> ## Documentation Index
> Fetch the complete documentation index at: https://cometchat-22654f5b-docs-angular-v5-docs-update.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Reactions
> Add, remove, and fetch message reactions in real-time using the CometChat iOS SDK. Includes listener events and helper methods for updating UI.
```swift theme={null}
// Add a reaction
CometChat.addReaction(messageId: 148, reaction: "\u{1F60A}") { msg in } onError: { err in }
// Remove a reaction
CometChat.removeReaction(messageId: 148, reaction: "\u{1F60A}") { msg in } onError: { err in }
// Fetch reactions for a message
let request = ReactionsRequestBuilder().setMessageId(messageId: 148).setLimit(limit: 10).build()
request.fetchNext { reactions in } onError: { error in }
// Listen for reaction events (CometChatMessageDelegate)
func onMessageReactionAdded(reactionEvent: ReactionEvent) { }
func onMessageReactionRemoved(reactionEvent: ReactionEvent) { }
```
Enhance user engagement in your chat application with message reactions. Users can express their emotions using reactions to messages. This feature allows users to add or remove reactions, and to fetch all reactions on a message.
***
## Add a Reaction
Users can add a reaction to a message by calling `addReaction` with the message ID and the reaction emoji.
```swift theme={null}
CometChat.addReaction(messageId: 148, reaction: "😴") { message in
print("Reactions: \(message.getReactions())")
} onError: { error in
print("Error: \(error?.errorDescription)")
}
```
You can react on Text, Media and Custom messages.
***
## Remove a Reaction
Removing a reaction from a message can be done using the `removeReaction` method.
Both `addReaction()` and `removeReaction()` return a [`BaseMessage`](/sdk/reference/messages#basemessage) object with the updated reactions.
```swift theme={null}
CometChat.removeReaction(messageId: 148, reaction: "😴") { message in
print("Reactions: \(message.getReactions())")
} onError: { error in
print("Error: \(error?.errorDescription)")
}
```
***
## Fetch Reactions for a Message
To get all reactions for a specific message, create a `ReactionsRequest` using `ReactionsRequestBuilder`.
| Method | Description |
| ------------------------------- | -------------------------------------- |
| `setMessageId(messageId: Int)` | Specifies the message ID (required) |
| `setReaction(reaction: String)` | Filter by specific emoji (optional) |
| `setLimit(limit: Int)` | Number of reactions to fetch (max 100) |
### Fetch Next Reactions
```swift theme={null}
let reactionsRequest = ReactionsRequestBuilder()
.setLimit(limit: 30)
.setMessageId(messageId: 148)
.build()
reactionsRequest.fetchNext { reactions in
for reaction in reactions {
print("Reaction: \(reaction.reaction)")
print("Reacted by: \(reaction.reactedBy?.name ?? "")")
}
} onError: { error in
print("Error: \(error?.errorDescription)")
}
```
### Fetch Reactions for Specific Emoji
```swift theme={null}
let reactionsRequest = ReactionsRequestBuilder()
.setLimit(limit: 30)
.setMessageId(messageId: 148)
.setReaction(reaction: "👍")
.build()
reactionsRequest.fetchNext { reactions in
// Only returns 👍 reactions
} onError: { error in
print("Error: \(error?.errorDescription)")
}
```
### Fetch Previous Reactions
```swift theme={null}
reactionsRequest.fetchPrevious { reactions in
for reaction in reactions {
print("Reaction: \(reaction.stringValue())")
}
} onError: { error in
print("Error: \(error?.errorDescription)")
}
```
***
## Real-time Reaction Events
Keep the chat interactive with real-time updates for reactions.
```swift theme={null}
let listenerID = "UNIQUE_LISTENER_ID"
CometChat.addMessageListener(listenerID, self)
extension YourViewController: CometChatMessageDelegate {
func onMessageReactionAdded(reactionEvent: ReactionEvent) {
print("Reaction Added")
print("Reaction: \(reactionEvent.reaction)")
print("Message ID: \(reactionEvent.reaction.messageId)")
print("Reacted By: \(reactionEvent.reaction.reactedBy?.name ?? "")")
}
func onMessageReactionRemoved(reactionEvent: ReactionEvent) {
print("Reaction Removed")
print("Reaction: \(reactionEvent.reaction)")
}
}
// Remove listener when done:
CometChat.removeMessageListener(listenerID)
```
***
## Get Reactions List
To retrieve the list of reactions on a particular message. Returns an array of [`ReactionCount`](/sdk/reference/auxiliary#reactioncount) objects:
```swift theme={null}
let reactions = message.reactions // Returns [ReactionCount]
```
***
## Check if Logged-in User Has Reacted
```swift theme={null}
for reactionCount in message.reactions {
print("Reaction: \(reactionCount.reaction)")
print("Reacted by me: \(reactionCount.reactedByMe)")
}
```
***
## Update Message With Reaction Info
When you receive a real-time reaction event, use this method to update the message with the latest reaction information. This keeps your local message state in sync with the server.
