---
title: CXCallObserverDelegate
framework: callkit
role: symbol
role_heading: Protocol
path: callkit/cxcallobserverdelegate
---

# CXCallObserverDelegate

A collection of methods the system calls when a call changes state.

## Declaration

```swift
protocol CXCallObserverDelegate : NSObjectProtocol
```

## Topics

### Responding to Changes in Call State

- [callObserver(_:callChanged:)](callkit/cxcallobserverdelegate/callobserver(_:callchanged:).md)

## Relationships

### Inherits From

- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### Call information

- [CXCall](callkit/cxcall.md)
- [CXCallObserver](callkit/cxcallobserver.md)
- [CXHandle](callkit/cxhandle.md)