On Thu, 8 Jun 2023 03:12:49 GMT, Sergey Bylokhov <s...@openjdk.org> wrote:
> > > > > We should check why that code does not work, note the code in that > > > > > patch also support both Window and Canvas. > > > > > > > > > > > > We can use `getAppropriateGraphicsConfiguration()` of `XCanvasPeer` > > > > class, which solves the problem. We can use it whenever new screen is > > > > set/new screen GC is set (Not sure of why it wasn't used before). The > > > > old code gets defaultGC whenever screen switch happens. We can use the > > > > existing implementation, which is actually better than selecting > > > > TransparencyCapable GC alone. Their exist a regression for this re-use > > > > solution i.e., test > > > > [WindowGCChangeTest.java](https://github.com/openjdk/jdk/blob/master/test/jdk/java/awt/Multiscreen/WindowGCChangeTest/WindowGCChangeTest.java), > > > > which is basically windows specific test. > > > > > > > > > If think that method should work even before the fix. In the peer we set > > > the GC to some value we found, then call > > > Component.setGraphicsConfiguration() which for canvas and window should > > > call getAppropriateGraphicsConfiguration. Why it does not work? > > > > > > In Window, GC is set when during initialization, i.e., `initGC()` is > > called, also there is separate `setGraphicsConfiguration() ` method. But > > unlike `Canvas.setGraphicsConfiguration()`, in window > > `getAppropriateGraphicsConfiguration()` is not used. So with Window, unlike > > Canvas setting a GC is quite different and doesn't involve > > `getAppropriateGraphicsConfiguration()` I hope. > > So this bug is not reproduced for Canvas? Then probably we should use the > code similar to Canvas.setGraphicsConfiguration in the WIndow class? Can't be sure of both. Because `getAppropriateGraphicsConfiguration()` is used only if initialization of GC during `initGC` fails, i.e., `GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().getDefaultConfiguration();` fails to load GC. Moreover in this bug we are trying to address the switch over between screen, hence my fix is in Peer component. So adding a similar code in Window class might not be a fix, rather we **might** have to change the way GC is loading from initialization too. ------------- PR Comment: https://git.openjdk.org/jdk/pull/14246#issuecomment-1582088539
