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JavaScript JavaScript and the DOM Making Changes to the DOM Change Element Attributes

Keith Grimes
Keith Grimes
10,263 Points
Posted by Keith Grimes
Keith Grimes
10,263 Points

Getting "null is not an object (evaluating input.value).

When I try to run this code, I keep getting the error message. What am I doing wrong?

btnUpdate.addEventListener("click", () => {
    const headline = document.getElementById("headline");
    const input = document.querySelector(".input-main"); // this variable is local and only accessible by this function

    headline.textContent = input.value; // input.value returns whatever is typed into the input text field
    input.value = ""; // this clears the text from the input field textbox  
    headline.className = "grow"; // this applies the CSS class "grow" to the headline element node
});

1 Answer

Brian Jensen
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree seal-36
Brian Jensen
Treehouse Staff
Brian Jensen
.a{fill-rule:evenodd;}techdegree seal-36
Brian Jensen
Treehouse Staff

Hiya Keith Grimes :wave:

It appears that you're just missing the btnUpdate variable declaration from the starter workspace for the video:

const btnUpdate = document.querySelector('.btn-main');

Awesome code comments! :fire: