On Fri, 11 Sep 2026 15:14:08 GMT, Marius Hanl <[email protected]> wrote:
>> Something I found out while experimenting in >> https://github.com/openjdk/jfx/pull/2051. >> It was on my list to do since then. >> >> The `VirtualFlow` can end up creating 1-2 unnecessary cells, which then are >> never used. They just sit in the pile. >> This happens because we may end up calling `addLeadingCells` although our >> first cell is already on position `0`, so at the top - there is no cell >> above us. >> >> In this scenario, we do not need to call `addLeadingCells`. >> >> Also added the optimization I found in the PR mentioned above. >> When we have 10 visible cells, size 25px and scroll 10px, we will have 11 >> cells visible. >> If we scroll to the top again, we will have 10 cells visible again -- and in >> this case we will remove it from the `sheet`. >> But the pile could contain even more piled cells (e.g. when the application >> size got smaller, we have less cells to render, all remaining cells went >> into the pile). >> So the removal is a bit faster with that method, instead of always calling >> `removeAll`. Same functionality. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Marius Hanl has updated the pull request incrementally with one additional > commit since the last revision: > > bulk remove modules/javafx.controls/src/main/java/javafx/scene/control/skin/VirtualFlow.java line 2855: > 2853: wasFocusOwner = wasFocusOwner || doesCellContainFocus(cell); > 2854: cell.setVisible(false); > 2855: there might be a problem: - cell.setVisible(false) invokes a listener that let's say, scrolls and removes the cell from pile, then reuses that cell for a different index synchronously. - the said cell is active, but later code removes it in L2861 the old code removed the pile after all the callbacks were done in L2855 ------------- PR Review Comment: https://git.openjdk.org/jfx/pull/2308#discussion_r4008695749
