Trigger function when someone has stopped typing for 1 second

Question

I have an input field which generates auto suggestions when someone starts typing. The user does not need to blur or hit a submit button for the suggestions to appear. When someone has stopped typing I would like to run a function for tracking which products were shown to the user, along with the string of text currently in input field. I added an 'input' event listener but I cannot get my logic right. I want to `doStuff()` if it has been at least 1 second since the previous input event. Trouble is that my script is firing when a user starts typing not after since it's based on 'change' event listener. And I'm thinking there must be a more logical way than I'm doing now. Also I'm worried that 'input' event is impacting the users browser since it's running on every keystroke, maybe there's a better way? Reluctantly showing my code block below even though it does not make much sense and is one of my weaker scripting moments, more showing that I have been trying different things. Would p…

Accepted Answer

You can use the `input` event listener together with `setTimeout()` and `clearTimeout()` as follows:

```
var timeoutID;

document.querySelector('#search_input').addEventListener('input', function(e) {
  clearTimeout(timeoutID);
  timeoutID = setTimeout(function() {
    alert("1 second has passed since any input was received.");
    // doStuff()
  }, 1000);
});
```

```
<input id="search_input">
```

The `setTimeout()` function queues up the function you pass it in the first argument to be executed after the specified number of milliseconds have passed. The `clearTimeout()` function cancel a currently scheduled timeout based on the id returned by `setTimeout()`.

So the function I've shown above basically says that whenever an `input` event occurs, cancel any previously scheduled timeout and then create another. Thus the code in the inner function will only be run approximately 1 second after the user stops typing.

Trigger function when someone has stopped typing for 1 second

Solution

Problem