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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Styling Elements

Posted by Patricia Martin
Patricia Martin
5,477 Points

My code doesn't work properly...

I'm following the video steps but my code doesn't work properly. I used the console to see where the problem is and this is the message that appears: "Uncaught TypeError: Cannot read property 'addEventListener' of null at app.js:7"

const toggleList = document.getElementById("toggleList"); const listDiv = document.querySelector(".list"); const input = document.querySelector("input.description"); const p = document.querySelector("p.description"); const buttton = document.querySelector("button.description");

toggleList.addEventListener("click", () => { if (listDiv.style.display == "none") { toggleList.textContent = "Hide List"; listDiv.style.display = "block"; } else { toggleList.textContent = "Show List"; listDiv.style.display = "none"; } });

buttton.addEventListener("click", () => { p.innerHTML = input.value + ":"; });

Someone who can help me? I have reviewed the code a thousand times and I can not find the error :(

Thank you in advance!

2 Answers

Kieran Barker
Kieran Barker
15,028 Points
Kieran Barker
Kieran Barker
15,028 Points

Is it definitely an ID, not a class?

Patricia Martin
Patricia Martin
5,477 Points
Patricia Martin
Patricia Martin
5,477 Points

Oh, thank you thank you thank you!!! There was the mistake :S Now it works perfectly!

Kieran Barker
Kieran Barker
15,028 Points
Kieran Barker
Kieran Barker
15,028 Points

No problem. Also, are you sure all those constants are supposed to have those description classes in their selectors? That’s not what it looked like when I skimmed through the video. And you might want to change buttton to button :D