请教一个关于yii用户验证的问题，谢谢 [ 未指定版本 ]

首先很抱歉，对不起，我实在没有钱作悬赏，但是还是希望大神们能够帮帮我，谢谢

最近学yii2遇到一点困惑，yii2里有一个IdentityInterface接口，实现了该接口的user类可以通过$app->user获取到用户登录状态，我看basic模板的源码在验证用户登录成功后有一个gohome和goback方法重定向了一下，我不太看得懂这里的额源码，所以直接redirect了，发现重定向后无法获取$app->user登陆状态了，此时为空，请问如何在重定向后能获取到该user属性该如何实现呢？
以下附上我的实现代码截图，希望有人能帮帮我

下面是一个users model，继承了IdentityInterface接口， 里面有login验证方法

class Users extends \yii\db\ActiveRecord implements IdentityInterface
{

    public $rememberMe = false;
    /**
     * @inheritdoc
     */
    public static function tableName()
    {
        return 'users';
    }

    /**
     * @inheritdoc
     */
    public function rules()
    {
        return [
            [['username', 'email', 'password', 'create_at', 'status'], 'required'],
            [['create_at'], 'safe'],
            [['status'], 'integer'],
            [['username'], 'string', 'max' => 20],
            [['email'], 'string', 'max' => 40],
            [['password'], 'string', 'max' => 64],
            [['auto_key', 'access_token'], 'string', 'max' => 30],
            [['username', 'email'], 'unique', 'targetAttribute' => ['username', 'email'], 'message' => 'The combination of Username and Email has already been taken.']
        ];
    }

    /**
     * @inheritdoc
     */
    public function attributeLabels()
    {
        return [
            'id' => 'ID',
            'username' => 'Username',
            'email' => 'Email',
            'password' => 'Password',
            'create_at' => 'Create At',
            'status' => 'Status',
            'auto_key' => 'Auto Key',
            'access_token' => 'Access Token',
        ];
    }




    public function scenarios()
    {
        return [
            'login'=>[ 'username', 'password'],
            'register'=>['username', 'password','email']
        ];
    }

    public function login()
    {
        if( !$this->validate() )
            return false;
        $user = Users::findOne( [ 'username'=>$this->username ] );
        if( $user==null )
        {
            return false;
        }
        if( $user->password != $this->password )
        {
            return false;
        }

        return Yii::$app->user->login($user, $this->rememberMe ? 3600*24*30 : 0);
    }

    public function register()
    {
        return true;
    }





    /**
     * Finds an identity by the given ID.
     *
     * @param string|integer $id the ID to be looked for
     * @return IdentityInterface|null the identity object that matches the given ID.
     */
    public static function findIdentity($id)
    {
        return static::findOne(['id'=>$id]);
    }

    /**
     * Finds an identity by the given token.
     *
     * @param string $token the token to be looked for
     * @return IdentityInterface|null the identity object that matches the given token.
     */
    public static function findIdentityByAccessToken($token, $type = null)
    {
        return static::findOne(['access_token' => $token]);
    }

    /**
     * @return int|string current user ID
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * @return string current user auth key
     */
    public function getAuthKey()
    {
        return $this->auth_key;
    }

    /**
     * @param string $authKey
     * @return boolean if auth key is valid for current user
     */
    public function validateAuthKey($authKey)
    {
        return $this->getAuthKey() === $authKey;
    }



}

然后再action里实现的代码如下

class DefaultController extends Controller
{
    public $layout = 'basic';

    public function actionIndex()
    {
        if( !Yii::$app->user->isGuest )
        {
            return  Yii::$app->getResponse()->redirect('?r=user/main/index');
        }
        else {
            $model = new Users();

            $model->setScenario('login');
            if ($model->load(Yii::$app->request->post()) && $model->login()) {
                return $this->redirect(['/user/main/index']);
            }
            else{
                return $this->render('login', ['model' => $model]);
            }
        }
    }
}

问题是，在验证通过重定向之后无法获取$app->user的属性，请问如何操作才正确呢？谢谢