silverstripe-framework/src/Forms/FormTransformation.php
2017-08-22 15:47:24 +12:00

82 lines
2.9 KiB
PHP

<?php
namespace SilverStripe\Forms;
use BadMethodCallException;
use SilverStripe\Core\ClassInfo;
use SilverStripe\Core\Config\Configurable;
use SilverStripe\Core\Extensible;
use SilverStripe\Core\Injector\Injectable;
/**
* This class represents "transformations" of a form - such as making it printable or making it readonly.
* The idea is that sometimes you will want to make your own such transformations, and you shouldn't have
* to edit the underlying code to support this.
*
* The first step in creating a transformation is subclassing FormTransformation. After that, you have two
* ways of defining specific functionality:
* - Define performMyTransformation() methods on each applicable FormField() object.
* - Define transformFieldType($field) methods on your subclass of FormTransformation.
*
* To actually perform the transformation, call $form->transform(new MyTransformation());
*/
class FormTransformation
{
use Configurable;
use Injectable;
use Extensible;
public function __construct()
{
}
public function transform(FormField $field)
{
// Look for a performXXTransformation() method on the field itself.
// performReadonlyTransformation() is a pretty commonly applied method.
// Otherwise, look for a transformXXXField() method on this object.
// This is more commonly done in custom transformations
// We iterate through each array simultaneously, looking at [0] of both, then [1] of both.
// This provides a more natural failover scheme.
$transNames = array_reverse(array_map(
function ($name) {
return ClassInfo::shortName($name);
},
array_values(ClassInfo::ancestry($this))
));
$fieldClasses = array_reverse(array_map(
function ($name) {
return ClassInfo::shortName($name);
},
array_values(ClassInfo::ancestry($field))
));
$len = max(sizeof($transNames), sizeof($fieldClasses));
for ($i=0; $i<$len; $i++) {
// This is lets fieldClasses be longer than transNames
if (!empty($transNames[$i])) {
$funcName = 'perform' . $transNames[$i];
if ($field->hasMethod($funcName)) {
//echo "<li>$field->class used $funcName";
return $field->$funcName($this);
}
}
// And this one does the reverse.
if (!empty($fieldClasses[$i])) {
$funcName = 'transform' . $fieldClasses[$i];
if ($this->hasMethod($funcName)) {
//echo "<li>$field->class used $funcName";
return $this->$funcName($field);
}
}
}
$class = static::class;
$fieldClass = get_class($field);
throw new BadMethodCallException("FormTransformation:: Can't perform '{$class}' on '{$fieldClass}'");
}
}