Block/Unblock User - CometChat Docs

Goal

By the end of this guide you will have a chat interface where users can block and unblock other users, with a confirmation dialog before blocking, the composer automatically hidden for blocked users, and an unblock prompt displayed in its place — all coordinated through UI events so every component stays in sync.

Prerequisites

Completed the Integration Guide guide
A running CometChatProvider setup with valid credentials
An existing one-on-one chat screen using CometChatMessageList and CometChatMessageComposer

Components Used

Component / API	Purpose
`CometChatConfirmDialog`	Compound dialog for block confirmation
`CometChatMessageList`	Displays messages in the conversation
`CometChatMessageComposer`	Text input for sending messages
`useCometChatEvents`	Subscribe to UI events
`usePublishEvent`	Publish UI events
`CometChat.blockUsers()`	SDK method to block a user
`CometChat.unblockUsers()`	SDK method to unblock a user
`ui:user/blocked`	UI event fired after blocking
`ui:user/unblocked`	UI event fired after unblocking

Step 1: Block User

Call CometChat.blockUsers() with the target UID. On success, update the user object and publish the ui:user/blocked event so other components (thread panel, details panel) can react. File: ChatView.tsx

import { CometChat } from "@cometchat/chat-sdk-javascript";
import { usePublishEvent } from "@cometchat/chat-uikit-react";

const publish = usePublishEvent();

async function handleBlock(user: CometChat.User) {
  try {
    await CometChat.blockUsers([user.getUid()]);
    user.setBlockedByMe(true);
    setIsBlocked(true);
    setShowBlockDialog(false);
    publish({ type: "ui:user/blocked", user });
  } catch (error) {
    console.error("Error blocking user:", error);
  }
}

Step 2: Unblock User

Call CometChat.unblockUsers() to reverse the block. Publish ui:user/unblocked so all listening components restore their normal state. File: ChatView.tsx

async function handleUnblock(user: CometChat.User) {
  try {
    await CometChat.unblockUsers([user.getUid()]);
    user.setBlockedByMe(false);
    setIsBlocked(false);
    publish({ type: "ui:user/unblocked", user });
  } catch (error) {
    console.error("Error unblocking user:", error);
  }
}

Step 3: Confirmation Dialog

Show a CometChatConfirmDialog before blocking. Render it conditionally based on a showBlockDialog state flag. File: ChatView.tsx

import { useState } from "react";
import { CometChatConfirmDialog } from "@cometchat/chat-uikit-react";

const [showBlockDialog, setShowBlockDialog] = useState(false);

// In your JSX:
{showBlockDialog && (
  <CometChatConfirmDialog.Root isOpen={true} onClose={() => setShowBlockDialog(false)}>
    <CometChatConfirmDialog.Icon />
    <CometChatConfirmDialog.Content
      title="Block Contact"
      messageText="Are you sure you want to block this user? They won't be able to send you messages."
    />
    <CometChatConfirmDialog.Actions
      confirmButtonText="Block"
      onConfirm={() => handleBlock(user)}
      onCancel={() => setShowBlockDialog(false)}
    />
  </CometChatConfirmDialog.Root>
)}

Step 4: Listen for Block/Unblock Events

Use useCometChatEvents to subscribe to block/unblock events. This keeps the composer visibility in sync even when the block action originates from a different component (e.g., a details panel).

The ui:user/blocked and ui:user/unblocked events are part of the UI Kit’s Event System. See that page for the full list of user and group action events and the usePublishEvent / useCometChatEvents hooks.

File: ChatView.tsx

import { useCometChatEvents } from "@cometchat/chat-uikit-react";
import type { CometChatEvent } from "@cometchat/chat-uikit-react";

useCometChatEvents(
  (event: CometChatEvent) => {
    if (!user) return;

    if (event.type === "ui:user/blocked" && event.user.getUid() === user.getUid()) {
      setIsBlocked(true);
    }
    if (event.type === "ui:user/unblocked" && event.user.getUid() === user.getUid()) {
      setIsBlocked(false);
    }
  },
  [user?.getUid()]
);

Step 5: Blocked Composer State

Conditionally render the composer or a blocked prompt based on the isBlocked state. The blocked prompt includes an inline unblock action. File: ChatView.tsx

import { CometChatMessageComposer } from "@cometchat/chat-uikit-react";

// In your JSX:
{!isBlocked ? (
  <CometChatMessageComposer user={user} />
) : (
  <div style={{ padding: "16px", textAlign: "center", background: "#f5f5f5" }}>
    <p>Cannot send a message to a blocked user.</p>
    <span
      onClick={() => handleUnblock(user)}
      role="button"
      tabIndex={0}
      style={{ color: "#3399ff", cursor: "pointer" }}
    >
      Click to unblock.
    </span>
  </div>
)}

