Custom Field Handlers for Views

This is the goal: Extending the<wbr></wbr> schedulermodule <wbr>tobe able to view a countdown until a node is published orunpublished. Countdown meaning "How many time units until the nodeis published or unpublished". This would be the perfect job for theviews module. Scheduler already exposes its publish_on andunpublish_on fields for use with views.</wbr>

Defining the supported views version in filescheduler.module

<?php
function<wbr></wbr> scheduler_views_api (){
<wbr><wbr></wbr></wbr> $info [ 'api' ]=<wbr></wbr> 2 ;
<wbr> return<wbr></wbr></wbr> $info ;
}
?>

Defining the table and fields in filescheduler.views.inc:

<?php
function<wbr></wbr>scheduler_views_data(){
<wbr><wbr></wbr></wbr>$tables['scheduler']['table']['group']=<wbr></wbr>t('Scheduler');

<wbr><wbr></wbr></wbr>//how is the scheduler table linked to the nodes
<wbr><wbr></wbr></wbr>$tables['scheduler']['table']['join']['node']= array(
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'left_field'<wbr></wbr>=><wbr></wbr>'nid',
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'field'<wbr></wbr>=><wbr></wbr>'nid',
<wbr> );<br style="margin:0px; padding:0px"><br style="margin:0px; padding:0px"><wbr><wbr></wbr></wbr></wbr>//description of the fields (table columns)
<wbr><wbr></wbr></wbr>$tables['scheduler']['publish_on']= array(
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'title'<wbr></wbr>=><wbr></wbr>t('Publishon'),
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'help'<wbr></wbr>=><wbr></wbr>t('Date/timeon which the article will be automaticallypublished'),
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'field'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'views_handler_field_date',
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'clicksortable'<wbr></wbr>=><wbr></wbr>TRUE,
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>'filter'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'views_handler_filter_date',
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'label'<wbr></wbr>=><wbr></wbr>t('Publishon'),
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>'sort'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'views_handler_sort_date',
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr> );<br style="margin:0px; padding:0px"><br style="margin:0px; padding:0px"><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>$tables['scheduler']['unpublish_on']= array(
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'title'<wbr></wbr>=><wbr></wbr>t('Unpublishon'),
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'help'<wbr></wbr>=><wbr></wbr>t('Date/timeon which the article will be automaticallyunpublished'),
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'field'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'views_handler_field_date',
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'clicksortable'<wbr></wbr>=><wbr></wbr>TRUE,
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>'filter'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'views_handler_filter_date',
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'label'<wbr></wbr>=><wbr></wbr>t('Unpublishon'),
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>'sort'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'views_handler_sort_date',
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr> );<br style="margin:0px; padding:0px"><br style="margin:0px; padding:0px"><wbr> return<wbr></wbr></wbr></wbr></wbr></wbr></wbr>$tables;
}
?>

Since we just exposed existing DB fields we only needed to definehow the scheduler table is to be joined with the node table. Fordisplaying the values we could rely on a predefined handler fordate values (views_handler_field_date).That is the code that we need to build upon.

What we need now is a custom handler because there is no predefinedhandler for our purpose. At first we need to define the field.Let's start with a simple second count down:

<?php
<wbr> $tables</wbr>['scheduler']['publish_countdown']= array(
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'title'<wbr></wbr>=><wbr></wbr>t('Publishcountdown'),
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'help'<wbr></wbr>=><wbr></wbr>t('Timeuntil the article will be automaticallypublished'),
<wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr>'field'<wbr></wbr>=>array(
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'handler'<wbr></wbr>=><wbr></wbr>'scheduler_handler_field_scheduler_countdown',
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'clicksortable'<wbr></wbr>=><wbr></wbr>FALSE,
<wbr><wbr><wbr><wbr><wbr><wbr></wbr></wbr></wbr></wbr></wbr></wbr>'timestamp_field'<wbr></wbr>=><wbr></wbr>'publish_on',
<wbr><wbr><wbr> ),<br style="margin:0px; padding:0px"><wbr> );<br style="margin:0px; padding:0px"></wbr></wbr></wbr></wbr>?>