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JavaScript Object-Oriented JavaScript (2015) Practice Project User Interface Code

Posted by John Bastian Bolhano
John Bastian Bolhano
4,800 Points

Cannot set property 'innerHTML' of null

I tried to copy what's in the video but my code doesn't work.

https://w.trhou.se/7c6efvu6dx

It outputs an error like this

quiz_ui.js:31 Uncaught TypeError: Cannot set property 'innerHTML' of null
    at Object.populateIdWidthHTML (quiz_ui.js:31)
    at Object.displayProgress (quiz_ui.js:42)
    at Object.displayNext (quiz_ui.js:11)
    at app.js:18

quiz_ui.js:31 Uncaught TypeError: Cannot set property 'innerHTML' of null
    at Object.populateIdWidthHTML (quiz_ui.js:31)
    at Object.displayProgress (quiz_ui.js:42)
    at Object.displayNext (quiz_ui.js:11)
    at HTMLButtonElement.button.onclick (quiz_ui.js:37)

3 Answers

Natalie Cluer
Natalie Cluer
18,899 Points

Hi! when you call the function, you misspelled the id. you have "progess" instead of "progress".

John Bastian Bolhano
John Bastian Bolhano
4,800 Points

Thank you for the help. How did you find the error?

Natalie Cluer
Natalie Cluer
18,899 Points
Natalie Cluer
Natalie Cluer
18,899 Points

A lot of the time when there is an error setting the property it is because you are trying to set something that the JS program cannot find. The first place I usually look is where the function is called and follow the trail from there.

John Bastian Bolhano
John Bastian Bolhano
4,800 Points

Thank you for the suggestion. I saw another problem and did follow what you have suggested and it works. Thanks again!

Natalie Cluer
Natalie Cluer
18,899 Points
Natalie Cluer
Natalie Cluer
18,899 Points

no problem! Happy coding!:)