On new node create , Drupal is giving error message "The file used in the Image field may not be referenced." - drupal-7

Question

When I am gong to create a new node of a type , then upload the image field , its showing an error "The file used in the Image field may not be referenced.". I have implemented the hook_file_insert function in which it was told to use file_usage_add. I have my code below:
function mymodule_file_insert($file){
if($file->source=="field_image_und_0" || $file->source=="field_twitter_image_und_0"){
mymodule_manage_file($file);
}
}
/**
* implements file manage
*/
function mymodule_manage_file($file){
if($file->fid){
mymodule_save_file($file->fid);
}
}
/**
* implements save file
*/
function mymodule_save_file($file_id){
$file = file_load($file_id);
$file->status = FILE_STATUS_PERMANENT;
file_save($file);
file_usage_add($file, 'file', 'node', $nid);
}
Here I get here the nid when new node is creating?

Answer 1

Your are passing the $nid, and it has not value. I think this should works:
function mymodule_file_insert($file){
if($file->source=="field_image_und_0" || $file->source=="field_twitter_image_und_0"){
mymodule_manage_file($file);
}
}
/**
* implements file manage
*/
function mymodule_manage_file($file){
if($file->fid){
mymodule_save_file($file->fid);
}
}
/**
* implements save file
*/
function mymodule_save_file($file_id, $nid){
$file = file_load($file_id);
if (isset($nid)) {
file_usage_add($file, 'file', 'node', $nid);
}else {
$file->status = FILE_STATUS_PERMANENT;
file_save($file);
}
}
/**
* Implements hook_node_insert().
*/
function mymodule_node_insert($node) {
mymodule_save_file($node->field_name[LANGUAGE_NONE][0]['fid'],
$node->nid);
}