TimelineMax remove : further details please

[Thomas James Thorstensson]

Hello There. Hows it going?

 

 

In a banner project I'm working on I see this used where 'tl' is an instance of TimelineMax

tl.remove(tl.getChildren()[tl.getChildren().length-1])

Hmmmmm. That is slightly different to the api explanation:

 

.remove()

.remove( value:* ) : *

Removes a tween, timeline, callback, or label (or array of them) from the timeline.

 

Hmm....

 

Question, what can the previous coder be up to by the first line of code. Can you feed it multiple arguments?

 

Hmmm...not sure where I am, is this the way to the coffe machine?

 

 

Thankful for reply

 

 

.t

[OSUblake]

It's removing the last child. The syntax is probably throwing you off, but there's only 1 argument there. This is what it's doing...

var children = tl.getChildren(); // Returns an array
var i = children.length - 1; // Index of last child in array
var lastChild = children[i]; // Set variable to last child in children array

tl.remove(lastChild);

The user called getChildren() the second time just to get the length of the array. Probably not the most efficient way to do it, but it works.

[Thomas James Thorstensson]

Thanks for your swift reply,

 

yes I understand that that will fetch the last child in the array. But what I don't understand is why he first fetches the entire array, then fetches the last child.

 

I mean, there are two calls to getChildren():

tl.remove(tl.getChildren()[tl.getChildren().length-1])

I am not sure what is happening under the hood: Is tl.remove first removing based on tl.getChildren() - and then a second time removing based on [tl.getChildren().length-1]

 

Many Thanks

 

.t

[GreenSock]

You're right about it being unnecessary (wasteful in fact) to call getChildren() twice like that. Blake did a great job of explaining what that line was doing and that it wasn't two parameters. It's not very readable (the original, not Blake's). The original could be simplified to:

tl.remove( tl.getChildren().pop() );

That just grabs the children as an array and pop() will grab just the last one from that array, using it as the parameter for remove(). 

 

Does that clear things up?