---
title: HandleChangeCustomPropertyDataValueWithQualifier
framework: VideoDriverKit
role: symbol
role_heading: Instance Method
platforms: [driverkit 27.0+]
path: videodriverkit/iouservideocustomproperty/handlechangecustompropertydatavaluewithqualifier
---

# HandleChangeCustomPropertyDataValueWithQualifier

The system calls this virtual method when the custom property’s data value changes.

## Declaration

```occ
virtual kern_return_t HandleChangeCustomPropertyDataValueWithQualifier(OSObject *in_qualifier_data, OSObject *in_data);
```

## Parameters

- `in_qualifier_data`: The qualifier data OSObject associated with setting the property data value. Can be a nullptr, OSString, or OSDictionary.
- `in_data`: The data OSObject that is getting set for the custom property. Can be a OSString or OSDictionary.

## Return Value

Return Value kIOReturnSuccess on success. Upon success the custom property’s data value should be updated.

## Discussion

Discussion The default implementation always returns kIOReturnSuccess and updates the custom property data value without checking qualifier contents. Subclass and override this method to handle changes to this custom property value and return kIOReturnSuccess upon success.