> ## Documentation Index > Fetch the complete documentation index at: https://www.cometchat.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Receive A Message > Receive CometChat messages in Flutter apps with real-time MessageListener callbacks and missed message retrieval. Receiving messages with CometChat has two parts: 1. Adding a listener to receive [Real-time Messages](/sdk/flutter/receive-messages#real-time-messages) when your app is running 2. Calling a method to retrieve [Missed Messages](/sdk/flutter/receive-messages#missed-messages) when your app was not running ## Real-time Messages *In other words, as a recipient, how do I receive messages when my app is running?* For every activity or fragment you wish to receive messages in, you need to register the `MessageListener` using the `addMessageListener()` method. We suggest adding the listener in the `init` method of the Stateful class or at the initialization of class where you wish to receive these events in. ```dart theme={null} class Class_Name with MessageListener { //CometChat.addMessageListener("listenerId", this); @override void onTextMessageReceived(TextMessage textMessage) { debugPrint("Text message received successfully: $textMessage"); } @override void onMediaMessageReceived(MediaMessage mediaMessage) { debugPrint("Media message received successfully: $mediaMessage"); } @override void onCustomMessageReceived(CustomMessage customMessage) { debugPrint("Custom message received successfully: $customMessage"); } @override onInteractiveMessageReceived(InteractiveMessage message) { } @override void onCardMessageReceived(CardMessage cardMessage) { debugPrint("Card message received successfully: $cardMessage"); } } ``` | Parameter | Description | | ---------- | ---------------------------------------------------------------------------------------------- | | listenerID | An ID that uniquely identifies that listener. We recommend using the activity or fragment name | We recommend you remove the listener once the activity or fragment is not in use. Typically, this can be added in the `dispose()` method. ```dart theme={null} private String listenerID = "UNIQUE_LISTENER_ID"; CometChat.removeMessageListener(listenerID); ``` As a sender, you will not receive your own message in a real-time message event. However, if a user is logged-in using multiple devices, they will receive an event for their own message in other devices. ## Missed Messages *In other words, as a recipient, how do I receive messages that I missed when my app was not running?* For most use cases, you will need to add functionality to load missed messages. If you're building an on-demand or live streaming app, you may choose to skip this and fetch the message history (say, last 100 messages) instead. Using the same `MessagesRequest` class and the filters provided by the `MessagesRequestBuilder` class, you can fetch the message that we sent to the logged-in user but were not delivered to them as they were offline. For this, you will require the ID of the last message received. You can either maintain it at your end or use the `getLastDeliveredMessageId()` method provided by the CometChat class. This ID needs to be passed to the `setMessageId()` method of the builder class. Now using the `fetchNext()` method, you can fetch all the messages that were sent to the user when they were offline. Calling the `fetchNext()` method on the same object repeatedly allows you to fetch all the offline messages for the logged in user in a paginated manner ### For a Particular One-on-one Conversation ```dart theme={null} int limit = 30; int lastMessageId = -1; String UID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..uid = UID ..limit = limit ..messageId = lastMessageId ).build(); messageRequest.fetchNext(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` ### For a Particular Group Conversation ```dart theme={null} int limit = 30; int lastMessageId = -1; String GUID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..guid = GUID ..limit = limit ..messageId = lastMessageId ).build(); messageRequest.fetchNext(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` ## Unread Messages *In other words, as a logged-in user, how do I fetch the messages I've not read?