Strange Java Issue

Update

See below for the solution. Spoiler – It’s a typo.

Back in April 2020, I wrote a little program to run a sequence of LibreOffice Impress Slide shows. For ease of deployment on Windows and Linux, I built the program in Java. And it worked just fine. Here’s what the program looks like:

You can follow the whole Saga of its development using this link. The program has been working very well on Linux Mint 19 and 20 and Windows 10 for a couple of months now. I’ve not changed anything since May 16. Here’s the github repository.

Continue reading “Strange Java Issue”

Ubuntu 20.04 My First Look

Ubuntu Desktop 2020-04-29 22-18-33
Ubuntu 20.04

So, Ubuntu 20.04 just released, and there are a ton of Youtube videos reviewing it. After the debacle of file sharing between Linux Mint 19.3 and Windows, I decided to make a VM [Virtual Machine] with Ubuntu 20.04 to see if it had fixed the problem. The short answer is, alas, no. Guess Ubuntu will get the fix when it’s ready, and I’m sure the fix will be back ported to LM 19 when it releases.
Years ago, I used Ubuntu for a time, before Linux Mint came out. It was pretty clunky, but a lot less clunky than SUSE which is what I started with years ago. Things have come a long way. Of course, Mint is based on Ubuntu, but they are very different experiences. This is a diary of sorts of my experiences while I was testing the file sharing problem and setting up Ubuntu to my liking.

Continue reading “Ubuntu 20.04 My First Look”

Linux to Windows File Sharing Issue

So, reaching a Windows File Share on Windows 10 from Linux Mint 19 has yet another problem. But there is a fix. My Post Here drew the attention of someone who had the answer.

The problem is that trying to reach a Windows 10 shared folder from a Linux Mint 19, or Ubuntu 20.04, system, causes an error:

“Failed to retrieve share list from server”

Here’s the workaround.

Samba woes SOLVED Linux Mint Forums.png
The Workaround

It’s pretty easy. And you can do two things.

  1. When it asks for “credentials” mark them “remember forever” and store them in your keyring, so you never have to worry again.
  2. And use “Bookmark” in the file browser to remember the share so you can easily go back there again the next time you need the Windows Share from Linux.

I was able to use the smb://win10-host-name.local/share-name fix.

The bug has been reported here, so we are probably going to get a fix soon.

Update: 30 April 2020

I tried file sharing to Windows from Fedora 32, the latest, and it failed in the same way, and was fixed in the same way. So all the Linux distros apparently share the same samba gvfs code.

May you walk in the light of the Crystal.
:ww

Printing from LinuxVM

How to Share Printers on a Network.png
From 2017 – A long time ago

For a while now I’ve been wondering how to print from Linux running in a VirtualBox virtual machine to my local Windows Printer. Well it just works. Sort of.

I did what it says on this page and it did work. I thought I had tried this a while ago and never got it going. But there has been progress with Ubuntu / Linux Mint over the years and it looks like it works now.

Continue reading “Printing from LinuxVM”

ImpressShowRunner Released

ImpressShowRunner is running well on both Windows 10 and Linux Mint 19.

Go here to get the Jar file.

Here is a complete description of the program and how to use it.

The program is distributed as a JAR file and requires Java SE 11 or later to run. OpenJDK 11 is built in to Linux Mint 19 and the normal windows SE release is currently Java 8.  This will not work to run the program since it was developed for the JDK 11 version of Java. Actually. Let me get back to you on that. I have JDK 14 installed on the system I use to test on Windows 10. I need to sort out these Java version numbers and confirm that the program works on Java 8. Are Java JDK versions different from the RunTime environment versions? Let’s see.

Continue reading “ImpressShowRunner Released”

Java – We have the Technology

ShowRunnerOnLinux_2020-04-20 13-36-24
Java App running on Linux

We recently proved that Java desktop programs can be easily deployed to Windows and Linux. Now we have proved that other complex parts of the program to run a series of Impress Shows in a loop.

  1. Running the command line to launch the Impress program to show the slide show.
  2. Finding out when the show is complete.
  3. Clicking the mouse repeatedly so that the show ends when it finally reaches the black screen.

