Changing radiolist to dropdown - php

Question

I have stuck ;/ I have activeradiolist and works ok, but I need to create another list bud with dropdowns item's
my code with $model for activeradioList
echo Html::activeradioList($add, 'type_contact',
$items, ['item' => function ($index, $label, $name, $checked, $value) {
$return = '<div style="max-height:178px!important;" class="radio col-xs-12 col-lg-6"><input type="radio" name="' . $name . '" value="' . $value . '" tabindex="3" id="' . $name . $index . '" ' . ($checked ? 'checked' : '') . '>';
$return .= '<label style="padding-top:0!important" for="' . $name . $index . '">' . $label . '</label></div>';
if ($checked && $index === 1) {
$return .= '<script>$(document).ready(function(){$(\'#ref-form\').slideDown()});</script>';
}
return $return;
}]
); ?>
Now i try to convert this to dropdownList like ->
echo CHtml::dropDownList($add, 'type_contact',
$items, ['item' => function ($index, $label, $name, $checked, $value) {
$return = '<div style="max-height:178px!important;" class="radio col-xs-12 col-lg-6"><input type="radio" name="' . $name . '" value="' . $value . '" tabindex="3" id="' . $name . $index . '" ' . ($checked ? 'checked' : '') . '>';
$return .= '<label style="padding-top:0!important" for="' . $name . $index . '">' . $label . '</label></div>';
if ($checked && $index === 1) {
$return .= '<script>$(document).ready(function(){$(\'#ref-form\').slideDown()});</script>';
}
return $return;
}]
); ?>
and have htmlspecialchars() expects parameter 1 to be string, object given

Answer 1

1) The CHtml is class from old Yii 1.x framework. Yii2 doesn't use the C prefix for its class names.
2) You are pairing the form field with your model instance so you should use the activeDropDownList() method instead of dropDownList().
3) In your radio button options you have item callback that is used to generate the html code for radio button. The drop down list doesn't have anything like that so you should remove it from its options. You can completly omit the fourth parameter because the item callback is the only option there.
So the code for drop down list should look like this:
echo Html::activeDropDownList($add, 'type_contact', $items);