Other B4J v4.50 BETA is available for download


B4X founder
Staff member
Licensed User
Longtime User

New features and improvements:

  • Many improvements to the IDE docking framework, especially with floating documents that now behave like regular windows.
  • New themes.
  • Support for bookmarks:


  • URLs in comments or strings are clickable.
  • jControlsFX library was updated to latest version of ControlsFX.
  • Gzip compression for server responses (Server.GzipEnabled).
  • DosFilter - A filter that helps with protection against denial of service attacks.
    srvr.AddDoSFilter("/*", Null)
    See this link for more information: http://www.eclipse.org/jetty/documentation/9.4.x/dos-filter.html

  • RadioButtons added with the designer are grouped automatically based on their parent.
  • Bug fixes and other minor improvements.

Download link: www.b4x.com/b4j/files/beta.exe
Last edited:


Active Member
Licensed User
Longtime User
i use the same project on many PCs (20+PCs) as a portable b4j , if i used this beta now on one PC , will i have to install it on all other devices , or is it backwards compatible? i.e : other devices with 4.20 version will be able to run the same project normally , or do i have to install this beta on all the other devices ?
Upvote 0


Licensed User
Longtime User
1. Make sure that you have a folder named c:\temp.

I ALWAYS use a force directory or create directory (in my codes) to ensure this folder exists rather than relying on it pre-existing...
Upvote 0