### Method Signature
```swift theme={null}
CometChat.updateMessageWithReactionInfo(
baseMessage: BaseMessage,
messageReaction: MessageReaction,
action: ReactionAction
) -> BaseMessage
```
### Parameters
| Parameter | Type | Description |
| --------------- | ---------------------------------------------------- | ---------------------------------------- |
| baseMessage | [`BaseMessage`](/sdk/reference/messages#basemessage) | The message to update |
| messageReaction | `MessageReaction` | Reaction info from event |
| action | `ReactionAction` | `.REACTION_ADDED` or `.REACTION_REMOVED` |
### ReactionAction Enum Values
| Value | Description |
| ------------------- | --------------------------------------- |
| `.REACTION_ADDED` | A reaction was added to the message |
| `.REACTION_REMOVED` | A reaction was removed from the message |
### Usage Example - Reaction Added
```swift theme={null}
extension YourViewController: CometChatMessageDelegate {
func onMessageReactionAdded(reactionEvent: ReactionEvent) {
// Get the message from your local list
var message: BaseMessage = getMessageFromList(reactionEvent.reaction.messageId)
// Get the reaction from the event
let messageReaction: MessageReaction = reactionEvent.reaction
// Update the message with new reaction info
let modifiedMessage = CometChat.updateMessageWithReactionInfo(
baseMessage: message,
messageReaction: messageReaction,
action: .REACTION_ADDED
)
// Update your UI with the modified message
updateMessageInList(modifiedMessage)
}
}
```
### Usage Example - Reaction Removed
```swift theme={null}
extension YourViewController: CometChatMessageDelegate {
func onMessageReactionRemoved(reactionEvent: ReactionEvent) {
// Get the message from your local list
var message: BaseMessage = getMessageFromList(reactionEvent.reaction.messageId)
// Get the reaction from the event
let messageReaction: MessageReaction = reactionEvent.reaction
// Update the message with removed reaction info
let modifiedMessage = CometChat.updateMessageWithReactionInfo(
baseMessage: message,
messageReaction: messageReaction,
action: .REACTION_REMOVED
)
// Update your UI with the modified message
updateMessageInList(modifiedMessage)
}
}
```
### Complete Real-Time Handling Example
```swift theme={null}
class ChatViewController: UIViewController, CometChatMessageDelegate {
var messages: [BaseMessage] = []
override func viewDidLoad() {
super.viewDidLoad()
CometChat.addMessageListener("reaction-listener", self)
}
func onMessageReactionAdded(reactionEvent: ReactionEvent) {
handleReactionEvent(reactionEvent, action: .REACTION_ADDED)
}
func onMessageReactionRemoved(reactionEvent: ReactionEvent) {
handleReactionEvent(reactionEvent, action: .REACTION_REMOVED)
}
private func handleReactionEvent(_ event: ReactionEvent, action: ReactionAction) {
let messageId = event.reaction.messageId
// Find the message in local list
guard let index = messages.firstIndex(where: { $0.id == messageId }) else {
return
}
// Update message with reaction info
let updatedMessage = CometChat.updateMessageWithReactionInfo(
baseMessage: messages[index],
messageReaction: event.reaction,
action: action
)
// Replace in list and refresh UI
messages[index] = updatedMessage
tableView.reloadRows(at: [IndexPath(row: index, section: 0)], with: .none)
}
deinit {
CometChat.removeMessageListener("reaction-listener")
}
}
```
**Notes:**
* This is a synchronous method - no callbacks needed
* Always use this method to keep local message state in sync
* The returned message has updated reactions array
* Works with both user and group messages
* Handle both `REACTION_ADDED` and `REACTION_REMOVED` events
***
## ReactionCount Object Properties
| Property | Type | Description |
| ------------- | -------- | ------------------------------ |
| `reaction` | `String` | The reaction emoji |
| `count` | `Int` | Number of users who reacted |
| `reactedByMe` | `Bool` | Whether logged-in user reacted |
***
## MessageReaction Object Properties
| Property | Type | Description |
| ----------- | --------------------------------------- | --------------------------- |
| `reaction` | `String` | The reaction emoji |
| `reactedBy` | [`User`](/sdk/reference/entities#user)? | User who added the reaction |
| `reactedAt` | `Double` | Unix timestamp when reacted |
| `messageId` | `Int` | ID of the message |
***
## ReactionEvent Object Properties
| Property | Type | Description |
| ----------------- | -------------- | ------------------------------- |
| `reaction` | `Reaction` | The reaction details |
| `receiverId` | `String` | ID of the receiver |
| `receiverType` | `ReceiverType` | `.user` or `.group` |
| `conversationId` | `String` | ID of the conversation |
| `parentMessageId` | `Int` | Parent message ID (for threads) |
***
## Common Error Codes
| Error Code | Description | Resolution |
| ------------------------ | -------------------------- | ------------------- |
| `ERR_MESSAGE_NOT_FOUND` | Message doesn't exist | Verify message ID |
| `ERR_INVALID_REACTION` | Invalid reaction emoji | Use valid emoji |
| `ERR_ALREADY_REACTED` | Already reacted with emoji | Remove first |
| `ERR_REACTION_NOT_FOUND` | Reaction not on message | User hasn't reacted |
***
## Next Steps
Send text, media, and custom messages to users and groups
Listen for incoming messages in real-time and fetch missed messages
Mention specific users in messages
Organize conversations with message threads