ModelAdmin Customization of Searchable fields - php

Question

I got a many to many relationship between Products and Categories using Silverstripes' ORM. All is working except when I try to add a Category for a product the choices for Category is shown by user id instead of Category name. I tried to map ID to name but did not work. Below is what I tried, what am I missing?
class Product extends DataObject {
private static $db = array(
'ProductName' => 'Varchar(32)',
);
private static $many_many = array (
'Category' => 'Category'
);
}
class Category extends DataObject {
private static $db = array(
'Category' => 'Varchar(32)',
);
public function searchableFields() {
return array (
'Category' => array (
'filter' => 'ExactMatchFilter',
'title' => 'Category',
'field' => 'TextField'->setSource(
$this::get()->map('ID','Category')
)
)
);
}
private static $belongs_many_many = array (
'Product' => 'Product'
);
}

Answer 1

When Silverstripe needs to display a shorthand for a DataObject, it will call the getTitle() method on that DataObject.
getTitle() will first check if the DataObject has a Title field and return that value if it does.
If your DataObject doesn't have Title field, it will try searching for a Name field.
If it can't find a Name field either, it will default to returning the ID of your DataObject, which is probably what is happening for you.
How to fix your specific example
There's 2 ways you can fix your specific example:
Rename your DataObjects DB fields to Name or Title
Override the getTitle() method on your 2 DataObjects
Solution #1
class Product extends DataObject {
private static $db = array(
'Name' => 'Varchar(32)',
);
private static $many_many = array (
'Category' => 'Category'
);
}
class Category extends DataObject {
private static $db = array(
'Name' => 'Varchar(32)',
);
public function searchableFields() {
return array (
'Category' => array (
'filter' => 'ExactMatchFilter',
'title' => 'Category',
'field' => 'TextField'->setSource(
$this::get()->map('ID','Category')
)
)
);
}
private static $belongs_many_many = array (
'Product' => 'Product'
);
}
Solution #2
class Product extends DataObject {
private static $db = array(
'ProductName' => 'Varchar(32)',
);
private static $many_many = array (
'Category' => 'Category' );
public function getTitle() {
return $this->ProductName;
}
}
class Category extends DataObject {
private static $db = array(
'Category' => 'Varchar(32)',
);
public function searchableFields() {
return array (
'Category' => array (
'filter' => 'ExactMatchFilter',
'title' => 'Category',
'field' => 'TextField'->setSource(
$this::get()->map('ID','Category')
)
)
); }
private static $belongs_many_many = array (
'Product' => 'Product' );
public function getTitle() {
return $this->Category;
}
}
Which solution is best?
In your specific case, I would go with solution #1, because your DB fields are functionally name/title fields.
I would use solution #2 if my DataObject's title needs to use many fields. Let's say you a have Person DataObject with a first name and a last name:
public function getTitle() {
return $this->FirstName . ' ' . $this->LastName;
}