On Sat, 13 Sep 2025 17:54:08 GMT, John Hendrikx <jhendr...@openjdk.org> wrote:
> Fix for regression in TabPane size calculation caused by > https://bugs.openjdk.org/browse/JDK-8350149 (#1723) between versions 25-ea+8 > and 25-ea+10 > > In Region several height calculations functions were altered to match the > behavior and options of their horizontal counterparts to solve discrepancies > between the behavior of vertical biased layouts and horizontal biased > layouts, which other than their axis, should behave identical. > > The height calculations would take a width provided by the caller, but if > unavailable (set to -1) and the child was biased, it would just automatically > query the child's preferred width and use that as the dependent width. > > In contrast, the horizontal functions would only do this if a height was > provided by the caller (not -1), and would only override this value if the > property fillHeight was false (in which case it would query the child's > height directly). > > With the change in > [JDK-8350149](https://bugs.openjdk.org/browse/JDK-8350149), the vertical > calculations operate the same as the horizontal ones, as this is generally > more flexible. However, the automatic behavior to query the child's size if > the dependent size given was set to -1 is no longer there (as this behavior > isn't how biased calculations should work). > > The TabPaneSkin has chosen to directly call several width/height functions > without obeying the content bias contract, which says that in case of bias, > the dependent size must be calculated first and then passed to the size > calculation one is interested in. > > (As an aside, if TabPaneSkin had elected to put all tabs in a single > StackPane, then StackPane would have correctly done these calculations, but > digging into why it is done this way, with each individual Tab wrapped in its > own Node (also a StackPane), is a bit out of scope for this fix). > > As it is, TabPaneSkin should check the bias of the tab it is doing > calculations for, and if biased, should first query the dependent size before > triggering the size calculation it is interested in. Reviewers: @arapte @andy-goryachev-oracle ------------- PR Comment: https://git.openjdk.org/jfx/pull/1900#issuecomment-3292700722
