core-bundle/src/Resources/contao/classes/DataContainer.php
protected function getPickerInputField($value, $attributes='')
	{
		$id = is_numeric($value) ? $value : md5($value);

		switch ($this->strPickerFieldType)
		{
			case 'checkbox':
				return ' <input type="checkbox" name="picker[]" id="picker_'.$id.'" class="tl_tree_checkbox" value="'.StringUtil::specialchars(\call_user_func($this->objPickerCallback, $value)).'" onfocus="Backend.getScrollOffset()"'.Widget::optionChecked($value, $this->arrPickerValue).$attributes.'>';

			case 'radio':
				return ' <input type="radio" name="picker" id="picker_'.$id.'" class="tl_tree_radio" value="'.StringUtil::specialchars(\call_user_func($this->objPickerCallback, $value)).'" onfocus="Backend.getScrollOffset()"'.Widget::optionChecked($value, $this->arrPickerValue).$attributes.'>';
		}

		return '';
	}
protected function getPickerInputField($value, $attributes='')
	{
		$id = is_numeric($value) ? $value : md5($value);

		switch ($this->strPickerFieldType)
		{
			case 'checkbox':
				return ' <input type="checkbox" name="picker[]" id="picker_'.$id.'" class="tl_tree_checkbox" value="'.StringUtil::specialchars(\call_user_func($this->objPickerCallback, $value)).'" onfocus="Backend.getScrollOffset()"'.Widget::optionChecked($value, $this->arrPickerValue).$attributes.'>';

			case 'radio':
				return ' <input type="radio" name="picker" id="picker_'.$id.'" class="tl_tree_radio" value="'.StringUtil::specialchars(\call_user_func($this->objPickerCallback, $value)).'" onfocus="Backend.getScrollOffset()"'.Widget::optionChecked($value, $this->arrPickerValue).$attributes.'>';
		}

		return '';
	}
Return the picker input field markup

@param string $value
@param string $attributes

@return string