> This PR fixes an issue which is probably in JavaFX since VirtualFlow exists. > While horizontal scrolling any VirtualFlow control the left blue border > sometimes disappear/gets smaller. (see also image below) > > This can be fixed by **snapping** the scroll bar value (similar like e.g. a > **ScrollPane** does). > The same needs to be done on the table header as otherwise the column lines > might be 1 px off to the cell lines. > As a side effect this also fixes that the column lines sometimes get's blurry > when horizontal scrolling (see second image). > > While testing with **-Dglass.win.uiScale** I found out that the problem is > not fixed for a scale like 1.25 or 1.5, while it is fixed for 1 or 2. The > border sometimes disappears only when the snapped value is a decimal number > (which obviously does not happen on a scale of 1 or 2), e.g. something like > 12.6 but it will never disappear when it's a normal number, so e.g. just 12. > > That's why something like **Math.round(..)** or just a **cast** to an **int** > instead of snapping fixes this problem for all scales. I also didn't notice > any side effect. But not sure if this the right fix then. > How does JavaFX render a **node** when e.g. the x is a decimal number? And > does a decimal number make sense (Why we e.g. don't round the value)? > > Another explanation could also be that there is an issue somewhere deep > inside the node layout/snapping/Clip/Group/pixel rendering and to simply > round/cast the value just fixes the symptom here. > > In any case I'm open for any feedback, help or explaination. > I'm also glad for anything which might help identify the root cause here, if > any. > > --- > 1. >  > --- > 2. > 
Marius Hanl has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains two commits: - Merge branch 'master' of https://github.com/openjdk/jfx into 8218745-snapping-x-y-tableview-scroll Conflicts: modules/javafx.controls/src/test/java/test/javafx/scene/control/TableViewTest.java modules/javafx.controls/src/test/java/test/javafx/scene/control/skin/VirtualFlowTest.java - 8218745: Snapping X/Y when scrolling ------------- Changes: https://git.openjdk.org/jfx/pull/630/files Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=630&range=01 Stats: 60 lines in 6 files changed: 56 ins; 0 del; 4 mod Patch: https://git.openjdk.org/jfx/pull/630.diff Fetch: git fetch https://git.openjdk.org/jfx pull/630/head:pull/630 PR: https://git.openjdk.org/jfx/pull/630
