- vendorId = [(__bridge NSNumber *)IOHIDDeviceGetProperty(dev, CFSTR(kIOHIDVendorIDKey)) intValue];
- productId = [(__bridge NSNumber *)IOHIDDeviceGetProperty(dev, CFSTR(kIOHIDProductIDKey)) intValue];
+ _vendorId = [(__bridge NSNumber *)IOHIDDeviceGetProperty(dev, CFSTR(kIOHIDVendorIDKey)) intValue];
+ _productId = [(__bridge NSNumber *)IOHIDDeviceGetProperty(dev, CFSTR(kIOHIDProductIDKey)) intValue];