Why does Java resize a Window to 1x1 pixel when HDMI is unplugged (and does not resize back when HDMI is plugged)

[Martin Petzold]

I have a Java application running on:

XWayland 2:1.20.11-1+deb11u6, Weston 9.0.0-1, OpenJDK 
11.0.18+10-1~deb11u1, Debian 11, Kernel 5.10.52

My JFrame (Window) is set 
to:|GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().setFullScreenWindow(this);|

I can then see my interface on the full screen (in my case it is a TV 
and I have CEC enabled in the Kernel). However, after I unplug HDMI and 
plug HDMI again, my interface is gone (black screen). There is only one 
small 1x1 pixel left. It seems the size of the Window is changed by Java 
/ XWayland / (Weston). I am sure, that I am not changing it - I check 
all resize methods on JFrame.

When I restart my Java application, it is back again - so it is not an 
issue of the OS (Linux) directly and also - most probably - not Weston.

I also don't have this issue with a pure Wayland application (e.g. 
Weston flower). Using only Wayland (without Java and XWayland) things work.

When I PLUG the HDMI there is NO java.awt.event.ComponentEvent

When I UNPLUG HDMI, I get the following java.awt.event.ComponentEvent:

|java.awt.event.ComponentEvent[COMPONENT_RESIZED (0,0 1x1)] on frame0 
java.base/java.lang.Thread.getStackTrace(Thread.java:1602) 
java.desktop/java.awt.AWTEventMulticaster.componentResized(AWTEventMulticaster.java:167) 
java.desktop/java.awt.AWTEventMulticaster.componentResized(AWTEventMulticaster.java:167) 
java.desktop/java.awt.Component.processComponentEvent(Component.java:6461) 
java.desktop/java.awt.Component.processEvent(Component.java:6415) 
java.desktop/java.awt.Container.processEvent(Container.java:2263) 
java.desktop/java.awt.Window.processEvent(Window.java:2049) 
java.desktop/java.awt.Component.dispatchEventImpl(Component.java:5011) 
java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2321) 
java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2772) 
java.desktop/java.awt.Component.dispatchEvent(Component.java:4843) 
java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:772) 
java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721) 
java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715) 
java.base/java.security.AccessController.doPrivileged(Native Method) 
java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85) 
java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95) 
java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745) 
java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743) 
java.base/java.security.AccessController.doPrivileged(Native Method) 
java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85) 
java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742) 
java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203) 
java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124) 
java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113) 
java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109) 
java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) 
java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90) |

Unfortunately I also don't know how to manipulate the size after I 
catched this event. I tried to directly set the size back, but this did 
not work. I think it may don't work because at this time HDMI is 
UNPLUGGED. Also, if I try to set the size back to normal once the HDMI 
is plugged again, it does not work. I get overruled and the size is then 
back to 1x1 pixel.

As I don't get any event when the HDMI is PLUGGED again, I also don't 
know when to (try to) set the size back to "normal".


Thanks,


Martin
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/jdk-dev/attachments/20230609/b40b9a7e/attachment-0001.htm>