Customer custom attribute value not getting set

Question

I have created a custom attribute for a customer in Magento 2 and when I tried to save the value it gives me an error "Trying to get property of non-object".

How can I save the attribute value? Here is my code to save the attribute. Any help.

$customer is the factory class of customer

$customer->setCustomAttribute('custom', 'hello');
$customer->save();


$customerSetup = $this->customerSetupFactory->create(['setup' => $setup]);
        $customerEntity = $customerSetup->getEavConfig()->getEntityType('customer');
        $attributeSetId = $customerEntity->getDefaultAttributeSetId();

        $attributeSet = $this->attributeSetFactory->create();
        $attributeGroupId = $attributeSet->getDefaultGroupId($attributeSetId);

        $customerSetup->addAttribute(
                \Magento\Customer\Model\Customer::ENTITY,
                'custom',
                [
                    'type'         => 'varchar',
                    'label'        => 'custom',
                    'input'        => 'text',
                    'required'     => false,
                    'visible'      => false,
                    'user_defined' => true,
                    'sort_order' => 90,
                    'position' => 90,
                    'system' => 0,
                ]

            );
        $attribute = $customerSetup->getEavConfig()->getAttribute(\Magento\Customer\Model\Customer::ENTITY, 'custom')
            ->addData([
                'attribute_set_id' => $attributeSetId,
                'attribute_group_id' => $attributeGroupId,
                'used_in_forms' => ['adminhtml_checkout','adminhtml_customer','adminhtml_customer_address','customer_account_edit','customer_address_edit','customer_register_address'],
            ]);

        $attribute->save();

Answer 1

Try Loading customer with customer repository like below:

protected $_customerRepositoryInterface;
public function __construct(
    ....
    \Magento\Customer\Model\Customer $customerModel,
    ....
) {
    ....
    $this->customerModel = $customerModel;
}

Then load customer and set value of custom attribute like below:

$customerId = 1;
$customer = $this->customerModel->load($customerId);
$customer->setData('custom','value') // or $customer->setCustom('value');
$customer->save();

Answer 2

I have created two customer custom attributes user_name and recovery_email. Now while creating or updating customer I am using the following code. Hope this will help you as well.

User required classes

 use Magento\Framework\Exception\LocalizedException;

Declare customer factory member in your class

 /**
 * @var \Magento\Customer\Model\CustomerFactory
 */
protected $customerFactory;

Initialize it in the constructor

 public function __construct(
    ....
    \Magento\Customer\Model\CustomerFactory $customerFactory,
    .....
) {
    ....
    $this->customerFactory  = $customerFactory;
   .....
}

Use in your class methods

       try {
               // Instantiate object
                $websiteId = 1; //for now later you can update accordingly
                $customerObj = $this->customerFactory->create();
                $customerObj->setWebsiteId($websiteId);

                // Preparing data for new customer
                $customerObj->setEmail($email);
                $customerObj->setFirstname($firstName);
                $customerObj->setLastname($lastName);
                $customerObj->setPassword($password);
                $customerObj->setUserName($userName); //attribute code is user_name
                $customerObj->setRecoveryEmail($email); //attribute code is recovery_email

                // Save data
                $customerObj->save();
                $customerObj->sendNewAccountEmail();


            }catch (\Exception $exception){
                throw new LocalizedException(__($exception->getMessage()));
            }

Feel free to comment if there is an issue. Here you can use

 //$customerObj->setUserName($userName);
 $customerObj->setCustom('value');