1 and 2 are pretty easy. In Qt there is a class that executes a command in another process. And you can wait on it or check to see if it is complete. We can’t wait of course since Impress just waits forever for a click on a black screen at the end. Soooo.

3 is not so easy on Qt. The solution differs by OS. On windows you need to call the Kernel to send events to be dispatched through the event handler. UINPUT calls. On Linux, the easiest solution I found was to launch the “xtodo click 1” command to perform a mouse click. The xtodo command is easily installed on Linux, but this is another step to make the program work. But the Java solution is much easier.

Continue reading “Java – We have the Technology”

Java Deployment Is Easy

ShowRunnerOnLinux_2020-04-20 13-36-24.png
Show Runner on Linux

I’ve been using QtCreator and the QtFramework for many years to build apps for Windows / Linux. Deployment is always a struggle with the Qt Framework. Deployment is hard work. Lots of hand work and testing to make sure the installers are correct.

I’m now forever done with Qt for that. Java is sooooooo much easier to deploy.

The above shot is of the prototype Java Impress Show Runner app running on Linux from a JAR file built on Windows 10. It runs on Windows 10 and it runs on Linux, with no changes and instantly. No fiddling required.

Here’s what it takes to build apps this way. Just an overview, not the entire story, but it has only been Five days since I started with Eclipse and Java. So it’s not that big an effort.

Continue reading “Java Deployment Is Easy”

Impress Show Runner Trivial on Linux

Update 11 April 2020: Using the xdotool method, the QtShowRunner works well on Linux, so there is a portable version for Windows and Linux. Get the latest at the github repo. I’m still investigating “Deployment” for Windows and Linux. Now, previously…

I have beat my head against the wall trying to fix the QtShowRunner program that works on Windows to work on Linux. None of the methods have worked.

  • Kernel uinput API calls never worked.
  • Using the X11 XSendEvent to send either Mouse clicks or Key events didn’t work.

Finally I found a command called xdotool which does many X things including sending mouse clicks and key presses. Here’s a shell script that uses the xdotool to launch soffice impress to show a slideshow and then terminates the show and then exits the script.

Screenshot from 2020-04-09 20-11-31.png

The script launches the show with the ending & to detach it. Then loops looking for the process using pgrep and if it’s still around, uses xdotool to click the mouse and waits for  5 seconds. When the process finishes the show, and the click ends the show, then pgrep fails and the script exits. Trivial.

Continue reading “Impress Show Runner Trivial on Linux”

Gigabyte Brix 7200 Displays 4K

I’ve had a Gigabyte Brix GB-BKi5HA-7200 for a while now.

20181217_071122.jpg

This is about the 3rd Mini system that I’ve had. Maybe fourth if you include one that I built from parts. This one has:

Linux Mint Fails in 4K

It was running Linux Mint 18 and recently Linux Mint 19. And this was working fine, except recently I upgraded the monitor to a Samsung 40″ 4K TV – UN40MU6300FXZA. I found the Refurbished TV for about $290 for sale by Walmart a couple of months ago. This is quite a good price for this Samsung 6300 level TV.

Walmart_- Samsung 4K UHD TV_-_2018-08-04_15.37.31xx.png

Since I use this mini system to display photos and game screen shots a large high-rez display is just the thing. However, Linux Mint has never supported the display correctly.

As you can see, when in 4K [3840×2160], the display is sliced up and repeated across the screen. It works fine in 1920×1080 mode on Linux. From all the reading of the processor and TV specs, it looked like it should work fine and when I use a long HDMI cable to plug the TV into a Windows 10 system with a GTX 1060 card, it works fine too in 4K.

I am using a pair of 2K monitors through a IOGear Displayport switch and Linux Mint works just fine with that using a GTX 1050 card, which has DisplayPort output.

After spending a couple of days on various forums trying to understand and fix the problem on the BRIX with no luck, I had the bright idea of just trying Windows 10 directly on the system. So I made a Windows 10 install Thumb drive, removed the M.2 Sata, to avoid messing up the Linux Install with Windows 10, and installed Windows 10 on the 60GB SATA SSD. Worked like a charm and brought the monitor right up in 4K without problems.

Continue reading “Gigabyte Brix 7200 Displays 4K”