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  • Screens from Chalkboard Electronics - both their older 10" 800x600 screen (2012 model) and their 10" 1280x800 screen (from the beginning of 2013)
  • The M2256PW monitor from 3M
  • The touch screen integrated into the Freescale i.MX6Q Sabre Device Platform.

In general a touch screen that is recognized by Linux and generates EV_ABS events will work with JavaFX.

Raspberry Pi OS

Tested:

  • Raspbian Jessie

  • Raspbian Jessie Lite

    • Note: is missing the Pango package for running OpenJFX. Easily fixed with "apt-get install libpango-1.0-0:armhf libpangoft2-1.0-0:armhf"
  • NOOBS (v1_4_1) installing:

    • Raspbian Debian Wheezy (2015-05-05)

When the raspi_config options are displayed, there is one critical item for OpenJFX. Under "Advanced Option" choose "Memory Split" and set the value to 128 or 256. This is the memory allocated for GPU use. OpenJFX can use quite a bit of memory for textures and shaders. The amount available to OpenJFX cannot be queried from the OS, and OpenJFX cannot always handle the failure gracefully. You can always run the raspi_config tool after install to change the value.

The Jessie images were tested with jdk-8u65-linux-arm32-vfp-hflt.tar.gz, which is downloadable from the Oracle JDK8 download page. Note that this version of the JDK does not come with an integrated JavaFX. JavaFX can be obtained by building OpenJFX for ARM, or by using one of the community builds.

OLDER DISTRO NOTES

The configuration used by Oracle for testing is:

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  • Make sure to expand the filesystem, or you won't have enough room to install the JDK.
  • If you are using the device primarily with JavaFX, you will probably not want to select "Enable Boot to Desktop". JavaFX on the Pi takes over the whole screen and does not interact with the Linux desktop.
  • Under "Advanced Options" you can select "Memory Split" to allocate memory to the graphics processor. A 50/50 split will let you get most use out of JavaFX accelerated graphics.
  • If you are using JavaFX over ethernet, it can be convenient to turn on the SSH server under "Advanced Options". Since JavaFX takes over input devices, it can be hard to stop an application if you don't have an SSH connection to it from another machine.

Because of the way JavaFX is run, it is sensitive to the system screen blank timer. To disable the screen blank timer, edit the file /etc/kbd/config and change the lines for BLANK_TIME and POWERDOWN_TIME to be 0 (disable), and reboot. If not disabled, many applications will appear to stop after 30 minutes or so of use.

 

Tip

If you are connecting to your Pi over the network, you can save some time by setting a host name, and enabling ssh access for it in raspi-config, then installing the avahi-daemon package (sudo apt-get install avahi-daemon from the command line). You'll then be able to reach the Pi from a Linux PC with the command: ssh pi@<host name>.local

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Then open /boot/cmdline.txt in an editor and add on the same line as the other options dwc_otg.speed=1. Run sudo sync and reboot. This drops USB speeds from 480Mbits/s to 12Mbits/s, which is known to resolve issues with a variety of USB devices on the Raspberry Pi.

Running a JDK

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Raspbian has Java SE 7 preinstalled on the image. This version does not contain JavaFX. To obtain JavaFX download either:

This downloaded You can get a early access build for ARM hard float from http://jdk8.java.net/download.html. This bundle should be unpacked on the Pi. For example,

Code Block
themeMidnight
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sudo tar zxvf jdk-8-ea-b97-linux-arm-vfp-hflt-03_jul_2013.tar.gz -C /opt

To check that the JDK is installed correctly, run:

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This should show that you are running an EA build of JDK 8. If the VM won't even start, you might be running a hard-float VM on a soft-float system.

To avoid confusion, change your PATH variable so that the newer version is earlier in the path.

You can use the samples bundle from https://jdk8.java.net/download.html on the Raspberry Pi. Not all the samples will work on the Pi; here are some that will:

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Warning

The JAVAFX_DEBUG environment variable is only for use in development and you shouldn't rely on it for deployment of your application. In the future this functionality might be specified differently or be removed.

Raspberry Pi Memory Split

The older versions Raspberry Pi Raspian preallocate a fixed amount of the system memory for use by the video engine (VRAM).  The utility raspi_config can be used to alter how much memory is allocated to VRAM.

Newer versions of Raspian can dynamically allocate system memory for use as VRAM.

The minimum recommended memory split for JFX on the Pi is 128 MBytes, with many applications requiring 256 MBytes.

This JavaFX texture caching mechanism currently defaults to 512 MBytes - a value that will likely exceed what is available on the Pi. Given the limited amount of VRAM on the Pi, it is quite possible that an image intensive application might fail when the cache exceeds the available system limit.

Read this page for more details on VRAM and tuning.

Touch events

A touch screen attached to the Raspberry Pi generates both TouchEvents and MouseEvents. Only a single touch point is supported by default, but there is experimental support for multitouch events. To enable multitouch, set the system property -Dcom.sun.javafx.experimental.embedded.multiTouch=true on the Java command lineThe Monocle subsystem in the latest OpenJFX sources supports a wider range of touch screens than the 8u6 release does and also supports calibration.