聊天不会自动显示新消息

Question

发送消息后，聊天不会实时出现。它需要刷新页面以获取消息。我从A发送一条消息，我必须在B端刷新以获取该消息。知道为什么吗？

脚本

<script src="https://js.pusher.com/6.0/pusher.min.js"></script>

<script>
    var receiver_id = '';
    var my_id = "{{ Auth::id() }}";
    $(document).ready(function () {
        // Enable pusher logging - don't include this in production
        Pusher.logToConsole = true;

        var pusher = new Pusher('97ac3a8652d7c9cc98dc', {
            cluster: 'ap2',
            forceTLS: true
        });

        var channel = pusher.subscribe('my-channel');
        channel.bind('my-event', function(data) {
           alert(JSON.stringify(data));
        });
    });
</script>

控制器

public function sendMessage(Request $request)
    {
        $from = Auth::id();
        $to = $request->receiver_id;
        $message = $request->message;

        $data = new Message();
        $data->from = $from;
        $data->to = $to;
        $data->message = $message;
        $data->is_read = 0; // message will be unread when sending message
        $data->save();

        // pusher
        $options = array(
            'cluster' => 'ap2'

        );

        $pusher = new Pusher(
            env('PUSHER_APP_KEY'),
            env('PUSHER_APP_SECRET'),
            env('PUSHER_APP_ID'),
            $options
        );

        $data = ['from' => $from, 'to' => $to]; // sending from and to user id when pressed enter
        $pusher->trigger('my-channel', 'my-event', $data);
    }