Fixes #1835: `CheckboxColumn` now renders checkboxes whose values are the…

framework/CHANGELOG.md

@@ -67,6 +67,7 @@ Yii Framework 2 Change Log
 - Chg #1643: Added default value for `Captcha::options` (qiangxue)
 - Chg #1647: Changed the default CSS class of error block to be `error-block` (qiangxue)
 - Chg #1796: Removed `yii\base\Controller::getActionParams()` (samdark)
+- Chg #1835: `CheckboxColumn` now renders checkboxes whose values are the corresponding data key values (qiangxue)
 - Chg: Renamed `yii\jui\Widget::clientEventsMap` to `clientEventMap` (qiangxue)
 - Chg: Renamed `ActiveRecord::getPopulatedRelations()` to `getRelatedRecords()` (qiangxue)
 - Chg: Renamed `attributeName` and `className` to `targetAttribute` and `targetClass` for `UniqueValidator` and `ExistValidator` (qiangxue)

framework/yii/grid/CheckboxColumn.php

@@ -75,6 +75,9 @@ class CheckboxColumn extends Column
 			$options = call_user_func($this->checkboxOptions, $model, $key, $index, $this);
 		} else {
 			$options = $this->checkboxOptions;
+			if (!isset($options['value'])) {
+				$options['value'] = is_array($key) ? json_encode($key) : $key;
+			}
 		}
 		return Html::checkbox($this->name, !empty($options['checked']), $options);
 	}