Cannot read properties of undefined (reading 'name')

[NIK03]

This is my code is there anything wrong with it?

 

let t1 = gsap.timeline({
  scrollTrigger: {
    trigger: element,
    start: 'top 70%',
    end: () => `+=${element.clientHeight}*2`,
    toggleActions: 'play reset play reset'

    // markers: true
  }
});
gsap.to(element, {
  scrollTrigger: {
    trigger: element,
    start: 'top 70%',
    end: () => `+=${element.clientHeight}*2`,
    toggleActions: 'play reset play reset',

    markers: true
  }
});

[GSAP Helper]

It's pretty tough to troubleshoot without a minimal demo - the issue could be caused by CSS, markup, a third party library, your browser, an external script that's totally unrelated to GSAP, etc. Would you please provide a very simple CodePen or CodeSandbox that demonstrates the issue? 

 

Please don't include your whole project. Just some colored <div> elements and the GSAP code is best (avoid frameworks if possible). See if you can recreate the issue with as few dependancies as possible. If not, incrementally add code bit by bit until it breaks. Usually people solve their own issues during this process! If not, then at least we have a reduced test case which greatly increases your chances of getting a relevant answer.

 

Here's a starter CodePen that loads all the plugins. Just click "fork" at the bottom right and make your minimal demo: 

See the Pen aYYOdN by GreenSock (@GreenSock) on CodePen

 

If you're using something like React/Next/Vue/Nuxt or some other framework, you may find StackBlitz easier to use. We have a series of collections with different templates for you to get started on these different frameworks: React/Next/Vue/Nuxt.

 

Once we see an isolated demo, we'll do our best to jump in and help with your GSAP-specific questions. 

[GreenSock]

This definitely looks problematic to me: 

end: () => `+=${element.clientHeight}*2`,

You've got the "*2" outside the {}, so if your element.clientHeight is 100, for example, it'd resolve to "+=100*2" which is not valid. 

 

I assume you intended something like: 

end: () => `+=${element.clientHeight*2}`,

Right?

 

Also, I'm not sure why you're creating a timeline that's empty (that won't do anything) and then a separate standalone tween which also isn't tweening anything. Maybe you meant to do this?: 

let t1 = gsap.timeline({
  scrollTrigger: {
    trigger: element,
    start: 'top 70%',
    end: () => `+=${element.clientHeight*2}`,
    toggleActions: 'play reset play reset'
  }
});
t1.to(element, {
  // some properties to tween?
});

(?)

 

A minimal demo will go a long way to getting you a solid answer. 👍