* Using the `MessagesRequest` class described above, you can fetch the unread messages for the logged-in user. In order to achieve this, you need to set the `unread` variable in the builder to `true` so that only the unread messages are fetched. ### For a Particular One-on-one Conversation ```dart theme={null} int limit = 30; int lastMessageId = -1; String GUID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..guid = GUID ..limit = limit ..messageId = lastMessageId ..unread = true ).build(); messageRequest.fetchPrevious(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` ### For a Particular Group Conversation ```dart theme={null} int limit = 30; int lastMessageId = -1; String GUID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..guid = GUID ..limit = limit ..messageId = lastMessageId ..unread = true ).build(); messageRequest.fetchPrevious(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` Base Message The list of messages received is in the form of objects of `BaseMessage` class. A `BaseMessage` can either be an object of the `TextMessage`, `MediaMessage`, `CustomMessage`, `CardMessage`, `Action` or `Call` class. You can use the `is` operator to check the type of object. ## Message History *In other words, as a logged-in user, how do I fetch the message history for a user or a group conversation?* ### For a Particular One-on-one Conversation Using the `MessagesRequest` class and the filters for the `MessagesRequestBuilder` class as shown in the below code snippet, you can fetch the entire conversation between the logged in user and any particular user. For this use case, it is mandatory to set the UID parameter of the builder. This UID is the unique id of the user for which the conversation needs to be fetched. ```dart theme={null} int limit = 30; int lastMessageId = -1; String UID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..uid = UID ..limit = limit ).build(); messageRequest.fetchPrevious(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` Calling the `fetchPrevious()` method on the same object repeatedly allows you to fetch all the previous messages in a paginated way. ### For a Particular Group Conversation Using the `MessagesRequest` class and the filters for the `MessagesRequestBuilder` class as shown in the below code snippet, you can fetch the entire conversation for any group provided you have joined the group. For this use case, it is mandatory to set the GUID parameter of the builder. This GUID is the unique identifier of the Group for which the messages are to be fetched. ```dart theme={null} int limit = 30; String GUID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..guid = GUID ..limit = limit ).build(); messageRequest.fetchPrevious(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` Calling the `fetchPrevious()` method on the same object repeatedly allows you to fetch the entire conversation between the logged in user and the specified user. This can be implemented with upward scrolling to display the entire conversation. ## Search Messages In other words, as a logged-in user, how do I search a message? In order to do this, you can use the `searchKeyword` method. This method accepts string as input. When set, the SDK will fetch messages which match the `searchKeyword`. By default, the searchKey is searched only in message text. However, if you enable `Conversation & Advanced Search`, the searchKey will be searched in message text, file name, mentions & mime type of the file. The `Conversation & Advanced Search` is only available in `Advanced` & `Custom` [plans](https://www.cometchat.com/pricing). If you're already on one of these plans, please enable the `Conversation & Advanced Search` from [CometChat Dashboard](https://app.cometchat.com) (Open your app, navigate to Chats -> Settings -> General Configuration) | Feature | Basic Search | Advance Search | | ---------------- | ------------ | -------------- | | Text search | ✅ | ✅ | | File name search | ❌ | ✅ | | Mentions search | ❌ | ✅ | | Mime type search | ❌ | ✅ | ### For a Particular One-on-one Conversation ```dart theme={null} int limit = 30; int searchKeyword = "search keyboard"; String UID = "cometchat-uid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..uid = UID ..limit = limit .searchKeyword=searchKeyword ).build(); messageRequest.fetchPrevious(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` ### For a Particular Group Conversation ```dart theme={null} int limit = 30; int searchKeyword = "search keyboard"; String GUID = "cometchat-guid-1"; MessagesRequest messageRequest = (MessagesRequestBuilder() ..guid = GUID ..limit = limit .searchKeyword=searchKeyword ).build(); messageRequest.fetchPrevious(onSuccess: (List list) { for (BaseMessage message in list) { if(message is TextMessage){ debugPrint("Text message received successfully: "+(message as TextMessage).toString()); }else if(message is MediaMessage){ debugPrint("Media message received successfully: "+(message as MediaMessage).toString()); } } }, onError: (CometChatException e) { debugPrint("Message fetching failed with exception: ${e.message}"); }); ``` ## Unread Messages Count *In other words, as a logged-in user, how do I find out the number of unread messages that I have?* ### For a Particular One-on-one Conversation *In other words, how do I find out the number of unread messages I have from a particular user?