Automatic scrolling

Houge · 05-18-2017 02:18 PM

Hello!

I have a region for chat messages, i need to make my region auto scroll to last message at the bottom only if the scroll is at he bottom, and if i scroll up to read old messages it should not automatically scroll when new message appears.
If i check scroll position like this:

Code:

if(T.slidebar[1].offset() >= T.slidebar[1].lengthTotal() - T.slidebar[1].length())

{

    T.scrollY(9999, true);

}

It performs very bad with immediate=false, because it takes current position which != lengthTotal().

Maybe someone has an idea how to do this correctly? smile

P.S. It would be great to make it like build log in EE editor smile

Zervox · 05-18-2017 03:09 PM

To my knowledge scrollY() is a delta value, so 1 is max.
the code scrollY() scrolls with slidebar::scroll

I believe if you do
T.slidebar[1].scrollTo(T.slidebar[1].lengthTotal()); would equal the same but work with lengthTotal.

Houge · 05-18-2017 03:52 PM

Yes, but it doesn't do what i need.

Zervox · 05-18-2017 04:00 PM

the scrolling or the detection of how close it is to the end?

Houge · 05-18-2017 05:32 PM

When new message is added scroll only when i'm at the end.

**Esenthel** · 05-19-2017 12:54 AM

Editor uses this code:

Code:

SlideBar &sb=build_region.slidebar[1];

Bool at_end=(sb.offsetDesired()+sb.length()>=sb.lengthTotal()-0.02f);

if(at_end)build_region.scrollY(9999); // auto-scroll to the end

I will add this method to the SlideBar class:

Code:

Bool wantedAtEnd(Flt eps=EPS)C {return offsetDesired()+length()+eps>=lengthTotal();} // if slidebar is wanted to be at the end

Houge · 05-19-2017 05:28 AM

Thank you very much!

Automatic scrolling
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