Table of Contents

How to add screen sharing to your JavaScript app with Sendbird Calls

How to add screen sharing to your JavaScript app with Sendbird Calls

Alex Orr
Tutorial Type: Advanced Reading Time: 15 minutes Building Time: 2 hours

Note: This guide assumes that you have already completed the Part 1 of this guide, and the subsequent guide will build onto Part 1.


implement calls with video functionality. In this Part 2 we will be showing you how to implement a simple screen sharing functionality.

Step 1. Modifying the UI

Add start / stop screen share buttons

In your index.html file add a screen share and stop sharing button in the same div as your make call button from part 1.

If you run this in a Browser,  you should see something like this:

Figure 1.1 – Video area with visible screen share buttons

Now let’s apply the extra style style=”display:none” to our share screen and stop sharing buttons. We will only show these when connected to a call.

If you refresh your Browser, you should see something like this:

Step 2. Modifying the implementation

Let’s update the call.onEstablished method in the index.js file to display the screen share buttonswhen a call is connected.

Let’s also update the call.onEnded method in the index.js file to hide the screen share button when a call is disconnected.

Share your screen

Once you have an active call you can start sharing your screen. To do this, let’s implement a new function in index.js

Check for a valid current call.
Optionally, we enlarge our video element. We increase its width from 300px to 800px.
await currentCall.startScreenShare() does all the internal job for us. This is a Sendbird function.
Once we call the screen sharing function from Sendbird, we set a listener for when the remote user stops it. The logic inside this function is to reduce the size of our video element (back to 300px) and hide the Stop share screen button.

Figure 3 – Browsers internally will ask for which monitor you want to share.

Let’s apply the logic to stop screen sharing:


Now we have fully completed this tutorial. In Part 1 we implemented the functionality for making calls, and now in part 2 we have added the functionality for sharing your screen.
Please feel free to check out the below resources for the full source code, and related documentation!

Resources & documentation

Check the full source, clone and download.

Also check our official documentation and sample code.