For Users:

Current version is 0.14.2 for Minecraft 1.2.5

For Modders:

GuiAPI is now fully documented, has MCP source files, and includes a few examples.

You can view the source code on my Github, at

Javadocs are currently located on my Dropbox, at Javadoc/index.html.

If you wish to code with GuiAPI, the easiest way is with MCP. Note that since GuiAPI uses generics, and most decompilers can’t handle those well, it will not decompile cleanly. Currently, the best way is the following.

Copy the Developer Package into your minecraft.jar. This can be before or after you decompile, as it’s just the files needed for GuiAPI to run (TWL and other libraries for it, as well as the theme and font), and as such none of it is decompiled by MCP.

After that, grab a copy of the source from Github. I have tagged the releases for you, so visit and click the one you need. Inside that zip file, go to the folder named mcp. It shouldn’t be hard to find.

Now, these files are GuiAPI’s source code. Just copy all of these files into MCP’s src\minecraft\net\minecraft\src folder. This will overwrite If you have made any changes to that file, you can either do those over again OR you can view the information on Github for patching in GuiAPI’s changes.

After this, just compile and you should be all set.

If you have modified GuiAPI by updating the theme, adding a new Widget, added functionality, or fixed a bug, please by all means contact me with details below or open a new issue on Github.

How to Install GUI API for Minecraft 1.2.5

  1. Download the GUI API for Minecraft 1.2.5
  2. Drag all the contents from the extracted file into the minecraft.jar
  3. Delete META INF
  4. That should do I hope.

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