In G2, scrollView is not that smooth?

Solar2D Advanced Graphics
#21

Just test with the latest build 2178, 

scrollView choppiness problem still exists.

#22

I agree with all of you. This issue is a big deal especially when it comes to building business apps… I am sure the corona dev’s notice/know about the jerkiness/performance issue of scrollView/tableView - hopefully they can start focusing on that more because this eventually could be a showstopper for a lot of people trying to build business apps with corona.

#23

I also experience choppiness with scrollview.

I have the entire canvas scroll vertically (there are several graphics in the scrollview, but no buttons or clickable objects) 

    scrollView2 = widget.newScrollView{

    width = 1140,

    height = 900,

    scrollWidth = 0,

    scrollHeight = 1140,

    horizontalScrollDisabled=true,

    hideScrollBar =true,

    backgroundColor = { 205/255, 251/255, 255/255}

}

When scrolling up or down, every once in a while it “jumps”.

This didn’t happen in G1.0 I have the latest build

Jorge

#24

Exactly what I am experiencing & it’s the reason I created this post.

It’s really weird that only you & me feel the same for the G2 scrollView.

I could feel it right after I migrated to G2.

It’s still the same with the latest build.

#25

I’ve experienced a lot of issues with G2 (choppy storyboard transitions, slow preloading of images, choppy scrollview, etc).

But my apps are heavy in graphics (lots of images, animations, and sounds) and this is perhaps why I am experiencing these issues and others don’t.

The thing is, my app was smooth in G1 : /

#26

Any solutions to this issue or comments from corona staff?

#27

Is this an issue where you scroll over the top edge and before it snaps back try to scroll down again?

If it’s something else please try post a short sample that shows this and explain what you do to make it jump and I might be able to help you get a quick fix.

#28

Currently, this is just more of a nuisance. We have optimized all of the images that come from our DB to the exact size they appear in the feed and that has helped considerably. However, even with all the images optimized and sized properly, if you scroll the content as it slows down it jerks or appears choppy and at certain speeds it jerks. Just doesn’t look smooth, consistently.

@Joe528 comments above describe a similar issue we are experiencing almost perfectly. 

I suppose my question is…

  • is it possible to achieve native-like scrolling with Corona? That is smooth and consistent?
  • is it some code/image optimization that we need to do on our end, OR is it simply related to G2.0?
#29

I know there are some scrollView fixes coming.  I don’t know if this one is addressed or not. 

Rob

#30

Thanks @Rob, that is really good news. Hopefully, the update will correct the issue.

#31

Ok, I filed a bug report for this problem, case 30976.

Attached is the code to test with. There is nothing but a scrollView with 20 text items.

Although it happens in Simulator too, it happens more often & obvious in actual devices. Besides, with actual devices you can swipe faster & it’s how the end users operates.

Try to scroll up & down, sometimes go fast, try to bang on it.

You should be able to feel sometimes it’s just not that smooth & jumps a bit here and there.

#32

I tried it in the sim and on my iPhone 5.  It seems pretty smooth to me.  Can you make a video?

Rob

#33

I will see if I can make a video.

But just try to move fast enough between ups & downs 

and when you swipes, lift your finger up right away

You should be able to see it. It’s quite obvious.

#34

This are two separate issues.

What joe528 is experiencing is when you scroll fast and it hit’s limit then before it bounces back scroll in the other dirrection again. This will cause it to jump to the begining at the time that bounce back was supposed to complete.

This could be fixed by canceling bounce back if there was another touch.

The other issue is that you can see when momentum scrolling slows down that it’s not smooth. This is not just a scrollview issues. It’s any transition, enterFrame update (which is what momentum scrolling is) and alike. If you are doing things in enterFrame or timers that take various amount of time in each frame than you will see this.

Primoz

#35

@primoz.cerar

In your earlier post, you said you could fix the first issue? How?

#36

By taking the GitHub source for scrollview and fixing the bounce back to cancel on another press. But you would have to use that version in your project. You can use only one file that is the culprit which is ‘widget_momentumScrolling.lua’. And the rest would be used from the builtin version which has some bug fixes already compared to the version on GitHub. I will look into it in the event and post the fix.

#37

Do you mean the fix is already in or you are going to look into it?

#38

I will look into it and post the fix in the evening. (Typo in last post)

#39

Here is what I came up with. It needs some testing to make sure everything is ok.

Just unzip with the folder in the zip in to you project dir.

Now if you want to use the scroll view or the table view with the fixes do this:

local widgetFix = require (“widgets.widget”)

local scroll = widgetFix.newScrollView(options)

same for table view.

If you need any other widgets include the default corona ones like you always do:

local widget = require (“widget”)

Included fixes:

  • scroll view will not jump back to starting position if scrolling in opposite direction before bounce back has completed (vertical and horizontal)

  • eliminated occasional error when removing objects from scroll view

  • exposed scrollView:updateScrollAreaSize() for making sure the scroll works correctly when moving objects inside the scroll view

  • fixed some issues when using multiple scroll views at the same time

  • scroll view and table view now respect the vertical scrolling threshold

  • fixed table view bug when deleting multiple rows

  • fixed table view insertRow bug that says table view is scrolling when it’s not and doesn’t allow insert

  • fixed scroll view scrolls to top when inserting objects issue (pass keepPositionOnInsert = true in newScrollView)

  • fixed tableView:scrollToY doesn’t stop scrolling

Hope this helps. Let me know if there are any issues.

#40

Awesome, this is great work! Now, if you could sneak in preventing scrollView to shift back to top after inserting objects (http://forums.coronalabs.com/topic/41639-20132087-widgetnewscrollview-scrolls-to-top-when-inserting-new-items/#entry233284) you sir, would forever be held in my heart. lol