B4J Tutorials

Working with files

The File methods in B4J are identical to B4A File methods.

Text file methods

File.WriteString - Writes the given text to a new file.
File.ReadString - Reads a file and...
 
Last edited:
Click to expand...

Using Sliders

This is a simple example that shows :
Using sliders
Re-sizing windows
Changing background colour of a window
Truncating/Expanding text
Moving labels to keep pace with a slider button
Text with...
 

Attachments

  • SlidersAndText.zip
    2 KB · Views: 1,155
Click to expand...

jexcell and other librairies

How do I install the jexcell bookstore?
In fact I can not find it on the site.
 
Click to expand...

[WebApp] Example Task Manager using WebSockets & SQLite

This example is a simple Task Manager using HTML to access the server by the Client.
The tasks are stored in a SQLite database, which is managed by the B4J WebServer.
Read...
 
Click to expand...

[WebApp] (mini) Template Engine

WebUtils.ReplaceMap together with the CreateMap keyword are useful for building dynamic strings, especially for html output.

For example, in the chat example when a user writes a message we...
 
Click to expand...

[Server] Performance measures

B4J server library is based on an open source project named Jetty.
Jetty server performance is excellent which means that B4J server performance is also excellent.

The following numbers are the...
 
Click to expand...

What is B4J?

Last edited:
Click to expand...

[WebApp] Custom Elements - DatePicker & Dialogs

The web app framework can be easily extended with new elements and new features.

In this example we use two elements from jQuery UI library...
 

Attachments

  • DatePicker.zip
    3.6 KB · Views: 1,560
Click to expand...

GuessMyNumber - Very simple example



The computer chooses a number and you need to find the correct number.
B4X: 
Sub Process_Globals
   Private fx As JFX...
 

Attachments

  • GuessMyNumber.zip
    1.3 KB · Views: 1,210
Click to expand...

String to variable - Iterate variable names

This is a simple idea to replace the function "eval" or "execute" that other programming languages have. The purpose is to retrieve a variable from a string:

How to iterate variable...
 
Click to expand...

B4J Change Log (version history)

Last edited:
Click to expand...

Working with JavaFX Scene Builder

This is an old and irrelevant tutorial.
 
Last edited:
Click to expand...

Parsing huge text files

The JVM (Java Virtual Machine) performance is quite amazing.

This means that we can use B4J to build apps that handle huge files.
I downloaded a 3.7GB log file from this server. Each line...
 
Click to expand...

Modules Attributes

The following module attributes are supported:

Main Module
  • MainFormWidth / MainFormHeight - Set the main form initial width and height.
  • AdditionalJar - An...
 
Last edited:
Click to expand...

Magnifying glass example



A Canvas node is used to magnify a small window under the mouse cursor.

The main code is:
B4X: 
Sub iv_MouseMoved...
 

Attachments

  • MagnifyingGlass.zip
    99.5 KB · Views: 1,168
Last edited:
Click to expand...

RDC client

Attachments

  • RDC-Client.zip
    3.4 KB · Views: 1,799
Click to expand...

Moving Smiley Example



This example uses a Canvas node together with a Timer to draw a moving smiley.

The Canvas node is a special node the you...
 

Attachments

  • Smiley.zip
    3.7 KB · Views: 1,979
Click to expand...
You must log in or register to post here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…