* In order to get the unread message count for a particular user (with respect to the logged-in user), you can use the `getUnreadMessageCountForUser()`. This method has the two variants: ```dart theme={null} CometChat.getUnreadMessageCountForUser(String UID, Callbacks); ``` If you wish to ignore the messages from blocked users you can use the below syntax setting the boolean parameter to `true`: ```dart theme={null} CometChat.getUnreadMessageCountForUser(String UID, boolean hideMessagesFromBlockedUsers, Callbacks); ``` ```dart theme={null} private String UID = "cometchat-uid-1" CometChat.getUnreadMessageCountForUser(UID, new CometChat.CallbackListener>() { @Override public void onSuccess(HashMap stringIntegerHashMap) { // handle success } @Override public void onError(CometChatException e) { // handle error } }); ``` In the `onSuccess()` callback, you will receive a `Map` which will contain the `UID` of the user as the key and the unread message count as the value. ### For a Particular Group Conversation *In other words, how do I find out the number of unread messages I have in a single group?* In order to get the unread message count for a particular group, you can use the `getUnreadMessageCountForGroup()`. This method has two variants: ```dart theme={null} Map? ab = await CometChat.getUnreadMessageCountForGroup(guid: guid); ``` If you wish to ignore the messages from blocked users you can use the following syntax setting the boolean parameter to `true`: ```dart theme={null} Map? ab = await CometChat.getUnreadMessageCountForGroup(guid: guid,hideMessagesFromBlockedUsers: hideBlockedUser); ``` ```dart theme={null} private String GUID = "cometchat-guid-1" CometChat.getUnreadMessageCountForGroup(guid: GUID,hideMessagesFromBlockedUsers: hideBlockedUser, onSuccess: (Map map) { }, onError: (CometChatException e) { }); ``` In the `onSuccess()` callback, you will receive a `Map` which will contain the `GUID` of the group as the key and the unread message count as the value. ### For All One-on-one & Group Conversations *In other words, how do I find out the number of unread messages for every one-on-one and group conversation?* In order to get all the unread message counts, you can use the `getUnreadMessageCount()` method. This method has two variants: ```dart theme={null} await CometChat.getUnreadMessageCount(); ``` If you wish to ignore the messages from blocked users you can use the following syntax setting the boolean parameter to `true`: ```dart theme={null} await CometChat.getUnreadMessageCount(hideMessagesFromBlockedUsers: true); ``` ```dart theme={null} CometChat.getUnreadMessageCount(hideMessagesFromBlockedUsers: hideBlockedUser, onSuccess: (Map> map) { },onError: (CometChatException e) { }); ``` In the `onSuccess()` callback, you will receive a `Map` having two keys: 1. `user` - The value for this key holds another `Map` that holds the `UIDs` of users and their corresponding unread message counts. 2. `group` - The value for this key holds another `Map` that holds the `GUIDs` of groups and their corresponding unread message counts. ### For Unread Count for all One-on-one Conversations *In other words, how do I find out the number of unread messages I have for every user?* In order to fetch the unread message counts for just the users, you can use the `getUnreadMessageCountForAllUsers()` method. This method, just like others, has two variants: ```dart theme={null} await CometChat.getUnreadMessageCountForAllUsers(); ``` If you wish to ignore the messages from blocked users you can use the following syntax setting the boolean parameter to `true`: ```dart theme={null} await CometChat.getUnreadMessageCountForAllUsers(hideMessagesFromBlockedUsers: true); ``` ```dart theme={null} CometChat.getUnreadMessageCountForAllUsers(hideMessagesFromBlockedUsers: hideMessagesFromBlockedUsers, onSuccess: (Map map) { }, onError: (CometChatException e) { }); ``` In the `onSuccess()` callback, you will receive a `Map` that will contain the `UIDs` of users as the key and the unread message counts as the values. ### Fetch Unread Count for all Group Conversations *In other words, how do I find out the number of unread messages for every group?* In order to fetch the unread message counts for all groups, you can use the `getUnreadMessageCountForAllGroups()` method. This method has two variants: ```dart theme={null} await CometChat.getUnreadMessageCountForAllGroups(); ``` If you wish to ignore the messages from blocked users you can use the below syntax setting the boolean parameter to `true`: ```dart theme={null} await CometChat.getUnreadMessageCountForAllGroups(hideMessagesFromBlockedUsers: true); ``` ```dart theme={null} CometChat.getUnreadMessageCountForAllGroups(hideMessagesFromBlockedUsers: hideMessagesFromBlockedUsers, onSuccess: (Map map) { }, onError: (CometChatException e) { }); ``` In the `onSuccess()` callback, you will receive a `Map` which will contain the `GUIDs` of the groups as the key and the unread message counts as the values.