On Sat, 5 Sep 2026 11:48:23 GMT, Marius Hanl <[email protected]> wrote:
> This PR fixes a Warning I always get when JavaFX and Swing are both mixed > together in an application. > The error: `XSetErrorHandler() called with a GDK error trap pushed. Don't do > that.` > > I attached a small reproducer to the ticket. It shows the sequence that must > happen for this error to appear: > > 1. JavaFX will call `gdk_error_trap_push` > 2. Swing will call `XSetErrorHandler` > 3. GDK will detect that the error handler is different from the one we pushed > > See also: > - > https://gitlab.gnome.org/GNOME/gtk/-/blob/gtk-3-24/gdk/x11/gdkmain-x11.c#L313 > > --- > > Checking the Swing code, we just call `XSetErrorHandler` and not > `gdk_error_trap_push`. See also: > > - [Swing > XlibWrapper](https://github.com/openjdk/jdk/blob/master/src/java.desktop/unix/native/libawt_xawt/xawt/XlibWrapper.c#L1328) > - [Swing > gtk3_interface](https://github.com/openjdk/jdk/blob/master/src/java.desktop/unix/native/libawt_xawt/awt/gtk3_interface.c#L679) > > `gdk_error_trap_push` will call `XSetErrorHandler`, so we might as well do > that directly. > I checked the code in `gdk_error_trap_push`, I do not see any problems with > this approach. > > From what I understand, `gdk_error_trap_push` is meant to be short-lived, so > should be popped soon with `_gdk_error_handler_pop`. `XSetErrorHandler` makes > more sense as a 'long-lived' option, and it does the same for our usecase, > that is to not make the application exit on any `gdk_x_error`. > > cc @tsayao, a review is appreciated. > > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai). Suggestion modules/javafx.graphics/src/main/native-glass/gtk/GlassApplication.cpp line 59: > 57: static int glass_x_error_handler(Display*, XErrorEvent*) > 58: { > 59: return 0; Maybe print the output of [XGetErrorText() ](https://tronche.com/gui/x/xlib/event-handling/protocol-errors/XGetErrorText.html) in DEBUG builds? ------------- PR Review: https://git.openjdk.org/jfx/pull/2296#pullrequestreview-5713513546 PR Review Comment: https://git.openjdk.org/jfx/pull/2296#discussion_r4424511708
