inspired from http://kio4.com/appinventor/125B_extensiones_crear_i.htm
download java https://www.oracle.com/java/technologies/javase-jdk8-downloads.html
download apache http://ant.apache.org/bindownload.cgi
download git https://git-scm.com/download
download appinventor kit from here https://github.com/mit-cml/appinventor-sources
install java and git ... unzip apache and appinventor
set manually windows variable or create batch script :
SETLOCAL
SETX _JAVA_OPTIONS "-Xmx1024m"
SETX ANT_HOME "E:\AppInventorExtensiones\apache-ant-1.10.8-bin"
SETX ANT_OPTS "-Xmx256M"
SETX JAVA_HOME "C:\Program Files\Java\jdk1.8.0_131"
SETX CLASSPATH "%ANT_HOME%\lib;%JAVA_HOME%\lib"
SETX PATH ";%ANT_HOME%\bin;%JAVA_HOME%\bin"
pause 0
Modify E:\AppInventorExtensiones\apache-ant-1.10.8-bin and C:\Program Files\Java\jdk1.8.0_131 with correct path
run this batch file 2-3 times ... because i see that if is executed one time thre variables is not set corectly
Now verify if all is ok:
open folder appinventor , click mouse right and select "Git bash here"
write "ant extensions"
if a final received "BUILD SUCCESSFUL" mean that all is ok !!!
What mean this? mean that have compiled none file ... because in folder
..\appinventor\components\src\com\google\appinventor\components\runtime is not added any new file
Now put Costy.java in this folder and write again "ant extensions" ... and after building will see this
and in appinventor\components\build\extensions will find
Download extension on http://ai2.appinventor.mit.edu/
and ... Congratulations ... you have make first extension that do ... nothing!