add history of changes to all entitys

common/models/ChangeHistory.php

@@ -25,4 +25,14 @@ class ChangeHistory extends \yii\db\ActiveRecord
     {
 
     }
+
+    public function afterFind()
+    {
+        parent::afterFind(); // TODO: Change the autogenerated stub
+        //milliseconds to date
+        if ($this->field_name == 'dt_start' || $this->field_name == 'dt_end' || $this->field_name == 'dt_add') {
+            $this->old_value = date('d-m-Y', $this->old_value);
+            $this->new_value = date('d-m-Y', $this->new_value);
+        }
+    }
 }