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addKeylistener() not working
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I am making an RPG game in Java using my Swing-based engine, and everything works on my FreeBSD as well on Linux, but on Windows it seems like the keyboard handler is broken. I have no idea why it happens, the same JAR file works good on Linux/BSD.
I have no source why does this not work as no error popups in the console and everything runs as expected except for the key input.
The game is too large to provide source scraps here (I have no idea what is wrong), but it is on my git: http://codeberg.org/glowiak/gnengine
Package com.glowiak.gnengine contains the engine, com.glowiak.myrpg contains the game and that's all worth noting.
I tried switching JREs but nothing did fix it, on Linux OpenJDK ran it fine, on Windows it did not.
On windows, if you click the game window, then press the Tab key, the controls then work. This is because when you press the the Tab key, you are setting the focus onto your JPanel, which is required for a Key Listener to work properly in java swing. For more details, see this answer by hovercraft full of eels.
My recommendation would be to follow the advice of that answer, and instead of using KeyListeners use KeyBindings.
Related
I installed Eclipse IDE for Enterprise Java Developers 2020-09 with WindowBuilder 1.9.4. Then I tried to create a test application: SWT/JFace Java Project with a JFace ApplicationWindow.
My problem is that I cannot drop anything on the window directly in design mode. It is possible to add widgets to the main container in the components tree. But they seem to be hidden behind the parent shell (I could see this from setting a background color for it and when I add them I can see their bounds, but then no longer). It is not possible to resize the application window in design mode either.
However, when I do "Test/Preview...", the widgets are there. And also when I run the program, as they should as they are in the code. In the latter case also the resizing works (not with "Test/Preview..."). The resizing seems to work at first, but then it snaps back to a minimal size where only the menu and toolbar fit in the window,
This is so with any such project. I first tried to import a program I had written in an older version of Eclipse. There I have tabs in a composite in the container. They seem to be hidden, too (and misplaced, also behind the toolbar). But when I run the program, everything is fine. I first thought I might have messed something up in the program, so parsing gets sidetracked. But that cannot be it as the problem already arises in the simple test program where I have just one widget and the default code.
I have tried quite a few things to get around this, eg. reinstalled the IDE, installed an older version, installed an older version of WindowsBuilder in case this is a bug in either. But to no avail. Has anyone experienced the same problem? Seems like there is a simple mistake on my part. Something I would have to change in the settings or maybe the program?
But I have no idea where to look. Could it have to do with the JRE (OpenJDK15U-jdk_x64_windows_hotspot_15_36)? Had to take that as the download from Oracle does not work for some reason. There is a warning that it is not exactly compatible. But then the program works fine, so it cannot be at such a basic level? Any ideas very much appreciated as I am totally stuck at this point.
There is no problem with designing eg. a JFace dialog. Everything works as expected, I can drop widgets, resize, etc.
Here is how it looks:
Brute force "workaround": I go back to Oxygen where things are working fine. But somewhat of a defeat because I am stuck with an old version, which is a deadend. IIRC already going to Photon posed insurmountable problems for me (certainly my fault as I am not that good at the nitty-gritty). Would still be very interested in an answer to my question. Urgency is now lower as I can at least keep working on my program and let my frustration die down after two days of futile attempts.
[Edit: I only tried the resizing in Oxygen 32-bit, that worked, but did not check whether the problem with dropping a widget on the application window was also there. Then I tried to get the 64-bit version to run, which I could not do. There is apparently a problem with Java > 8. Installation of Photon worked finally. However, while resizing is okay there, I get the same problem with dropping widgets and that they appear to be misplaced (upper left corner of the area seems to be behind the toolbar. The "workaround" unfortunately went nowhere. So I am again more interested in an answer than I thought.]
[Edit 2 as per Oct 12: Since I could not solve this problem, I decided to redo the GUI with a SWT Application window. That lacks some of the functionality of a JFace Application window (I especially miss the ease of Actions). So it seems like a step backwards, and it caused some extra effort. But then the upside is that I had to rethink a few things about the structure anyway, which means I was forced to do that sooner than later. But still would like to get also JFace Application windows to run. Pressure is no longer there, but out of interest what went wrong.]
Short history of problem:
After upgrading to Ubuntu 15.10 I had some problems with any Qt-apps after durable work with IntellijIDEA. In apps like tortoisehg I saw painting problems, like not filled areas or shifted text. It was fixed after reading post in archlinux forum. Just set up property for Qt and changed my openjdk to oracle's.
