Trying to get property on a non object Yii 1.1.15 - php

Question

I try to change Css file for CGridView widget, in my config/main.php:
'components' => array(
'widgetFactory' => array(
'widgets' => array(
'CGridView' => array(
'cssFile' => Yii::app()->request->baseUrl . '/css/gridview.css',
),
),
),
...
And I get warning:
Trying to get property on a non object /path_to_project/protected/config/main.php on line 79
How I can suppress this warning, and why I getting it, in when I using it in view files it all works.
P.S. Yes I can set display_errors ini set to false and message will dissapearm but I want get clearly with it. Thanks!

Answer 1

The reason for the warning is that the CHttpRequest object Yii::app()->request has not been instantiated yet.
From the API page for CApplication:
CApplication will undergo the following lifecycles when processing a
user request:
load application configuration;
set up error handling;
load static application components;
onBeginRequest: preprocess the user request;
processRequest: process the user request;
onEndRequest: postprocess the user request;
Starting from lifecycle 3, if a PHP error or an uncaught exception occurs, the application will switch to its error handling logic and jump to step 6 afterwards.
Your error is happening at the first step. As such, Yii's error handling has not been setup yet. The only option is to suppress this warning using the # operator:
'cssFile' => #Yii::app()->request->baseUrl . '/css/gridview.css',
HOWEVER
This is a terrible idea, since you are essentially hiding the error instead of fixing it.
If your views are being displayed correctly (no css errors), you can omit the Yii::app()->request->baseUrl and just use:
'cssFile' => '/css/gridview.css'
If you are experiencing errors, you can create a class in your components folder that extends CWidgetFactory and set any variables that depend on other components here e.g
class MyWidgetFactory extends CWidgetFactory {
public function init() {
parent::init();
$this->widgets['CGridView']['cssFile'] = Yii::app()->request->baseUrl.'css/gridview.css';
}
}
You will need to adjust your components to use this file:
'components' => array(
'widgetFactory' => array(
'class' => 'MyWidgetFactory'
...