Complete Example

File: ChatView.tsx

import { useState, useEffect } from "react";
import { CometChat } from "@cometchat/chat-sdk-javascript";
import {
  CometChatProvider,
  CometChatMessageList,
  CometChatMessageComposer,
  CometChatMessageHeader,
  CometChatConfirmDialog,
  usePublishEvent,
  useCometChatEvents,
} from "@cometchat/chat-uikit-react";
import type { CometChatEvent } from "@cometchat/chat-uikit-react";

function ChatView({ targetUid }: { targetUid: string }) {
  const [user, setUser] = useState<CometChat.User | null>(null);
  const [isBlocked, setIsBlocked] = useState(false);
  const [showBlockDialog, setShowBlockDialog] = useState(false);
  const publish = usePublishEvent();

  useEffect(() => {
    async function fetchUser() {
      try {
        const fetchedUser = await CometChat.getUser(targetUid);
        setUser(fetchedUser);
        setIsBlocked(fetchedUser.getBlockedByMe());
      } catch (error) {
        console.error("Error fetching user:", error);
      }
    }
    fetchUser();
  }, [targetUid]);

  useCometChatEvents(
    (event: CometChatEvent) => {
      if (!user) return;
      if (event.type === "ui:user/blocked" && event.user.getUid() === user.getUid()) {
        setIsBlocked(true);
      }
      if (event.type === "ui:user/unblocked" && event.user.getUid() === user.getUid()) {
        setIsBlocked(false);
      }
    },
    [user?.getUid()]
  );

  async function handleBlock() {
    if (!user) return;
    try {
      await CometChat.blockUsers([user.getUid()]);
      user.setBlockedByMe(true);
      setIsBlocked(true);
      setShowBlockDialog(false);
      publish({ type: "ui:user/blocked", user });
    } catch (error) {
      console.error("Error blocking user:", error);
    }
  }

  async function handleUnblock() {
    if (!user) return;
    try {
      await CometChat.unblockUsers([user.getUid()]);
      user.setBlockedByMe(false);
      setIsBlocked(false);
      publish({ type: "ui:user/unblocked", user });
    } catch (error) {
      console.error("Error unblocking user:", error);
    }
  }

  if (!user) return <div>Loading...</div>;

  return (
    <div style={{ display: "flex", flexDirection: "column", height: "100vh" }}>
      {/* Confirmation dialog */}
      {showBlockDialog && (
        <CometChatConfirmDialog.Root isOpen={true} onClose={() => setShowBlockDialog(false)}>
          <CometChatConfirmDialog.Icon />
          <CometChatConfirmDialog.Content
            title="Block Contact"
            messageText="Are you sure you want to block this user? They won't be able to send you messages."
          />
          <CometChatConfirmDialog.Actions
            confirmButtonText="Block"
            onConfirm={handleBlock}
            onCancel={() => setShowBlockDialog(false)}
          />
        </CometChatConfirmDialog.Root>
      )}

      {/* Header with block/unblock action */}
      <CometChatMessageHeader
        user={user}
        auxiliaryButtonView={
          <button
            onClick={isBlocked ? handleUnblock : () => setShowBlockDialog(true)}
            style={{ background: "none", border: "none", cursor: "pointer", fontSize: "14px", color: isBlocked ? "#3399ff" : "#f44336" }}
          >
            {isBlocked ? "Unblock" : "Block"}
          </button>
        }
      />

      {/* Message list */}
      <div style={{ flex: 1, overflow: "hidden" }}>
        <CometChatMessageList user={user} />
      </div>

      {/* Composer or blocked prompt */}
      {!isBlocked ? (
        <CometChatMessageComposer user={user} />
      ) : (
        <div style={{ padding: "16px", textAlign: "center", background: "#f5f5f5" }}>
          <p>Cannot send a message to a blocked user.</p>
          <span
            onClick={handleUnblock}
            role="button"
            tabIndex={0}
            style={{ color: "#3399ff", cursor: "pointer" }}
          >
            Click to unblock.
          </span>
        </div>
      )}
    </div>
  );
}

function App() {
  return (
    <CometChatProvider>
      <ChatView targetUid="user-to-chat-with" />
    </CometChatProvider>
  );
}

export default App;

Next Steps

Event System — full reference for the ui:user/* events and pub/sub hooks
Message Composer — learn about composer customization
Conversations — build a full conversations list
CometChatProvider — configure the root provider

​Goal

​Prerequisites

​Components Used

​Step 1: Block User

​Step 2: Unblock User

​Step 3: Confirmation Dialog

​Step 4: Listen for Block/Unblock Events

​Step 5: Blocked Composer State

​Complete Example

​Next Steps

Goal

Prerequisites

Components Used

Step 1: Block User

Step 2: Unblock User

Step 3: Confirmation Dialog

Step 4: Listen for Block/Unblock Events

Step 5: Blocked Composer State

Complete Example

Next Steps