You have a lookup field in a table. And when adding a new record to the table, you want that field to be set to the first value by default (rather than being empty).
Files to edit
Add the following code to hooks/tablename-dv.js (where tablename is the name of the concerned table). If the file doesn’t exist, create it. Change tablename and lookup_fieldname above to the actual table name and lookup field name.
$j(function() {
// Run this code only if this is a new record
if($j('[name=SelectedID]').val().length) return;
setTimeout(function() {
$j.ajax({
url: 'ajax_combo.php',
data: {
s: '',
p: 1,
t: 'tablename',
f: 'lookup_fieldname'
},
success: function(data) {
if(data.results.length < 2) return;
$j('#lookup_fieldname-container').select2('data', data.results[1]);
}
})
}, 1000); // this delay might be necessary to ensure all select2 is loaded first
})