JRE 8 or later
JDK 8 or later
Maven
lol-client-java-api
Using Git Bash
git clone https://github.com/stirante/RuneChanger.git
cd RuneChanger
mvn package
Just run jar or start it using java -jar RuneChanger.jar
for extra logging
RuneChanger uses internal LoL client API. If it finds active session it gets rune pages for currently selected champion and displays option to set those runes to active rune page.
The button is actually completely separate window which tracks client position and size to be exactly where it should be.