In this guide we are going to walk through a basic example module for the HTML Overlay application, displaying a configurable image on your screen as a channel points reward.
Create a new .js file in the Content directory. We are going to name this module image-reward.js;
Open image-reward.js in your preferred code editor. (I will be using Visual Studio Code)
Add the following code to the top of your module to read in configuration params:
// Get config from import params
const url = new URL(import.meta.url);
const config = {
// this must match the title of the Channel Points reward we want to trigger for
rewardTitle: url.searchParams.get('rewardTitle'),
// this is the URL of the image we want to display
imageUrl: url.searchParams.get('imageUrl'),
// this is the number of seconds to display the image (defaults to 5)
seconds: Number(url.searchParams.get('seconds')) || 5
}
window.streamerbot.subscribeTo({
Twitch: [ "RewardRedemption" ]
});
window.streamerbot.onMessage(message => {
if (
message.event.source === "Twitch" &&
message.event.type === "RewardRedemption" &&
message.data.title === config.rewardTitle
)
// This function is called anytime a Channel Point Reward is redeemed with a name matching our rewardTitle configuration
// We will be creating this function in the next steps
showImage();
});
showImageshowImage, we will write the code to perform the action:function showImage() {
// Create our image element
const imgElement = document.createElement("img");
// Modify the image element src to point at the configured image URL
imgElement.src = config.imageUrl;
// Append the image element to the HTML document
document.body.appendChild(imgElement);
// Set a timeout to remove the image after the configured amount of time
setTimeout(() => {
imgElement.remove();
}, config.seconds * 1000)
}
At this point, show-image.js should look something like this:
// Get config from import params
const url = new URL(import.meta.url);
const config = {
rewardTitle: url.searchParams.get('rewardTitle'),
imageUrl: url.searchParams.get('imageUrl'),
seconds: Number(url.searchParams.get('seconds')) || 5 // default to 5 seconds
}
// Will subscribe to these events, mapped directly to the websocket subscription request.
window.streamerbot.subscribeTo({
Twitch: [ "RewardRedemption" ]
});
// Called when any event is received from Streamerbot, including those subscribed to by other scripts.
window.streamerbot.onMessage(message => {
if (
message.event.source === "Twitch" &&
message.event.type === "RewardRedemption" &&
message.data.title === config.rewardTitle
) {
showImage();
}
});
function showImage() {
// Create our image element
const imgElement = document.createElement("img");
// Modify the image element src to point at the configured image URL
imgElement.src = config.imageUrl;
// Append the image element to the HTML document
document.body.appendChild(imgElement);
// Set a timeout to remove the image after the configured amount of time
setTimeout(() => {
imgElement.remove();
}, config.seconds * 1000)
}
Now, to include our module in the HTML Overlay application, we must import it from the index.html document.
Open index.html in your code editor. (This file is also in the Content directory)
At the end of index.html, before the trailing </body> tag, add the following code to import our module:
<script type="module" src="show-image.js?rewardTitle=DEE&imageUrl=https://streamer.bot/logo.png&seconds=2"></script>
You'll notice that we are passing in our configuration options as parameters on the module URL.
// show the image when someone redeems our channel point reward named 'DEE'
rewardTitle: 'DEE'
// display the streamer.bot logo
imageUrl: 'https://streamer.bot/logo.png'
// show the image for 2 seconds
seconds: 2
Now that everything is ready to go, we can test by running HTMLWindowsOverlay.exe
Close HTML Overlay first if it is already running in the system tray
When you go to your chat and redeem the Channel Point Reward with the name DEE, you should see the Streamer.bot logo pop up on your desktop!