注意：尝试获取非对象的属性... styles-customizer.php第150行

Since a server 500 issue and fix by support we have the above notice on our mobile site (no desktop site) powered by WPtouch plugin on wordpress.

In styles-customizer.php I find the following info on line 150.

// Plugins that declare styles class: XXX in header
foreach( (array) $this->plugin->child->plugins as $plugin )     {
    // Class contains method get_json_path()
    if( method_exists( $plugin, 'get_json_path' ) ) {
        $json_files[] = $plugin->get_json_path();

I'm not familiar with php at all, so if anyone can help explain it as if to a 5 year old that would be helpful.

Put you code in this condition:

if (isset($this->plugin->child->plugins)) {
     foreach .... bla bla bla
}