

First step, set up your Batch

In the beginning of your template you would import Batch from Plone and define some variables used by it:

  <div metal:fill-slot="main"
       tal:define="results python:here.queryCatalog();
                   Batch python:modules['Products.CMFPlone'].Batch;
                   b_size python:30;
                   b_start python:0;
                   b_start request/b_start | b_start;">

results is the list to make batch from. In this case it is the results of a search (catalog query), but it can be any list.

Batch is imported from Products.CMFPlone and made available in the template as Batch.

b_size is the batch size, the number of elements to display in each batch.

b_start is the first element in the batch. It is retrieved from the request, or 0 if not found. Usually you will see b_start set to different values in the URL when you navigate around the pages in the result.

Second step, make a batch from the results

After setting up Batch and other variables, we are ready to make the batch from our result:

  <div tal:condition="results"
       tal:define="batch python:Batch(results, 
                                      b_size, 
                                      int(b_start),
                                      orphan=1);">

If the next batch would contain no more than orphan elements, it is combined with the current batch. In this case, if the next batch would contain only 1 element, it is combined with the current page.

Third step, make a navigation menu

For your convenience we have provided a macro to make the navigation menus. This macro will typically be called before and after iterating over the items in the batch:

  <div metal:use-macro="here/batch_macros/macros/navigation" />

The result will be something similar to this:

  «Previous 30    1 2 3 4 [5] 6 7 8 ...Last    Next 30»

Fourth step, iterate over the batch

Now you are ready to iterate over the batch. This is done exactly as you would iterate over the regular result set:

  <metal:block tal:repeat="result batch">
      <p tal:content="result/getURL">
      The URL from result will be written here
      </p>
  </metal:block>

You might want to call the navigation macro again after iterating over the result to get a navigation menu both above and below the result.