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Block Users

In other words, as a logged-in user, how do I block a user from sending me messages? You can block users using the blockUsers() method. Once any user is blocked, all the communication to and from the respective user will be completely blocked. You can block multiple users in a single operation. The blockUsers() method takes a List<String> as a parameter which holds the list of UIDs to be blocked. 
List<String > uids = [];
uids.add("UID1");
uids.add("UID2");
uids.add("UID3");
CometChat.blockUser(uids, onSuccess: (Map<String, dynamic> map) {
debugPrint("Blocked User Successfully $map ");
}, onError: (CometChatException e) {
debugPrint("Blocked User Unsuccessful ${e.message} ");
});
In the onSuccess() callback, you receive a Map which contains UIDs as the keys and success or fail as the value based on if the block operation for the UID was successful or not.

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Unblock Users

In other words, as a logged-in user, how do I unblock a user I previously blocked? You can unblock the already blocked users using the unblockUsers() method. You can unblock multiple users in a single operation. The unblockUsers() method takes a List<String> as a parameter which holds the list of UIDs to be unblocked. 
List<String > uids = [];
uids.add("UID1");
uids.add("UID2");
uids.add("UID3");

CometChat.unblockUser(uids, onSuccess: (Map<String, dynamic> map) {
 debugPrint("Blocked User Successfully $map ");
 }, onError: (CometChatException e) {
 debugPrint("Blocked User Unsuccessful ${e.message} ");
 });
In the onSuccess() callback, you receive a Map which contains UIDs as the keys and success or fail as the value based on if the unblock operation for the UID was successful or not.

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Get list of blocked users

In other words, as a logged-in user, how do I get a list of all users I’ve blocked? In order to fetch the list of blocked users, you can use the BlockedUsersRequest class. To use this class i.e to create an object of the BlockedUsersRequest class, you need to use the BlockedUsersRequestBuilder class. The BlockedUsersRequestBuilder class allows you to set the parameters based on which the blocked users are to be fetched. The BlockedUsersRequestBuilder class allows you to set the below parameters:

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Set Limit

This method sets the limit i.e. the number of blocked users that should be fetched in a single iteration. 
BlockedUsersRequest blockedUsersRequest =   (BlockedUsersRequestBuilder()
  ..limit = 50
  ).build();

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Set Search Keyword

This method allows you to set the search string based on which the blocked users are to be fetched. 
BlockedUsersRequest blockedUsersRequest =  (BlockedUsersRequestBuilder()
  ..limit = 50
  ..searchKeyword = "abc"
  ).build();

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Set Direction

  • CometChatBlockedUsersDirection.directionBlockedByMe - This will ensure that the list of blocked users only contains the users blocked by the logged in user.
  • CometChatBlockedUsersDirection.directionHasBlockedMe - This will ensure that the list of blocked users only contains the users that have blocked the logged in user.
  • CometChatBlockedUsersDirection.directionBoth - This will make sure the list of users includes both the above cases. This is the default value for the direction variable if it is not set.
BlockedUsersRequest blockedUsersRequest = (BlockedUsersRequestBuilder()
  ..limit = 50
  .direction = CometChatBlockedUsersDirection.directionBlockedByMe
  ).build();
Finally, once all the parameters are set in the builder class, you need to call the build() method to get the object of the BlockedUsersRequest class. Once you have the object of the BlockedUsersRequest class, you need to call the fetchNext() method. Calling this method will return a list of User objects containing n number of blocked users where N is the limit set in the builder class. 
BlockedUsersRequest blockedUsersRequest = (BlockedUsersRequestBuilder()
    ..limit = 30
  ).build();

blockedUsersRequest.fetchNext(onSuccess: (List<User> userList){
    debugPrint("Custom Message Sent Successfully : $userList ");
  }, onError: (CometChatException e){
    debugPrint("Blocked User Request failed with exception: ${e.message}");
});