Send your first message

Use one-to-one text messaging to confirm that OpenIM is integrated correctly. Before starting, complete SDK initialization and sign-in in Authenticate and manage a session.

Before you start

• Prepare a test account for the sender and another for the receiver.
• Initialize the SDK for both accounts as described in Authenticate and manage a session. Register the following listener on the receiver before it signs in.
• Replace user_b in the example with the receiver's actual userID.

Step 1: Listen for incoming messages on the receiver

Register the message listener on the receiver before sign-in. When a message arrives, add it to the chat list or refresh the UI.

OpenIMClient.getInstance()
    .messageManager
    .setAdvancedMsgListener(new OnAdvanceMsgListener() {
        @Override
        public void onRecvNewMessage(Message message) {
            // Display message in the chat UI.
        }
    });

Step 2: Confirm that sending is available

After both accounts sign in, the sender can send only after its login callback succeeds and OnConnListener.onConnectSuccess() arrives. Keep the receiver connected so it can receive the new message. If a connection is not ready, wait for it to recover instead of calling login() again.

Step 3: Send a text message

Send a one-to-one text message

Create the message, then send it. Put the receiver's userID in the user destination and leave the group destination empty.

Message message = OpenIMClient.getInstance()
    .messageManager
    .createTextMessage("Hello, OpenIMSDK");

OnMsgSendCallback sendCallback = new OnMsgSendCallback() {
    @Override
    public void onProgress(long progress) {
        // Text messages usually do not need progress handling.
    }

    @Override
    public void onError(int code, String error) {
        // Tell the user that sending failed and allow a retry.
    }

    @Override
    public void onSuccess(Message sentMessage) {
        // Update the sender's chat UI with sentMessage.
    }
};

OpenIMClient.getInstance().messageManager.sendMessage(
    sendCallback,
    message,
    "user_b",
    "",
    new OfflinePushInfo()
);

OfflinePushInfo configures offline-push content. For this first test, pass an empty object and add a title, summary, or extra data later if needed.

onSuccess() means the sender has sent the message successfully. onRecvNewMessage() on the receiver means the other side received it. Both callbacks should arrive before considering this one-to-one test complete.

Send a group text message

To send a group message, leave the receiver userID empty and provide the group's groupID:

Message groupMessage = OpenIMClient.getInstance()
    .messageManager
    .createTextMessage("Hello, OpenIMSDK");

OpenIMClient.getInstance().messageManager.sendMessage(
    sendCallback,
    groupMessage,
    "",
    "group_123",
    new OfflinePushInfo()
);

Set either userID or groupID in a single call, never both.

Verify success

• The sender enters onSuccess().
• The receiver enters onRecvNewMessage() and sees the text message.
• A one-to-one message sets only the receiver's userID; a group message sets only groupID.

Next steps

• Authenticate and manage a session
• OpenIM Android SDK overview