No scrolling glow on Android

Original issue 738 created by codenameone on 2013-06-12T07:40:16.000Z:

When i use a ContainerList filled with rows, i don't see the blue glow when reaching the end of the list (i actually see a really small bit of it, 2 px maybe). It looks like the glow is not showing on top of everything but under de rows.

What steps will reproduce the problem?

• Add ContainerList to the screen
• Add enough rows to be able te scroll
• Set some background image / color on it

What is the expected output? What do you see instead?
Expected to see a blue glow when reaching the end of the list
I see about 2px of blue and i strange little bounce of 2 px.

What version of the product are you using? On what operating system?
Using latest CN1.
Android 4.1.2 on Samsung Galaxy Note 2

Comment #1 originally posted by codenameone on 2013-06-12T08:33:49.000Z:

I'm not sure it should be on top. We normally have 2 additional pixels or so at the bottom to show the glow thru if the UI isn't transparent.
Is it possible you have nested scrollables?

Comment #2 originally posted by codenameone on 2013-06-12T08:49:21.000Z:

When you open a native android app which has a list in it you could very clearly see how the glow should behave when scrolling to the end.

In CN1 this is not correct. See the screenshot for current situation. It is hard to see but there is a little blue overscroll in the top.

https://www.dropbox.com/s/a8aya1dx9kopt5n/Screenshot_2013-06-12-10-35-19.png

This is as it should be:
http://i1075.photobucket.com/albums/w435/zhp_pilot/Rezound/ICICS/neomax_overscroll_glow.png

So no bounce at all, and the glow about 5 mm.

Note: i use nativebool in theme settings

Comment #3 originally posted by codenameone on 2013-06-12T08:55:43.000Z:

FYI You can attach images here instead of using links which might not exist in the future (when we review past issues).
Looking at the code it is painted on top, I'm not sure why you are seeing the issue but I just tried this with an app and it looks fine. It sounds like you are nesting scrollables and the effect just doesn't happen.

Comment #4 originally posted by codenameone on 2013-06-12T09:06:32.000Z:

For me it looks like i don't nest scollables, i attached a part of my theme so you can check how it is set-up.

Comment #5 originally posted by codenameone on 2013-06-12T10:50:06.000Z:

Assigning this to Chen to evaluate further.

Comment #6 originally posted by codenameone on 2013-06-12T13:12:44.000Z:

Assigning back to Shai, it's a native theme issue the painting is performed above just fine the blue glow is simply too thin compared to the native android one.

Comment #7 originally posted by codenameone on 2013-06-12T13:22:36.000Z:

I took the graphic from Googles repository so I'm not really sure how to help you if this is indeed the case. You can easily replace the graphic using the Codename One designer.

Comment #8 originally posted by codenameone on 2013-08-07T19:15:55.000Z:

I see the source of my confusion here. There are two images, one is for the edge which we are doing mostly correctly and a separate one for the glow:
https://github.com/android/platform_frameworks_base/blob/5cb0f2184656642160e9ac032d0646f766058a5b/core/java/android/widget/EdgeEffect.java

https://github.com/android/platform_frameworks_base/blob/master/core/res/res/drawable-xhdpi/overscroll_glow.png

https://github.com/android/platform_frameworks_base/blob/master/core/res/res/drawable-xhdpi/overscroll_edge.png

Currently we only incorporate the edge effect and not the glow effect. I'll have a look at adding that option too.

Comment #9 originally posted by codenameone on 2014-02-24T08:27:41.000Z:

This is fixed to the best of our ability now, there are still some differences but they are deep in the logic of the UI.