我正在尝试在我的 Yii-2 高级应用程序的后端实现 Metronic 主题。我一步一步按照 GitHub 上的说明进行操作，但是我不断收到一个空白页面，上面有以下错误。我真的被困住了。
这是错误：
An Error occurred while handling another error:
Error: Call to undefined method yii\base\ErrorException::getSeverity() in
C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\ErrorHandler.php:287
Stack trace:
#0 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\ErrorHandler.php(107):
yii\base\ErrorHandler->logException(Object(yii\base\ErrorException))
#1 [internal function]: yii\base\ErrorHandler-
>handleException(Object(yii\base\ErrorException))
#2 {main}
Previous exception:
yii\base\ErrorException: Illegal string offset 'id' in
C:\xampp\htdocs\advanced\vendor\dlds\yii2-metronic\widgets\NavBar.php:59
Stack trace:
#0 C:\xampp\htdocs\advanced\vendor\dlds\yii2-
metronic\widgets\NavBar.php(59): yii\base\ErrorHandler->handleError(2,
'Illegal string ...', 'C:\\xampp\\htdocs...', 59, Array)
#1 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Object.php(107):
dlds\metronic\widgets\NavBar->init()
#2 [internal function]: yii\base\Object->__construct(Array)
#3 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\di\Container.php(381):
ReflectionClass->newInstanceArgs(Array)
#4 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\di\Container.php(156):
yii\di\Container->build('dlds\\metronic\\w...', Array, Array)
#5 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\BaseYii.php(348):
yii\di\Container->get('dlds\\metronic\\w...', Array, Array)
#6 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Widget.php(89):
yii\BaseYii::createObject(Array)
#7 C:\xampp\htdocs\advanced\backend\views\layouts\main.php(47):
yii\base\Widget::begin(Array)
#8 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\View.php(330):
require('C:\\xampp\\htdocs...')
#9 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\View.php(250):
yii\base\View->renderPhpFile('C:\\xampp\\htdocs...', Array)
#10 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Controller.php(396):
yii\base\View->renderFile('C:\\xampp\\htdocs...', Array,
Object(dektrium\user\controllers\SecurityController))
#11 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Controller.php(382):
yii\base\Controller->renderContent('\n\n <div clas...')
#12 C:\xampp\htdocs\advanced\vendor\dektrium\yii2-
user\controllers\SecurityController.php(166): yii\base\Controller-
>render('login', Array)
#13 [internal function]: dektrium\user\controllers\SecurityController-
>actionLogin()
#14 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\InlineAction.php(57):
call_user_func_array(Array, Array)
#15 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Controller.php(156):
yii\base\InlineAction->runWithParams(Array)
#16 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Module.php(523):
yii\base\Controller->runAction('login', Array)
#17 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\web\Application.php(102):
yii\base\Module->runAction('user/security/l...', Array)
#18 C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\base\Application.php(380):
yii\web\Application->handleRequest(Object(yii\web\Request))
#19 C:\xampp\htdocs\advanced\admin\index.php(15): yii\base\Application-
>run()
#20 {main}