The next story, that possibly is relative to first, consists in my work in IntellijIDEA and other Java swing applications (like Netbeans RCP): after long term working some dialogs became transparent, were inaccessible or just clicked through it to something under. Reopen of the dialog or window helps, but my colleagues have same problems on other OS, like Fedora (with KDE).
This bug is annoying, because our product is written on Netbeans and works under *nix distributive. Sometimes we stuck with problem of click-through problem: dialog or window just clicked into window after it.
I think the problem in wrong settings of x-server and in Qt- and Java- toolkit clash. This leads to artifacts on both application groups.
Does anybody stuck with this problem and do you have some ideas to resolve it?
The possible reason is described in Russian here (https://toster.ru/q/267833?e=3090918#clarification_329784).
Some bugs of it are found in:
https://bugs.kde.org/show_bug.cgi?id=350976
https://bugs.launchpad.net/ubuntu/+source/openjdk-7/+bug/1512760
Summary: the Java and Qt applications use shmem that is never cleaned by Java, after some time Qt cannot use this memory to work right. Google it with words «Java Qt shmem».
I have recently started to notice that when clicking on some components like MenuItems in a MenuBar, or Choicebox that before they actually show up it takes about 2 seconds.
I would click on a choicebox and then wait 2 seconds before the choicebox items come up. This is also with components from third party libraries like ControlsFX.
The strange thing is that this is for ALL java applications that use JavaFX. Not just my application so a bug on my end is out of the question. I have tried uninstalling all java versions and installing a lower version to no avail.
My current java version is 1.8.0_45 (JDK) x64 on a Windows 8.1 Pro x64.
I am certain it is not my computer that is not performing well.
EDIT:
There is litterally nothing that I could find on this matter. I tried asking the Java Community on their website but my post got deleted for an unspecified reason.
EDIT 2:
After some research I have noticed that java puts error entries in the windows event logbook http://prntscr.com/6vnlww (sorry it's in dutch) and please look below in the comments for a ProcMon dump of everything that happened between me clicking on a choicebox in java and the choicebox opening up the item choices.
I've written a Java database program using Swing, and it looks and works fine on my Windows machine. I was expecting to be able to transfer it to my Linux (CentOS 6) machine with no problems, and while it compiles and runs just fine, the GUI is blank.
Specifically, a JDialog that I show appears as a solid grey rectangle, but I can still see my cursor change to an I bar when I hover over the text boxes, and I can type into them and press the invisible Ok button, and it works. (This is a database login dialog.)
Then, a JFrame that I've setup as an MDI parent is displayed, but it has zero size. If I drag it open it does have a border, but it does not visibly have the menu that I placed on it. I don't seem to be able to access the menu invisibly as I was able to on the JDialog.
I suspect that this must have something to do with some Java or library version, but I'm not sure. I tried installing Java 7 but it didn't change anything. I'm not sure if I should uninstall Java completely and try reinstalling it, or if maybe it has something to do with the project instead (I am using Eclipse Kepler if that helps.)
I see a few other "Java program is blank" questions, but they either do not have answers or are not the same issue I am having. (My program is only blank under CentOS so far; it works and looks just fine under Windows.)
I narrowed it down to a single line. In the JDialog I had the following:
setType(Type.POPUP);
as soon as I removed this line, the dialog became visible.
Additionally, I find that if I use the Test/Preview... feature (this is using the WindowBuilder) when that line is present, it shows the dialog blank, but it is non-interactive and effectively hangs Eclipse. This led me to "end-task" java.exe, which did unfreeze Eclipse, but it ended up causing even more problems, including the ones I was having with my MDI JFrame.
After rebooting, and removing the above POPUP line, everything is working great.
I have developed a java program that runs fine in Mac OS X (10.6.7).
But if I click on another window such as Finder or another application, my program freezes, or the graphics are not updated anymore. If I click on my program again the graphics are updated again and runs well.
Does anyone know what that can be?
I coded it with the LWJGL and slick libraries.
Thanks!
Taken from here:
By default slick will not render anything if it does not have focus,
so good practice for applets is to set
container.setAlwaysRender(true);
so that it always renders even when it doesn't have focus.
This seems to refer to GameContainer.setAlwaysRender. Although the forum post talks about applet, both AppGameContainer (standalone-application) and AppletGameContainer.Container extend from it.