Polling for data updates

Polling is a communication technique used to retrieve real-time data by periodically fetching the data. This page shows you how to establish a data polling mechanism for your applications.

Real-Time Data using Polling

1. Configure the fetch query and connect it with a Table widget to display the data.

Example: To display real-time delivery status updates from a query, add the following code into the Table data property.

{{delivery_data.data}}

2. Drop a Switch widget to enable the toggling of updates at regular intervals.

3. Create a new JSObject and configure the function using the setInterval() function to implement polling:

Example: When the switch is turned on, the query is executed every 5 seconds. If the switch is turned off, use the clearInterval() function to stop the polling process:

export default {
    startAutoRefresh() {
        if (Switch1.isSwitchedOn) {
            setInterval(() => delivery_data.run(), 5000, "autorefresh");
        } else {
             clearInterval("autorefresh");
        }
    }
}

3. Set the onChange event of the Switch widget to execute the JS function.