B4J Tutorials

[PyBridge] Communicating with Raspberry Pi

• By Erel
• Mar 12, 2025

This sophisticated project does one thing - the user clicks on a hardware button, connected to the RPi, and a notification appears on the PC.



The setup:
RPi running Mosquitto broker...

 

Last edited: Mar 12, 2025

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Make a simple 3D game with WebGL library, with gravity and collisions in less than 300 lines of code.

• By max123
• Mar 11, 2025

Hi all,

this code will show how to make a simple 3D game, with gravity and collisions by code without use any physics engine.

I want to remember that with WebGL library you can use more than one...

 

Attachments

• jWebGL_SimpleGame.zip

  292.8 KB · Views: 246
• Screenshot 2025-03-11 150808.jpg

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Last edited: Apr 19, 2025

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SithasoDaisy TailwindCSS UI Toolkit: Q & A

• By Mashiane
• Nov 19, 2022

Hi there

NB: Where possible, please include a simple project that demonstrates your use case.

Do you have any questions about SithasoDaisy UI Toolkit?

You can shoot it here...

 

Last edited: Jun 27, 2023

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Raspberry Pi 5 - first steps

• By Erel
• Mar 10, 2025

Getting the RPi 5 to work with B4J is very simple.

I've tested it with the recommended 64 bit Raspbian OS (bookworm).

1. Download and unpack the Linux ARM Full JDK (21)...

 

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Shrinking that SQLite JDBC library!

• By tchart
• Aug 4, 2020

NOTE: This isnt recommened for everyone, this is just something that works for me. Removing support for specific platforms could cause your app to stop working.

I use SQLite for a lot of...

 

Last edited: Aug 4, 2020

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[B4X] [PyBridge] Desktop - Mobile Communication based on BLE (Bluetooth Low Energy)

• By Erel
• Mar 9, 2025

I've posted in the past a few examples of a simple chat app based on BLE: https://www.b4x.com/android/forum/threads/ble-chat-connecting-android-and-ios.66543/#content
A new version of this...

 

Attachments

• B4XPeripheral.zip

  181.1 KB · Views: 225
• B4JCentral.zip

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Deutsche Post Internetmarke - get Stamps per Api

• By DonManfred
• Mar 8, 2025

This Thread is about the german Post and their free Api Service for Postalstamps and other Services...

 

Last edited: Mar 8, 2025

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[Web][SithasoDaisy5] Designing Web Forms with SDUIPreferences - Part 1

• By Mashiane
• Mar 7, 2025

Hi Fam

SithasoDaisy5 Demo incl Preferences Dialog Forms Builder

SithasoDaisy5 Open Source

Before you start this tutorial, please ensure that your dev environment is setup by...

 

Last edited: Apr 27, 2025

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Integrated B4JPackager11 - The simple way to distribute standalone UI apps

• By Erel
• May 17, 2020

B4JPackager11 is a utility written in B4J that uses the underlying Java tools to create a standalone package that doesn't depend on any other software being installed.
It works with OpenJDK 11 and...

 

Attachments

• jssc.zip

  69.6 KB · Views: 333

Last edited: Sep 16, 2025

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Cache for WebApp was keeping previous version of .js file - How to fix

• By hatzisn
• Mar 4, 2025

This was the first time I faced something like this and it was Chrome's fault. Here is what happened:

I added in a .js file a new javascript function. When I tried to call it, Chrome was saying...

 

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[Web][SithasoDaisy5] Designing Forms with the Abstract Designer

• By Mashiane
• Mar 4, 2025

Hi Fam

SithasoDaisy5 Demo

Before you start this tutorial, please ensure that your dev environment is setup by following this tutorial...

 

Last edited: Apr 27, 2025

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FXThemes

• By stevel05
• Feb 27, 2025

Now I have a windows 11 PC and thanks to a prod from one of @Cableguy posts on another thread, I finally got round to looking at an alternative to my Replacement Titlebar lib.

This...

 

Last edited: Feb 27, 2025

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jBluetooth under Linux: also works

• By peacemaker
• Feb 24, 2025

But if to make lots of preparations:
0. Do not forget to include into the B4J library folder file: www.b4x.com/b4j/files/bluecove-2.1.1-SNAPSHOT.jar

1. Install Linux Bluetooth Bluecove...

 

Last edited: Feb 26, 2025

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Creating Linux DEB-package for GUI B4J app

• By peacemaker
• Feb 20, 2025

This tutorial is made for Linux JDK14 set Java + JavaFX for B4J practically, AI suggestions were partially OK only.
The .jar app file is compiled at Windows developer host.

Building a DEB...

Click to expand...

 

Attachments

• TempDownload.png

  10.5 KB · Views: 199

Last edited: Feb 23, 2025

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B4J-Bridge dockerimage

• By Blueforcer
• Dec 18, 2018

A friend of mine created a docker image for me to debug apps on my server quickly and easily.
I am happy to share this with you.

https://hub.docker.com/r/o0shojo0o/b4jbridge

 

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[PyBridge] Linear regression with scikit learn

• By Erel
• Feb 17, 2025

This example is based on: https://scikit-learn.org/stable/auto_examples/linear_model/plot_ols.html
The steps are:

1. Read the CSV file with StringUtils.
2. Take the BMI and target columns...

 

Attachments

• Project.zip

  27 KB · Views: 208

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[PyBridge] Tips to make life easier

• By Daestrum
• Feb 17, 2025

1, Download VSCode to edit the Python source files (you get hints etc)
2, Put the Python source code in files directory. (set external tool to VSCode for easy editing)
3, Run the code from...

 

Last edited: Feb 17, 2025

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MathArt

• By Johan Schoeman
• Feb 2, 2025

Sure you will figure it out. Four rotating/pivoting arms of different length and rotating at different speeds (some CW and some CCW) to make all kinds of interesting drawings. Change the speed /...

 

Attachments

• b4jMathArt.zip

  2.9 KB · Views: 253

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HTMX+Bootstrap5+MiniHTML+WebApiUtils+Server

• By aeric
• Jan 25, 2025

This example uses B4X,

• specifically MiniHTML library
• cross over HTMX to generate interactive HTML
• based on Modal Dialogs in Bootstrap example on HTMX website
• to...

 

Attachments

• WebApiUtils.b4xlib

  8.9 KB · Views: 229
• MiniHtml.b4xlib

  19.8 KB · Views: 223
• htmx-b4x.zip

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Last edited: Jan 27, 2025

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Tip : B4XLib documentation

• By walt61
• Jan 26, 2025

I recently spent half a day on a wild goose chase trying to find out what was going on with SQLCipher, while the issue turned out to be B4XTable.b4xlib containing an #AdditionalJar for...

 

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